Future of Device IO: APL Single Pair Ethernet

New fast silicon networking chips will enable Single Pair Ethernet (SPE) networking in future field instrumentation known as the Advanced Physical Layer (APL). APL is a network technology for field instruments to the control system based on fully digital networking instead of point-to-point hardwiring 4-20 mA and on-off signals. Products are not available yet, but it will transform both instrumentation and control systems. New digital technology inspires ideas and sparks our imagination of new kinds of products working together in never seen before ways; ideal for Industrie 4.0 and digital transformation (DX) in digital plants with many more sensors, and actuators, and many more real-time signals each. Let’s review the benefits of real-time digital I/O signals and the vision of new exciting field instrumentation. Here are my personal thoughts:

Limitations and Challenges of 4-20 mA and On-Off Signals

Point-to-point hardwired 4-20 mA, on-off, and pulse signals have been in use since the sixties and are the principal way in which field instruments are connected in most plants until today. Considering the long lifecycle of automation systems, 4-20 mA and on-off devices will remain in plants for a long while. However, 4-20 mA and on-off signals have many limitations. They are not broken; plants still work so we continue to use them, but the limitations prevent plants from being better. We don't think much about the measurement errors, occasional false alarm, additional work, impaired visibility, or that devices have limited functionality - because it has been that way for a long time. A bit like the traditional telephone system. Anyway, these limitations are the reasons why process production companies are now looking for a new digital solution for future plants to be better than the plants we have today.

Hardwired Operations Limitations

The limitations of 4-20 mA and on-off signals may stand in the way of the plant achieving its operational excellence goals of higher product quality and throughput, greater availability, and reduced human error. The hardwired limitations affecting operations are:

Hardwired Maintenance Limitations

The limitations of 4-20 mA and on-off signals may stand in the way of the plant achieving other operational excellence objectives like lower maintenance cost, shorter turnarounds, and reduced downtime. The hardwired limitations affecting maintenance are:

Hardwired Project Challenges

The limitations of 4-20 mA and on-off signals have an impact on the greenfield project such as engineering time and cost, hardware and installation cost and time, commissioning time and cost, as well as large control system footprint and weight. The hardwired limitations affecting the project are:

Digital Technology is Transformational

A seminal Harvard Business Review (HBR) November 2014 article “Digital Ubiquity: How Connections, Sensors, and Data Are Revolutionizing Business” highlights fundamental properties of digital technology that makes it transformational:

Image courtesy Harvard Business Review / Harvard Business School

The first four points open infinite possibilities which is the reason why everything around us is changing from analog signals (like 4-20 mA) to digital. The fifth point is why interoperability testing is important and standards around the APL technology are being created.

Digital networking overcomes the limitations of 4-20 mA and on-off signals. It thus enables better plants. Better control, greater measurement accuracy and integrity, reduced work, greater situational awareness, and new innovative devices. A bit like modern phones. These capabilities are what the process production companies like NAMUR members are looking for, so their next plant will be better than the ones they have today.

Digital Operations Benefits

Operations benefits resulting from real-time digital input/output (I/O) signals include higher quality and throughput, greater availability, and reduced human error. The digital capabilities benefitting operations are:

Digital Maintenance Benefits

Maintenance benefits resulting from real-time digital I/O signals include better maintenance and turnaround planning, easier daily maintenance, and greater availability. Not just improved I&C maintenance, but also improved maintenance for rotating machinery like pumps and static equipment like heat exchangers thanks to additional sensors. The digital capabilities benefitting maintenance are:

Digital Project Benefits

Offsite (design office) and onsite project benefits of real-time digital I/O signals include lower hardware and installation cost, reduced control system footprint and weight, reduced engineering time and cost, as well as reduced commissioning time and cost. The digital capabilities benefitting projects are:

Regular Ethernet in I&C

Regular Ethernet along with TCP/UDP/IP are well established in process automation, used for workstations, servers, DCS controllers and PLCs, as well as I/O-subsystems, motor drives, and starters since more than 20 years. That is, Ethernet has been very successful for indoor computers and devices in cabinets. However, Ethernet did not see much success at the field-level. Regular Ethernet including Power over Ethernet (PoE) are not suitable for process instrumentation in large plants. Also, regular Ethernet is overkill for most field instruments like pressure and temperature transmitters, and it is hard to justify running Ethernet into the field just for a few flow meters. Therefore most field instruments have until now been using 4-20 mA and on-off signals.

Moreover, regular Ethernet is not intrinsically safe so other protection methods have to be used in hazardous areas, such as explosionproof/flameproof. Ethernet cable has 4-pairs of wires (although only 2 of the pairs are used for communication) so special attention must be paid when crimping the connectors to ensure pairs are not crossed and all wires are connected. A special crimping tool is required for the standard RJ45 connector. Although PoE is a possibility (using the other 2 pairs of wires in the Ethernet cable), most Ethernet device require separate power cabling which is costly. Lastly, copper Ethernet is limited to 100 m which is far too short for use in plants. Although fiberoptic cable can be used for longer distances, the tools and skills required make it unpractical for the large number of devices in a plant.

Single Pair Ethernet (SPE): Advanced Physical Layer (APL)

The future Advanced Physical Layer (APL) technology or “Ethernet-APL” will use Single Pair Ethernet 10BASE-T1L for industrial environments, a standard just recently completed called IEEE 802.3cg. It will be fully digital real-time network, no 4-20 mA. Ethernet for the field level. Ethernet will be homogenous from field instruments to boardroom. Field devices like pressure, temperature, level, and flow transmitters, analyzers, plus control valves, as well as discrete devices like level switches and on-off valves will use APL networking; a two-wire cable (i.e. a single twisted-pair cable instead of four-pair cable for regular Ethernet) and you will be able to lay the length required of cable, pushing through cable glands (without patch cords or connector assembly). This also means devices will be connected using two rugged screw terminals or cage clamp (as opposed to the flimsy RJ45). It will support a 1,000 m trunk (as opposed to only 100 m for regular Ethernet) from controller cabinet to the field junction box, and 200 m spurs (also only 100 m for regular Ethernet) from the field junction box to the devices. It will be intrinsically safe two-wire power (as opposed to regular Ethernet which isn’t). It will run at 10 Mbit/s; almost ten thousand times faster than HART and three hundred times faster than conventional fieldbus. You will be able to run multiple control loops per network, including complex loops, at 250 ms or faster. More and faster than with conventional fieldbus. Configuration download and commissioning will be faster. It will be using shielded twisted-pair cable in balanced mode and will be compatible with UDP/TCP/IP and all Ethernet application protocols including industrial application protocols and general-purpose protocols for web browsing. There will be a whole range of companies making APL root switches, field switches, power supplies, laptop interfaces, and repeaters etc.

