The Future of Powering the World

The National Fire Protection Association (NFPA) in the United States updates and publishes the National Electric Code (NEC) every three years. The NEC is highly regarded as the authoritative standard for electrical safety. This year, the NEC introduced a new class of electricity, Class 4 Fault Managed Power. Although we are just at it's infancy, we can already see that the introduction of this new class will have major impact in the future.

The four classes of electricity include:

• Class 1 - High voltage circuit up to 600V that must be handled by a certified electrician
• Class 2 - low voltage circuits capped at 100W
• Class 3 - up to 300V capable of causing electrical shock with additional safeguards does not pose a fire hazard typically used in PA and security systems
• Class 4 - can carry up to 450V safely with continuous fault management that does not have a 100m length limit (as found in IEEE standards for Power over Ethernet)

Class 4 power is going to have an impact on how power is delivered, distributed and utilized. Today high power transmission lines brings power to a structure from a source. This AC power is then distributed throughout the structure, usually interfacing with equipment that requires power through electrical plugs; however, if we take a look at what is plugged in, much of it is not running off of AC power. Yes there are large equipment such as refrigerators, washers, dryers, dishwashers, and HVAC systems that run off of AC. Yet, as I look around, there are many more that are running off of DC.

The computer I am typing on, my cell phone, and printer all have a power unit that is converting the AC to DC. Each time this conversion occurs, there is a loss of power. And there are many more devices in the modern home that can be run off of DC. These include security access and cameras, wireless internet access points, LED lighting, and even TVs. As a matter of fact, most home devices can run off of DC power.

Since 1997, with the introduction of Power over Ethernet (PoE), we have seen an increase in the number of devices that can be run off of DC power. The IEEE has established the standards of 802.3af, at, and bt on how this DC power can be delivered over an Ethernet cable. PoE, a Class 2 power, with additional safety features such as a "handshake" to deliver power only when requested, was first introduced by PowerDsine, which today is the Microchip PoE Business Unit. The first device to take advantage of PoE was the IP Phone. Over time PoE was used to power IP Cameras and Wireless Access Points. Today, PoE can power hundreds of devices.

PoE has many advantages including:

• International Power Standard - delivered through one interface, RJ45 connector
• Reduced Installation Costs - no additional infrastructures such as conduits are required and does not need a licensed electrician to install
• Flexibility and Scalablity - it is easy to run up to 100 meters of ethernet cable and can be easily rerouted when needed
• Remote Power Management - a feature available on many PoE devices providing power, especially those with multiple ports so power can be turned on and off when required
• Safe Power - besides being low voltage and only up to 90W, PoE never delivers power unless a request is made from a device

So as we reimagine the electrical infrastructure a new approach is emerging where:

• High Voltage AC electric lines will deliver power to a structure
• The majority of the power will be converted once Class 4 fault managed power to reduce loss
• Class 4 power will be distributed throughout the structure because PoE has a limit of 100 meters whereas Class 4 has no limitation
• Class 4 power will then be used converted to Power over Ethernet and delivered to the end devices

Since Class 4 is a form of DC current, the conversion from Class 4 to PoE has a minimal energy loss. And since so many devices are powered by PoE today, the path for the quickest adoption is to take advantage of all that can be powered through PoE today.

If you think this is some dream, it is already being used today. There is at least one vendor who is supplying Class 4 power, VoltServer, and there are several more working on it. In addition, the UL has established the industry's first certified Class 4 cabling system; UL 1400-2. There are hotels, schools, stadiums, and even casinos that are using Class 4 power.

So as we look to the future, Class 4 Fault managed power is definitely going to have an impact. I am interested in learning what you think about this introduction and how it is going to impact the future.

#Class4faultmanaged #Poweroverethernet #PoE #NEC #NFPA