Lessons Learned...a life in Engineering (part 3)

Welcome back to part 3 in this series of memories and lessons learned during my thirty-plus years of being an Electrical Engineer.

We finished last time when the Kevlar project in Londonderry was completed, which effectively saw me through my six month probationary period with Siemens at which point I was considered to be a proper employee and was entrusted to order my first company car (a nice bright red Ford Orion 1.6GL...I remember specifying “any colour except yellow”) and I was also issued with my first ever mobile phone which was the size of a couple of house bricks and weighed about twice as much. It came in a snazzy leather shoulder bag which suited my mother beautifully but she couldn’t even pick it up and one thing was for sure...this was not being carried anywhere over my shoulder. In the end I settled on carrying it around in a plastic Tesco carrier bag when I was on-call to avoid the embarrassment of people noticing it, seeing as mobile phones were as rare as rocking horse shit in those days and very, very expensive. So, it was not at all embarrassing when the phone rang during the quiz at my local Gateshead pub one Monday evening...

Anyway, the next project I ended up being involved with was the commissioning of seven Engine Development Test Beds for what was then Austin Rover at Longbridge, near Birmingham. These were seven completely separate test cells, all linked together with process computers which probably had less computing power between them than your typical mobile phone today. Each cell centred around a high speed DC motor / generator known as a dynamometer, capable of operating at well over 8000rpm with control loops for dyno speed, dyno torque, engine speed, engine torque and engine throttle position. A Simatic S5-115U plc controlled the testbed and its auxiliaries such as fuel, ventilation, combustion air, throttle servo, etc, and the drive system was an analogue, four quadrant Siemens Modulpac-C DC-drive with a host of option boards to enable the dynamic response and the additional functionality required for the system. Lots of the signal processing was done on Simadyn C cards which are effectively operational amplifier circuits and relay cards, which allowed for customisation of the circuitry and on-site modification of the design, of which many were necessary as the specification evolved significantly between order placement and final handover (to be fair, we were adding functionality to these testbeds for years after handover...). One of the major modifications required centred around a tie-up between Austin Rover and Honda at around this time and we were asked if we could make this work with a Honda engine. That sounds easy enough, however there was a fundamental difference between a Honda engine and a Rover engine at the time...one turned clockwise and the other turned anti-clockwise, meaning a massive amount of analogue signal polarity inversion needed to go on behind the scenes in the control panel. Given that the subracks were wire-wrapped this was a massive job and took weeks of mind-numbing unwrapping and re-wrapping of the connections and additional testing which set us back quite some time, but in the end the only visible change to the operator was a switch on the desk that selected between a Rover and Honda engine type. Lesson number twelve...something that appears to be simple is not necessarily so. Especially in the project world, where all of this additional time needs to be appraised, accounted for and paid for by somebody as there is a good chance that it is not included as part of the contract scope. An even bigger issue is that contractual delivery dates can be severely compromised by doing work that is outside of the contractual agreement, and formal variation-to-contract procedures need to be followed to ensure everything is taken care of for the lawyers. Failure to do so means you can easily run into penalty situations which are not good for the project nor the customer / supplier relationship, which is generally fundamental to the successful implementation of anything in my humble opinion. Lesson number thirteen, then, should be to keep a detailed diary of daily events and tasks...down to the minute, if necessary. I still use a page-a-day diary to this day (although I have recently downsized from A4 to A5 size), old habits die hard !

Around this time we also managed to win a series of contracts with a paper-converting machine manufacturer based in Taunton, where we supplied the DC drive system comprising of an unwind stand, two rewind stands and the PLC controller for the machine. Now, we had done a couple of these before by all accounts however I'm not convinced that they worked well, based on what I learned as we went along...