Do not confuse APL technology with Power over Ethernet (PoE), they are not the same.

It is expected APL technology will not have as frequent enhancements as regular Ethernet and that backwards compatibility will be ensured

APL Cable

APL networks will use #18 AWG shielded twisted pair cable. Power and communications coexist on the same two wires. That is, the type of cable is different from regular Ethernet cable. Indeed it is the same type of cable used by common fieldbus like PROFIBUS-PA and FOUNDATION fieldbus H1.

Image by Phil Frank and Joe Troise in Network World magazine

Grounding must be done as per local regulations. Various types of grounding schemes will be supported to make it possible to meet local regulations.

Special connectors will not be required. Most devices will use regular screw terminals or clamp. This will make APL networks more rugged than regular Ethernet. Nevertheless there will for sure be special connectors and molded cord-sets offered by some vendors as well for those that prefer that.

APL cables will have to be laid together with other signal cables such as Ethernet, fieldbus, and 4-20 but away from power cables.

APL Field Switch

The trunk from the control system will land on the APL field switch located in the field junction box. From the APL field switch spurs will branch out to the individual APL field instruments. No separate terminators will be required as they will be built in. Since the APL field switch will be powered from the APL network itself, no separate power supply wiring will have to be run into the field. This will make APL networks more cost effective than regular Ethernet. That is, the trunk is like the multicore homerun cable in hardwired installation but using single pair. The spur is like the single pairs from the field junction box to transmitters, switches, valves, and solenoids - but one pair will handle all the signals for the APL device.

200 m spur means it will be possible to connect the devices within a radius of 200 m to a field junction box. A plant unit will have multiple field junction boxes to cover devices which are further apart, just like for hardwired but with less wires.

Note that an APL field switch will not have fans or other moving parts. They will work within an industrial temperature range and be encapsulated to handle humidity etc. such that they can sit outdoor in a regular field junction box without climate control.

It doesn’t matter which device connects to which port/spur of the APL field switch as the data will automatically finds its way to the destination based on tag and address.

Vendors have already demonstrated rugged and intrinsically safe APL field switches with 12 spurs (i.e. 12 ports for 12 devices), but the APL technology enables more, so in the future we may see more devices per network if the industry demands it. However, note that on average APL devices will probably have about 3 I/O each; meaning one APL field switch really handles the equivalent of about 36 I/O signals. Based on the size of the demonstrated APL field switches, it is expected these field junction boxes will be small and lightweight (350 x 460 x 170 mm, 8 kg). If there are more than 12 devices in the vicinity of the field junction box, more than one APL field switch can be installed in a larger enclosure. If the APL field switch will only be populated with 10 out of 12 devices, that automatically means 20% spare capacity.

It will be possible to use multi-pair trunk cable from the control cabinet for the main distance to a main junction box in the field, from where single trunks can branch out to individual field junction boxes. No special terminal blocks or switches will be required in the main junction box.

It will be possible to add devices, even multiple at the same time, to a running network and configure them without disturbing existing devices.

It will be possible to use APL networking and devices in general purpose or hazardous areas. There will be various methods of explosion protection for hazardous areas to choose from. The existing rules for hazardous areas apply to APL networks and devices as well, just like for hardwired signals. Flameproof (explosionproof), intrinsic safety, and others will be possible. For intrinsic safety, an intrinsically safe certified field switch will also serve as the safety barrier. The APL trunk will use increased safety (Ex e) protection method. The spurs will be intrinsically safe (Ex ia). It will be possible to install the APL power supply in zone 2 (class I, division 2), the APL field switch in zone 1 (class I, division 2), and to have field instrument in zone 0 (class I, division 1). To make intrinsic safety engineering easy for APL networks, a “2-Wire Intrinsically Safe Ethernet” (2-WISE) specification for standard Exi entity parameters similar to FISCO is being developed.

APL networks will be different from conventional fieldbus. The implementation of the APL field switch is the main difference in that it really creates a hub and spoke topology just like modern Ethernet. Each spur has a repeater like a 10Base-T Ethernet hub such that each spur will be its own segment and every device will really be connected point-to-point to the field switch. This means APL networks will be easy to engineer as there will be no need to sum up the lengths of spurs and trunk. Just make sure trunk is 1,000 m or less and each spur 200 m or less (i.e. devices within 200 m of the FJB).

The repeater function in the APL field switch will also provide signal integrity checking just like Ethernet switches. This means noise on one spur will not be propagated to the rest of the network. Noise would only affect a single device, like for point-to-point hardwiring wiring. This will make APL networks more robust and easier to troubleshoot than conventional fieldbus as you will be able to see exactly which spur has a problem. You will be able to put multiple control loops on the same network.

APL Root Switch

In the control system cabinet there will be an APL root switch (sometimes called power switch or Ethernet switch). The APL root switch will essentially act as a media converter from APL media to regular Ethernet media. No application protocol conversion required (so it is not a gateway). Power for the devices on the APL network will also be supplied from this end of the network. Various implementations of APL interfaces in control systems can be expected from control system vendors and infrastructure component vendors:

• Built-in power supply or separate power supply
• Different numbers of ports
• Redundancy
• Embedded control capability (function blocks)
• Native DCS integration and management

Key will be to run APL networking and Ethernet with UDP/TCP/IP and application protocols unbroken all the way from the field instrument to the controller and software without going through any intermediate proprietary backplane, network media, or application protocols.

APL root switch and APL power supply will normally be installed indoor for easy access. The APL cable will come from the field junction box and land directly on the APL root switch in the control cabinet. There will be no marshalling cabinet

The APL root switch will connect the APL network direct to Ethernet at the IO-network (level 1) or control network (level 2). At a remote site the APL root switch may connect directly to a 3G/4G/5G router to the cloud.

Ethernet does not “flatten” the enterprise architecture, but there will be Ethernet at every level

From the APL root switch the network will connect to local copper Ethernet, fiberoptic Ethernet Wi-Fi, or in the case of remote applications to 3G/4G/5G mobile network, satellite, microwave data link, Internet, or even dial-up, all at various speeds as required.

The APL power supplies and root switches will be installed in general purpose area or Zone 2 (class I, div 2). From the APL root switch, data will branch out to the DCS controller for Core Process Control (CPC) and to the Digital Operational Infrastructure (DOI); a second layer of automation for monitoring and optimization (M+O) as per the NAMUR Open Architecture (NOA) for Digital Transformation (DX) with Industrie 4.0 (Industry 4.0). The second channel is the uninterrupted application protocols all the way from the field instruments, for instance for the Intelligent Device Management (IDM) software. The principal data channel from the DCS to the DOI will be OPC-UA for the M+O software. OPC-UA servers convert between the field device application protocols and OPC-UA. In the future some field instruments will include OPC-UA server for field level communication (FLC).

The APL root switch may come from the control system vendor or third-party infrastructure supplier. An APL root switch from the DCS vendor will likely have tighter integration with the DCS engineering station software for network management and diagnostics through vendor-specific functionality.

Vendors have already demonstrated APL root switches and APL field switches that have embedded webservers for network diagnostics and setup from a web browser on a computer, smartphone or tablet, locally or centrally. However, I personally believe it will be better to let the DCS automatically manage the switches. But sure, in a small installation without a DCS, manual management from a web browser will be very convenient. The web browser interface in read-only mode will likely also be helpful during commissioning and troubleshooting; without having to share the DCS engineering workstation. The webserver in these infrastructure components will have access control to prevent unauthorized changes. It is expected these switches will support the Simple Network Management Protocol (SNMP) just like other Ethernet infrastructure components. It will be possible to save the APL root switch and APL field switch configuration as a backup file, and restore if needed.

In the future, the APL root switch may have the capability to do some control and become the controller. Conversely, in remote applications the controller (RTU) may become the APL root switch.

The implementation of the APL technology will be different from conventional fieldbus in that there will probably not be any interface card in the control system backplane. Instead control data will go direct to the controller. Other data for asset management bypasses the controller go into analytics, possibly through an OPC-UA server without passing through the DCS controller. Engineers have a knack for figuring out what additional measurements they need to solve a problem; with digital networking they will have a simple way of adding these sensors.

APL Field Devices

APL field device like transmitters, control valves, on-off valves, and electric actuators / motor operated valves (MOV) will share the same network; a single infrastructure covering all field instruments. Device will likely be designed to support both intrinsic safety as well as flameproof/explosionproof. The APL network provides power to most of these field instruments. It will be possible to install APL field devices in general purpose area, zone 2 (class I, div 2), zone 1 (class I, div 1), or zone 0 (class I, div 1). Some very power-hungry field devices will still need separate power, but many devices which today are four-wire separately powered will in the future only need APL networking. Process switches such as level switches, pressure switches, and flow switches will either be made available in an APL version, or users will simply use corresponding entry-level transmitters instead which will provide additional benefits.

Motor starters, variable speed drives (VSD) / variable frequency drives (VFD), weighing scales, sheltered analyzers, power meters, etc. may use regular Ethernet as they are usually indoors with short distance. Ultimately the networks join together at a higher-level network, all devices part of the same automation system. Data from regular Ethernet and APL devices will be accessible to all apps.

There will be discrete APL devices such as on-off valve couplers and vibrating fork level switches etc. APL control valve positioners will have built-in position feedback not needing separate limit switches. Electric actuators / Motor operated Valves (MOV) will become available with APL positioner module. Entry-level pressure and flow transmitters will be used in place of pressure and flow switches. Nevertheless, for any remaining discrete IO signals vendors have already demonstrated remote-IO boxes with APL interface that will handle leftover hardwired I/O. Having said that, a native APL device with direct connection to the APL network without intermediate hardwiring would be preferred for simple installation and better diagnostics etc.

It will be possible to create a device configuration offline, for instance when building the control system database offsite before shipping to site, and then download into the device at device commissioning.

The APL technology is different from regular Ethernet. APL devices will have a terminal block with rugged screw connectors (or cage clamp) just like your hardwired field instruments do today. No flimsy RJ45 connector or regular AWG #24 Ethernet wires.

Industrial Application Protocols

Note that just “APL”, “SPE”, “10BASE-T1L”, “IEEE 802.3cg”, “Ethernet”, “UDP”, or “TCP/IP” doesn’t mean interoperability, it just means devices using different application protocols can share the same network. For two devices or software applications to interoperate; to communicate with each other, they must also use the same application protocol. There are several thousands of application protocols for IP and Ethernet. Most of them are proprietary application protocols. Most are not for industrial applications. Still, there are several open industrial Ethernet application protocols. Indeed, for every open standard fieldbus protocol there is an open standard industrial Ethernet application protocol.

For every fieldbus there is an Ethernet

There are big differences between these application protocols. The NAMUR NE168 recommendation “Requirements for a field level Ethernet communication system” lists some 91 requirements whereof 39 are basic APL/Ethernet/IP requirements and 52 are application protocol related requirements. The various application protocols meet these requirements to a greater or lesser extent.

The difference between APL technology and conventional fieldbuses is that on an APL networking you will be able to run FOUNDATION Fieldbus, Modbus, PROFI, CIP, and HART etc. application protocols over the same network so devices using different application protocols can share the same network infrastructure. However, it doesn’t mean that a Fieldbus device will talk to a PROFI device or a Modbus device to a HART device. You still must sort out the differences in application protocols. Therefore it still makes sense to as far as possible standardize your plant to a subset of these application protocols and attempt to buy most of the plant devices and software based on these. These application protocols already work across Ethernet, Wi-Fi, and fiber optics at a higher level above the APL root switch. The name “Modbus TCP/IP” is sometimes used but is not correct. It should be just “Modbus/TCP”

There is no “single Ethernet”

Since IP supports multiple application protocols in parallel, more than one application protocol can be supported in the same device, and automation system applications may use different application protocols for different functions. Many regular Ethernet devices already support multiple application protocols today. For instance, a PLC may be using EtherNet/IP or PROFINET-IO for real-time closed loop control data. The DCS may be using FF-HSE for real-time closed loop control data. Analytics software may be using OPC-UA. WirelessHART gateways, HART multiplexers, and remote-I/O boxes with pass-through to Intelligent Device Management (IDM) software may be using HART-IP. Modbus/TCP may be used for package unit integration. Many devices will also implement proprietary application protocols over UDP/TCP/IP for ‘special functions’, in parallel with the open application protocols, accessed through dedicated apps. APL field instruments will likely support multiple application protocols so various kinds of automation systems will be able to access them at the same time.

To ensure interoperability, only buy control systems, devices, and components conformance tested and registered by the corresponding independent protocol organization. It is expected that registered control systems, devices, and components will be listed on the corresponding organization’s website. Vendors will also be able to submit a copy of the registration certificate with tenders etc.