There was an additional analogue control board attached to what was the first-generation digital DC-Drive (the Simoreg 6RA22) which performed the necessary calculations (if that is the correct term) for the winder / unwinder technology. Basically it was an integrator which compared the rotational speed and the linear line-speed in order to calculate the diameter of the reel on either the rewind or the unwind stand. One of the potentiometers on this board that required setting-up beforehand was for the build-up ratio which effectively meant taking the diameter of the cardboard core used to wind the paper onto, dividing this by the maximum reel diameter, and scaling this to 10V. Now I can't remember the real numbers but let's say that the reel was 95mm OD, and maximum reel size was 1600mm, this means the pot needed to be set at (95/1600) x 10 = 0.59V. Now...remember lesson four, don't believe anything that you haven't made up yourself ? Well, before I'd set-off to sunny Taunton for pre-commissioning, I'd had a 'teach-in' with one of the so-called 'experts' on this option board who had told me "don't read the manual...set it for 6V and add another four big capacitors to the integrator feedback to slow it down. It'll be fine”...well, you can probably guess that it wasn't. It all started fine but after winding about 50mm onto the core it started to go unstable and instead of having straight sides all the way up the new reels, it looked like a washboard. Not good at all...and the customer is preparing to load a huge ￡30k reel of top quality coated carbon-less copy paper onto the machine. Time for a swift exit, and lesson number fourteen...when all around you are losing their heads, and running around like absolute idiots panicking about the situation...take a dump. Seriously, I can't begin to imagine how many problems I've solved when I've been sat on a toilet, but it will be a significant number. I find it a really good place to sit and think, make a plan, and a really good place to read the manual without getting interrupted by people who are just talking for the sake of talking. I can wholeheartedly recommend it when you are scratching your head wondering what to do next. 

And in case you're wondering what happened...I read the manual, set the build-up ratio potentiometer to the correct value, it worked like a dream, and the customer took the unprecedented decision to ship the slitted reels back home to France whereas he would normally have scrapped them as the first ones usually are not worth keeping. 

Now, as anyone who knows me will testify, I do like a curry and I can remember rewarding myself with my first ever vindaloo during this trip. I drove from my hotel the couple of miles into Taunton and sheepishly ordered the hottest thing on the menu. In it went...and it managed to work its way through my digestive system before I could even drive the couple of miles back to the hotel. Why is it that hotels always...without fail...put me in the bedroom that is furthest away from reception ? I made it back to my room, just...but then the world fell out of my bottom, and I've been hooked on spicy food ever since. Lesson number fifteen...clock the location of the foyer toilets when you stay in a hotel, it may come in useful. An incident in the Crowne Plaza hotel in Ningbo, China, twenty-odd years later confirms this point...after the wonderful Pakistani chef's speciality 'Boom-Boom Chicken' I made it to the foyer toilet with milliseconds to spare before the 'Boom-Boom' took effect, my colleague who went straight for the lift to his room on the 24th floor was not so lucky and managed to follow through in the lift. The plumbing in that hotel is another story and both of us managed to suffer lavatorial blockages that evening but I will spare you the details of that...for now. I might bring it up again when we eventually get to 2013.

Anyhow...back to 1989, and on to the next converting project (after commissioning the previous one in France and modifying its sister-machine to work properly with the right build-up ratio, and getting it to be stable at full speed which was something like 1500m/min). True to form, rather than copy something that worked very well, our design team had to perform some jiggery-pokery with the design in order to complicate matters...and to clearly get the costs down. This time, we had field weakening on the unwind stand and a different firmware version (v3.3...sad, I know) on the Simoregs. This commissioning should have been the simplest thing in the world, however the field-weakening was a bugger to set up initially (once I had worked out how to do it when working with a tension loop it was actually really easy) and the new firmware threw several time-consuming spanners into the works, the hardest one to fathom being that when you selected a main speed reference ramp-rounding function (we used a three second rounding on a two minute ramp...) the DC drive would run away when you used the jog function...absolutely bizarre and I still have no idea how and why the two functions were even linked...but they were. New firmware please, and lesson number sixteen...new versions of software and firmware are recipes for disaster and will never work without problems, so be prepared for heartache no matter how straightforward you believe your task appears to be !

So, pre-commissioning in Taunton went relatively easily so then it was off to a place on the Dutch / Belgian border for installation and commissioning, where the beer was extremely strong and the walls were very hard when you bounced off them when in an advanced state of refreshment (my favourite was called Kwak...and it came in a little baby yard-of-ale type glass in a wooden stand to allow the glass to stand up. It was absolute loopy juice...). Unfortunately, the Mechanical Engineer who was working with me wasn’t able to keep up with my advanced drinking capabilities although, give him his dues, he tried really hard. Mornings were not good for him at all, and eventually he threw in the towel and just disappeared. I’ve not seen or heard from him since. Lesson number seventeen...beware the Kwak. I did stop drinking alcohol back in 2002, and to be fair it was one of the best things I ever did. I don’t preach to anyone about it (unless they ask to be preached to...) but nearly sixteen years without a hangover, or doing anything really stupid has probably been the best thing for all concerned...especially the Mechanical Engineers.

Onwards and upwards then, towards episode four...marriage followed immediately by an eighteen month honeymoon in a Redcar steelworks. Let’s speak again soon...