OPC-UA FLC

The OPC-UA technology is mostly used as a software-to-software Application Programming Interface (API) using a client-server interface, but may in the future increasingly be used for device-to-device (hardware-to-hardware) communication. This is referred to as OPC-UA Field Level Communication (FLC). However, for real-time communication OPC-UA shall be publisher-subscriber (PubSub) mode of communication, not regular client-server mode.

Proprietary application protocols

Note: just like for regular Ethernet, for APL networking it will even be possible for device vendors to implement proprietary application protocols in parallel with standard industrial Ethernet application protocols over TCP/IP, all the way down into the field instruments. If APL devices (or regular Ethernet devices) only support a proprietary application protocol there will be no interoperability. First and foremost, plants will want to make sure devices support at least one of the standard industrial Ethernet application protocol(s) chosen by the plant. Second, plants will want to check which functions (if any) use proprietary application protocols. Any functions using proprietary application protocols (e.g. special function setup, advanced diagnostics, or calibration etc.) will have interoperability challenges; at the time of initial project, or during future device replacement. The reason for this is because devices with proprietary application protocols do things differently from all other devices so special system integration engineering with special device driver program installation, data mapping configuration, and special software installation and maybe licensing is required. Device replacement will not be possible by an instrument technician. A system integrator will have to be called upon.

Beware of proprietary protocols over IP and Ethernet

APL Interoperability

Interoperability between field devices and control systems will be essential to make system integration easier. This requires a full-fledged application protocol with object-oriented information model with logically grouped information, standard data types, semantics like assigned numbers, and device description files etc. It will not be achieved with only a messaging protocol like MQTT, AMQP, or COAP. Messaging-level protocols require much more system integration engineering. Interoperability is technologically more demanding than the mere coexistence enabled by Ethernet, APL networking, and UDP/TCP/IP.

Modbus has no defined information model, data types, semantics, or device descriptor file so it requires a lot of manual mapping of data to registers. Therefore only a subset of information tends to get mapped meaning only a subset of device functionality becomes accessible. The advantage though, is that Modbus is supported in lots of software and lots of people know how to do it. Configuration and testing is time-consuming and error-prone, but eventually you can make it work.

APL Network Management

APL devices will have a MAC address and an IP address. Some plants will prefer a dynamic IP address assignment for devices set automatically by a standard Dynamic Host Configuration Protocol (DHCP) server on the network, while other plants will prefer static address set automatically by the DCS. Easiest for instrument technicians will be if the control system automatically assigns the IP address to the APL device. Some modern application protocols, but not all, support address annunciation to make it easy for the control system to automatically discover the IP address of a device to start communication for setup. Many Ethernet devices do not, so if the IP address is not known it can be tricky to get started and may require factory reset to get a known default address.

32-character tag is supported in most modern application protocols, but not all. The plant will be able to buy the APL device from factory with a preassigned a tag. Depending on the application protocol, when the device is connected to the network, the control system will detect the tag and will bind the IP address automatically to the device tag in the database and control strategy. In the case of spares from the warehouse or other APL devices without tag, the instrument technician could assign a tag from a laptop with APL interface or possibly a smartphone or tablet over Bluetooth, if supported. It is expected tag assignment will be possible through the webserver in the device from a web browser.

In the process industries, network time synchronization will be done using the standard Network Time Protocol (NTP) or Simple NTP (SNTP) protocols which have millisecond precision, sufficient for process control applications.

APL Commissioning

Bulk configuration download to multiple devices will be possible, for fast device commissioning.

Some modern application protocols, but not all, support automatic discovery of the underlying network infrastructure which will make use of Intelligent Device Management (IDM) software and other applications easier. Particularly for package units, skids, and Module Type Packages (MTP) etc. This will allow software users to browse their way to a specific device or variable without having to first manually recreate the plant hierarchy. This could potentially enable new innovative third-party software with never before seen functionality.

APL real-time control

APL networking will be high speed, so devices will be capable of real-time PV from sensors and setpoint to valves, for many devices and control loops. That is, APL devices will not just be about measurement. It will also be about throttling valves and on-off actuation. Make sure to use modern application protocols that supports interoperability for both process variable inputs and setpoint outputs. Not all do.

Some modern application protocols, but not all, are time-synchronized and scheduled to be highly deterministic; communicating real-time process values and valve setpoints separately from non-real-time configuration download, process alarms, and instrument diagnostic alarms etc. such that closed loop control is not affected by configuration download and alarm notifications etc. Scheduled communication will make it possible for control system to calculate the network load offline before the network goes operational.

Some modern application protocols, but not all, also support alarm management for process alarms detected in APL instruments and Ethernet devices.

Sensor 4.0: Composite Measurement Systems

Some modern application protocols, but not all, support peer-to-peer communications enabling composite measurement systems such that field instruments will be able to communicate directly to other field instruments. Technically devices could be on different networks provided they will be synchronized with the same SNTP server. For instance, one pressure sensor communicating directly with another pressure sensor to form a virtual remote seal. Or pressure and temperature transmitters communicating directly with flow transmitter for flow computation and flow correction for a two-wire intrinsically safe flow metering system. A transmitter in an inaccessible location communicating directly with a local display at eyelevel. A transmitter, valve, and a single loop controller communicating directly with each other for closed loop control.

APL real-time status

Process variables from APL devices will appear in the DCS operator screens just like from wired devices so no special training will be required for operators. Additionally, APL devices will also provide a real-time status for each process variable, which will have more detail status than provided by 4-20 mA devices (e.g. on sensor failure etc.). It would make sense to train operators to make use of this status. The level of detail included in the status will depend on the application protocol used. Moreover, every DCS has its own way of displaying and using process variable status. The status from the application protocol will map to the DCS’ status to a greater or lesser extent. In some DCS just “input open” alarm, in others the full status including high and low limit etc. Some modern application protocols, but not all, provide the status together with the value as a single parameter for ease of system integration.

The control system will monitor the communication health and alarm on communication error. There are modern application protocols that have DCS-style redundancy, but most don’t. Those that do, monitor for communication errors and alarm on both networks to make sure the backup is ready to take over.

APL cybersecurity

IP is different from conventional fieldbus communication in that IP is routable, meaning network switches will route messages from a device or computer, from switch to switch, across networks until the message reaches its desired destination address. Since with APL networking, IP will be used “from the shop floor to the top floor”, cybersecurity will have to be in place to make sure an APL network will not be used by hackers as an entry point to gain access to servers and devices elsewhere in the organization. Multiple solutions for IP cybersecurity exist. Some of these solutions will be built into APL devices, APL field switches, and APL root switches. Other solutions will reside at higher levels. These are the same IP cybersecurity mechanisms used with regular Ethernet. As IP/Ethernet cybersecurity solutions continue to evolve these solutions will also benefit APL devices. APL devices and control systems will be certified to ISASecure and Wurldtech Achilles just like Ethernet devices.

Note that cybersecurity is not built into the individual industrial application protocols. It would be impossible to manage cybersecurity if FF-HSE, PROFINET-IO, EtherNet/IP, HART-IP. and Modbus/TCP each did cybersecurity differently. Instead cybersecurity will likely be done at a lower level using Transport Layer Security (TLS) / Secure Socket Layer (SSL) encryption and IEEE 802.1x authentication such that the cybersecurity mechanism will be common for all devices regardless which application protocol(s) they are using for data transfer. This will also avoid duplication of effort. This provides authentication, autorizaiton, integrity, and confidentiality etc.

Just like other Ethernet applicaion protocols, the industrial Ethernet applicaion protocols each have a dedicated IP port. If there are any firewalls in the data path, the corresponding port must be open for the IP addressess involved. This also holds true for any proprietary application protocols used in the APL devices and software as well.

Some modern application protocols, but not all, use publisher-subscriber communication over UDP for real-time data transfer which lends itself well for use with data diodes since it does not require polling. In the future data diode vendors may develop data diodes specifically for these industrial application protocols.

APL functional safety

At first, APL devices will be used for process control and monitoring. In the future APL devices will also be used for functional safety, but will have to prove itself in process control first. Devices to be used in a Safety Instrumented Function (SIF) must be suitably certified to the required Safety Integrity Level (SIL). Eventually it will be possible to use the same field instruments for both process control and functional safety provided they are suitable functional safety certified (SIL). The type approved safety protocol addition will have to be enabled.

APL redundancy

It will be possible to deploy APL root switch and APL power supply in redundant configuration for high availability.

Some devices like remote I/O boxes will support redundant APL networking. There are modern process control application protocols that support full DCS-style network redundancy with two completely independent networks, redundant device pairs, and redundant Ethernet ports on each component – but most application protocols don’t. Other application protocols only support PLC-style “ring topology” which is not the same. The redundancy switchover time will depend on the application protocol used. Switchover in a control system with full DCS-style redundancy will likely be faster than a system using ring-topology since with DCS-style redundancy both networks run in parallel all the time so there is no change in communication path or addresses required. Since the redundancy mechanism is part of the application protocol, devices that require network redundancy should be chosen such that all devices on the network support the application protocol responsible for the redundancy.

In the future some vendor may create APL field switches and APL root switches which supports APL networking in a ring-topology. However, since a fault on a spur will not propagate to the trunk thanks to the repeater functionality in the APL field switch, and a fault on the trunk is unlikely as work will rarely be carried out on the trunk, it is unlikely ring-topology will be required for field instruments.

APL Interchangeability

Until now IP and Ethernet have been used in indoor devices like PLCs, controllers, and drives etc. which generally have very long lives and when they fail are typically replaced with an identical device. However, field instruments are different. They are installed outdoor and many are in direct contact with the harsh processes. Field instruments therefore have shorter lives (i.e. gets replaced more frequently) and may many times be replaced by another model device from another manufacturer. For this reason, interchangeability will be a crucial application protocol requirement for field instrumentation and the implementation of the application protocol in the control system software. Interchangeability means it is not necessary to change control system configuration when replacing a device with a new. For instance, a new version device must be backwards compatible with the older version device. Interchangeability also means you can replace a device with another brand without reconfiguring the control system. Interchangeability is technologically more demanding than interoperability. Over and above a standard object-oriented information model, standard data types, semantics, and device description files etc., to enable interchangeability, an application protocol also requires standard profiles. A profile means a defined subset of standard parameters in common for a device category like transmitters, or kind of device like pressure transmitters. Some modern application protocols, but not all, support standard profiles (including function blocks and transducer blocks). It is expected control systems will be implemented based on standard profiles such that the control system database will not be “locked” to one particular device model and version. This will make it possible for the control system to automatically bind a new device to the control strategy when connected, to receive sensor measurement values and transmit valve setpoints, even if it is a different model and version. This is possible because some modern application protocols, but not all, allows the control system to read device capability (supported function blocks and transducer blocks etc.) directly from the new device (without the need for DD/EDDL/FDI file) to determine if the new device will be able to take the place of the old device. This will make device replacement very easy, using only a screwdriver, without the need to touch a computer.

Some modern process automation application protocols, but not all, support the same standard core parameters (PV, unit, range, simulation, damping, tag, sensor type, setpoint, actuator type, diagnostic status, and change counter etc.) albeit by different name, data type, and enumeration. In the future, it could technically be possible to replace a device using one of these application protocols with a device using another application protocol, without manual reengineering, while retaining the core functionality provided by the device. However, advanced functionality of one application protocol may not map to another.

It is expected APL technology will be implemented differently from conventional fieldbus: the control system database will not be locked to a particular device type or version. The control system database placeholder will only be for IO profile like transmitter, or device profile like pressure transmitter.

Intelligent Device Management (IDM)

Some modern application protocols, but not all, support Field Device Integration (FDI) and the earlier Device Description (DD) and EDDL which are key device integration technologies for intelligent device management.

For some devices it will also be possible to configure etc. locally through Bluetooth, Wi-Fi, or regular Ethernet console port if the device has it. It will be possible to disable these interfaces to prevent inadvertent changes or malicious tampering. Some modern process automation application protocols, but not all, support configuration changed notification from devices enabling the central control system database to stay consistent with any changes made in the field devices locally through a laptop with web browser or app, or local display, and to keep an audit trail of when changes were made. That is, enabling centralized common change management for all devices in the plant to prevent inconsistencies between device and database.

Since APL devices will have an IP address, data will automatically be routed between the devices and software applications through multiple levels of APL network and Ethernet networks based on the IP address. There will no longer be a need for nested commDTMs and gatewayDTMs etc.

Because APL networking and Ethernet permit proprietary application protocols in parallel with the open standard application protocols, it is expected many APL device will also make use of proprietary application protocols. Associated with each of these devices with proprietary application protocols it can be expected there will be a software application for advanced diagnostics and other functions associated with the device.

APL Instrument Diagnostic Alarm Management

Device self-diagnostics is important to manage the large number of field devices in a plant. However, it is important that instrument diagnostics alarms do not flood instrument engineers and technicians, or operators. This requires instrument diagnostic alarm management. Some application protocols support NAMUR NE107 “Self-Monitoring and Diagnosis of Field Devices” instrument diagnostic alarm management. Make sure it is supported, with timestamp, in the devices and control system and IDM software you will use.

Intelligent Device Management (IDM) software shows more detail diagnostics than the status associated with process variables; each individual device issue will be distinguished.

Cloud

APL device communication will be fully routable thanks to UDP/TCP/IP so data will be able to go from field instruments all the way to the cloud without gateways and application protocol conversion. Note that MQTT, AMQP, and CoAP etc. are not required for cloud connection. This will be useful for Industrial Internet of Things (IIoT) based connected services.

Next Generation Field Instrumentation Capabilities

Because APL networking is fast, 10 Mbit/s, it will be capable of transferring a lot of data such as web pages with illustrations or PDF files. This will enable the next generation of field instruments based on APL technology to have new features not found in today’s 4-20 mA and on-off devices. These new features will save instrument technician’s time. Many of the features a device can provide will depend on the application protocol(s) the device support and what capabilities the device manufacturer implements.

Central firmware update

It is expected APL devices will have the ability to update firmware on the fly from a central software to enable plants to take advantage of new features and other improvements. Some modern application protocols, but not all, support a standard firmware update mechanism. Some devices will support bumpless switchover from old firmware to new. This will solve the problem of centrally updating firmware in devices across the plant to benefit from new functionality in the device and for cybersecurity patches.

Device webstore

In the future, device vendors will likely have online webstores similar to Apple App Store or Google Play store for smartphones, selling in-device apps like additional advanced diagnostics and function blocks: the “apps” of automation. This will solve the problem of unlocking optional functionality in devices based on license when you discover after installation you need functionality you did not originally purchase, or when manufacturers make new functionality available.

Instruction Manual in device

Vendors have already demonstrated APL devices that store the instruction manual and other device documentation in the device itself, matching the exact version of the device. Central software or ad-hoc connected laptops and mobile devices will be able easily upload these documents. This will solve the problem of getting the correct document matching the device version at a click of a button, even when there is no internet connection. There will be many ways of achieving this; I personally believe it would be best for plants if a single common way of organizing and accessing documents stored in devices was agreed upon.

DD/EDDL/FDI in device

It is likely many APL devices will store their matching DD/EDDL/FDI package in the field device itself. Some modern application protocols, but not all, support a standard mechanism for automatic uploading of DD/EDDL/FDI package stored in device into control system software. This way the Intelligent Device Management (IDM) software will automatically upload the package from the device itself when the device is connected. This will solve the problem of getting the file of matching device revision making device replacement easy. An APL device supporting multiple application protocols will also have to store multiple files to support these application protocols. An FDI package may also include device documentation.

Web browser interface

Many Ethernet devices already have an embedded webserver. It is anticipated APL devices will be the same. This will enable configuration, calibration, diagnostics, and to otherwise manage the device from a web browser over HTTP or HTTPS protocol as opposed to over one of the industrial application protocols. Configuration through web browser does not require DD/EDDL/FDI file or FDT/DTM programs. This solves the problem of getting specialized device configuration software, DD files, or DTM programs. I personally believe web server access control will be crucial as you don’t want everybody to access the device configuration.

Note that device vendors design their webserver interfaces with their own unique menu structure and their own individual color scheme and style. This means the web-based user interface navigation look & feel for every device type will be different and therefore will take longer to learn. Device configuration and management tools based on EDDL or FDI (unified EDDL) provide a more consistent look & feel; a manufacturer independent user interface because graphical elements are rendered by the device-independent software. For instance, coloring such as to highlight parameter changes that need to be downloaded, parameters that mis-compare, and diagnostics failure is determined by the IDM software, not each device manufacturer.

It should be noted that a web server user interface will not be an effective way to configure large number of field instruments since parameters must be entered one by one, device by device. Depending on the application protocol, control systems will support bulk configuration download.

It will be possible to disable and write-lock the device webserver as read-only to prevent inadvertent changes or malicious tampering.

For some devices will also be possible to access the webserver through Bluetooth, Wi-Fi, or regular Ethernet console port if the device has it.

New Kinds of Devices

The higher current capacity and real-time digital communication of APL networking will enable improved I&C devices and new kinds of devices to solve problems around the plant.

• Make existing device types better
• Create new kinds of device classes (including new advanced sensors)

Classic Instrumentation Made Better with APL Networking

Some plants today use dedicated RS485 networking for electric actuators / Motor Operated Valves (MOV), another for flow meters, one for each silo with 3D solids scanners, and yet another for temperature multiplexers, corrosion monitors, ticket printers, a.s.o. to get the full functionality of these devices with minimal wiring, not possible with 4-20 mA and on-off signals, such as totalizer. In the future these devices will share the same APL network as other field instruments. This will solve the problem of dedicated networking for specific devices. Many, but not all, of these will also be powered by the APL networking not requiring separate power cable.

Similarly, today some plants use a small number of field instruments with regular Ethernet like custody transfer flow meters. In the future these field devices too will share the same APL network as the other field instruments. Thus dedicated Ethernet cabling for a specific device won’t be required. Various kinds of liquid, flue gas, and process gas analyzers will use modern open standard application protocols that support NAMUR NE107 instrument diagnostics alarms (not all do), configuration change management, and other common functions. This will solve the problem of dedicated Ethernet for specific devices.

In the future pressure transmitters may have auto-ranging sensors – the same transmitter will cover a wider pressure range. This will solve the problem of having a large inventory of many sensor ranges to cover various applications, enabling reduced inventory, and also providing better accuracy at low values, as well as providing a measurement value at high pressures in abnormal conditions.

Similarly two-wire flow meters will have more power for flow tube drive signal which enables higher turndown ratio. This will solve the problem of two-wire flow meters not being accurate at low flows. Larger pipe sizes will also be covered by two-wire flow meters.

Addressable (networked) fire & gas (F&G) detectors today use proprietary application protocols and therefore require dedicated networks. Multiple networks are required to cover the various kind of detectors for flame, smoke, and various gases. In the future F&G detectors of various kinds will all use standard, two-wire bus powered, and intrinsically safe, APL networking - all sharing the same network; the same network as the other field instrumentation. This will solve the problem of dedicated networking for some detectors and thus will be more economical to deploy, with more detectors for better coverage in crammed spaces like FPSO/FLNG, making the site a safer place to work. Future device replacement will also be easier.

Process induced measurement noise is a problem for many sensors today. But with more power for the microprocessor for more advanced signal processing with future APL networking, perhaps sensors in the future will become better. It will even be possible to send raw data to a server for further analytics to get good results. Perhaps clamp-on non-intrusive ultrasonic flow meters will get sufficiently high performance for applications like heat exchanger monitoring, mass balances, energy balances / Energy management System (EMIS) etc. This will solve the problem of having to cut and weld pipes or otherwise disrupt the process to get a reliable flow measurement.

Pressure drop, flow, vibration, and acoustic noise are useful inputs in detecting and predicting valve failures. However, they are rarely if ever measured. With APL networking it will be more practical to measure and integrate such external variables into future valve diagnostics software for more predictive and prescriptive analytics. This will solve the problem of recreating valve diagnostics in general purpose data analytics software.

Future APL devices may have full brightness backlit LCD display on all devices including two-wire devices which will make it easier to work with these devices. APL devices may even have LED display. APL devices will also be able to bring attention to internal or external problems by blinking the display or by colored LEDs. This will solve the problem of working locally with two-wire devices.

In the future with APL devices it will be possible to fully utilize the auxiliary variables in devices; such as the ambient temperature measured by most if not all devices. This will enable software to take the ambient temperature reading from the ambient temperature sensor in every instrument to form a thermal map of the entire plant. This will solve the problem of predicting buildup to a fire or fire hazard, by detecting abnormally elevated ambient temperature early. Most field instruments have such auxiliary variables already today, but they usually go unutilized because most instruments are not digitally integrated.

Future Classes of Field Instruments

Some think of a real-time digital field network as just a replacement of 4-20 mA and on-off signals using digital communication with the same kind of field instruments. I personally have a vision much greater than that; a future including a whole suite of new kinds of field instruments never seen before, providing entirely new capability never seen before to solve problems not solved before.

The industry sentiment is that “smart” devices are not very smart by today’s standards. Setting the range in a pressure transmitter without applying an input was amazing 30 years ago. Today we expect more from a “smart” device. Other time-consuming tasks should be eliminated or simplified in similar ways. By doing away with 4-20 mA and on-off signals, going fully digital, field instrumentation will finally start benefitting from Moore’s law.

The expectation is that digital networking will bring sensor-systems of multiple sensors. High bandwidth will bring advanced sensors like still images, streaming video, and audio clips etc. These will solve new problems around the plant.

The industry expectation for new smart devices is something equivalent to the breakthrough brought about by the mobile phone network; not just a phone for calls which is mobile, but once the GSM network supported GPRS data the smartphone appeared and it is really a full-fledged computer – which, among many things, you can also make calls from. This is why the most successful handsets are made by computer companies not by those that made telephones or walkie-talkies. So the expectation for the future is not just better transmitters, it is new classes of devices.

Digital Transformation (DX) among other things means many tasks which until now are being done manually with portable testers will instead be done automatically by permanently installed sensors. Common examples of this includes vibration, temperature, acoustic noise, and corrosion (wall thickness) etc. Yet another new example of this will be audible noise level. In the future plant noise pollution will be monitored with an array of noise sensors using APL networking, sharing the same network as the other sensors around the plant presented as a heatmap of the plant to identify noisy areas. This will solve the problem of noise pollution; hearing protection for plant personnel and tranquility of neighboring communities, meeting ever more stringent regulations. The abundant power and high bandwidth of APL networking may also enable noise spectrum analysis possibly identifying the source, and possibly predicting process and equipment problems from changes in noise patterns.

In the future, perhaps there will be two-wire IR cameras for liquid leak/spill detection sharing the same APL network as other devices. This will solve the problem of labor-intensive manual surveillance and reduce hazards.

Machine vision has been used in discrete manufacturing for years. Perhaps in the future there will be machine vision for the process industries; two-wire cameras sharing the same APL network as other devices. Possible applications include flaring, smoke, and intrusion detection, as well as PPE recognition. This will solve the problem of labor-intensive manual surveillance, reduce hazards, and improve security and safety.

Instead of portable thermographic cameras, in the future there may be permanently installed two-wire thermographic cameras sharing the same APL network as other devices for transmission of thermographic images to automate manual inspection. This will solve the problem of monitoring reformer tubes and walls inside of furnaces etc.

Future flow meters sharing the same APL network as other devices may also measure process pressure and temperature using only two-wires enabling compensation as well as analytics such as heatmaps and plausibility checks. This will solve the problem of additional process penetrations, wiring, and associated cost for flow correction.

Similarly, two-wire level transmitters sharing the same APL network as other devices may in the future also measure pressure and temperature enabling compensation as well as analytics such as heatmaps and plausibility checks. This will solve the problem of additional process penetrations, wiring, and associated cost for level correction.

With APL networking, blind single loop controllers could execute control installed anywhere and seen from everywhere. This will solve the problem of large Ethernet connectors and bulky Ethernet switches for small controllers.

In the future, some Wi-Fi access points may share the same APL network as field instruments in places hard to reach with Ethernet or PoE. An economical solution using only two wires. This will solve the problem of Wi-Fi coverage for wearable helmet mounted video cameras with streaming video or fixed video camera devices in remote corners of the plant.

Future APL devices sharing the same APL network as other devices may include two-wire camera that will snap a still image triggered on motion or other change. This will solve the problem of monitoring the security perimeter and for detecting changes in process area. It will be possible to use such information to direct CCTV cameras.

Field mounted two-wire vibration transmitter sharing the same APL network as other field instruments may in the future support vibration sensors for three axis and temperature with continuous sampling to predict quickly developing problems early using embedded FFT edge analytics. This will solve the problem of labor-intensive manual surveillance of every pump, fan, motor, gearbox etc. It will be possible to livestream vibration spectrum, waveforms, and orbits etc. watching it like video when troubleshooting a machine.

A future two-wire electric motor condition monitoring transmitter sharing the same APL network as other devices may monitor magnetic flux on a motor through a flux coil, with FFT edge analytics in the transmitter and FFT spectra analysis app. Other sensors may pick up stator and winding temperature, and optionally 3-phase motor current and shaft voltage. This will solve the problem of labor-intensive manual surveillance.

Future APL devices may include two-wire mic that will record a soundbite triggered on sudden noise or other change in machinery and pump noise or safety valve pop and transmit the audio file across the same APL network as other devices to be reviewed centrally. This will solve the problem of keeping track of what is going on in the plant which cannot be detected using traditional sensors and have relied entirely on human senses and manual patrol.

Future APL devices may include two-wire video camera that will record a videoclip triggered on movement or other change and transmit the video file across the same APL network as other devices to be reviewed centrally. This will solve the problem of keeping track of what is going on in the plant which cannot be detected using traditional sensors and have relied entirely on human senses and manual patrol.

One of the roadblocks to the introduction of new sensing technology in plants is the need to provide associated infrastructure such as dedicated network. It’s not practical to run Ethernet just for one kind of sensor. Particularly in a hazardous area. With future APL networking you will just need this one infrastructure in place to deploy any type of APL device in the plant, including in hazardous areas. Light Detection and Ranging (LiDAR) is one such possible technology. Two-wire LiDAR sensors may be installed permanently sharing the same APL network as other devices for continuous monitoring for changes; not just one-time plant mapping. This will solve the problem of policing obstructions along evacuation routes or fire engine access or fire exits, detect pollutants in the air, monitor movements in the plant, especially in the dark, such as unauthorized entry and vehicle speeding.

Manual IR thermography with portable testers has been done in plants for decades using portable testers for electrical switchgear and equipment. Perhaps in the future there will be permanently installed two-wire IR thermography cameras sharing the same APL network as other devices. Other possible applications include detecting hotspots on vessels, reformers, and predicting exothermic reaction runaway reactors etc. This will solve the problem of labor-intensive manual surveillance and improve reliability.

In the future, intelligent light fixtures around the plant and inside unmanned buildings may be networked using the same APL network as field instrumentation. Motion sensors may detect movement and adjusts light accordingly for energy saving. Lights may change color to indicate no entry during danger like H2S or best evacuation route based on wind direction. This will solve the problem of communicating to plant personnel which areas have high-risk status, and reduces energy consumption.

Future process on-off valves will be intelligent, sharing the same APL network as control valves, MOVs, and other field instruments. Using only two wires for control and feedback signals as well as power. They will provide diagnostics like travel time, breaking free torque, and condition of the solenoid. This will solve the problem of

Automatic Overfill Prevention System (AOPS) will in the future be a two-wire system of multiple sensors sharing the same APL network. This will solve the problem of unprotected storage tanks, making the plant a safer place to work.

Equipment condition monitoring will in the future be a two-wire system of multiple sensors sharing the same APL network as other field instruments. For example, on a smart pump you may find bearing vibration and temperature transmitter, strainer DP, discharge pressure, mechanical seal flush reservoir pressure and level, magnetic flux, stator and winding temperature, motor current, and shaft voltage on the same pair of wires. This will solve the problem of labor-intensive manual inspection.

Migration to APL networking: from “H1” to “T1”

The APL technology is backwards compatible with common fieldbus cable because both use shielded twisted pair AWG #18. Therefore it will be possible to transition an installation of common fieldbus devices to APL technology reusing the same cable and network topology.

Some manufacturers have demonstrated APL field switches that support both APL devices and H1 fieldbus devices at the same time. That is, it will be possible to connect FOUNDATION fieldbus and PROFIBUS-PA devices to the same APL field switch as APL devices. The APL field switch automatically detects if it is a common fieldbus or APL device connected. An embedded proxy represents a common fieldbus device on the APL network. So, if a plant wanted to migrate from common fieldbus to APL technology, the fieldbus coupler or fieldbus barrier in the field junction box would be replaced with an APL field switch. In the future it might be possible for manufacturers to support APL networking and H1 in the same device.

In the control cabinet the PROFIBUS-PA link or FOUNDATION fieldbus card would be migrated to an APL root switch. The controller firmware may have to be upgraded to support IO over Ethernet. Some control systems may need an Ethernet interface card. Lastly, the control system software will have to be upgraded. Periodic control system firmware and software upgrade is common anyway.

New Tools and New Digital Ways of Working

The whole purpose of deploying digital technology is to enable digitalization/digitization of how work is done in the plant, for the better: this is the Fourth Industrial Revolution (4IR).

Transmitters are digital, control systems are digital, and valve positioners are digital – so it makes sense to use digital communication between them to complete the chain for a digital closed loop. In the first plants that will deploy APL control systems, some field instruments will have to be fieldbus because not all types of devices will be available in an APL version yet, but since APL field switches will also support fieldbus devices, they will be able to coexist. Such fieldbus devices can be replaced by APL devices in the future as and when they fail.

APL networking doesn’t mean that layers in the Purdue/ISA95 reference model will disappear, it simply means that all layers, including layers 0 and 1, will use Ethernet in some form from bottom to top

Future ways of operating the plant will include the use of additional process measurements thanks to the lower cost of including additional transmitters in place of slow and labor intensive manual field operator round data collection, as well as real-time auxiliary measurements from the transmitters for better situational awareness for the process operators; giving them a better understanding of what is happening in the process based on additional pressure, temperature, and other measurements – for the purpose of reduced off-spec product, greater throughput, greater safety, as well as lower cost of operation. For instance, in-process quality control, as opposed to post batch lab analysis quality inspection, requires more sensors real-time pH, color, and viscosity etc. Other examples include getting a temperature profile instead of single point temperature on gas turbines, boilers, furnaces, reactors, LNG tanks etc. As well as mutual plausibility checks between sensors to detect false readings. By collecting auxiliary data from around the plant it will be possible to display “heatmaps” to visualize what is going on in the plant, and feed data into analytics.

Future ways of maintaining in the plant will include Intelligent Device Management (IDM) practices such as predictive analytics for discrete instrumentation enabling predictive maintenance in on-off valves etc. It will also include use of additional equipment sensors thanks to the lower cost of including additional sensors in place of infrequent manual inspection rounds with portable testers – in order to reduce downtime and maintenance cost, improve energy efficiency, as well as for more effective turnarounds.

Future ways of plant automation design will not require I/O card and safety barrier type selection, or signal marshalling design. There will be no gateways, device drivers, and data mapping. Late design changes like adding devices, device signals, and change of the kind of device will be easier.

Future ways of device pre-commissioning will include automatic loop check, documentation, and configuration download in discrete devices

Instrumentation and control (I&C) engineers have a very exciting future ahead with APL technology. But it is in future. APL devices are not available yet. But it is important companies accommodate new technology in their new plants.

At least 40% of all businesses will die in the next 10 years... if they don't figure out how to change their entire company to accommodate new technologies

- John Chambers, Executive Chairman, Cisco Systems

The future is digital; build control systems which truly are digital, without analog and on-off signals. APL networking for instrumentation will be used mostly in new greenfield plants and new extensions in existing plants but will occasionally also be used in plant modernization. A digital instrumentation network benefits operations, maintenance, and even the initial greenfield project.

New ideas pass through three periods: 1) It can't be done. 2) It probably can be done, but it's not worth doing. 3) I knew it was a good idea all along!

- Arthur C. Clarke

What new kinds of devices or functionality would you need in your instrumentation to make your plant run better or make your work easier? Well, that’s my personal opinion. If you are interested in digital transformation in the process industries click “Follow” by my photo to not miss future updates. Click “Like” if you found this useful to you and “Share” it with others if you think it would be useful to them.