Hi all, I've just bought and downloaded the latest TS2015 4EPB as I just love the slam door stocks. Whilst they have done everything in their power to get the EP brake working correctly (and it does as far as I can tell), I'm not sure the throttle physics are correct. Now correcty me if I'm wrong but I thought these stocks were camshaft control much like the 38TS and D78. This means as you motor up throught the notches via a notching relay, if you pull the MC handle back a notch it prevented further notching and holds that resistance in the motor circuit until you moved the MC handle on again thereby preventing further acceleration if it isn't required. The MC handle has 5 positions on this stock. Off, Shunt, Series, Parallel and Weak Field. My question is, does the control on these EMU's actulally work the same as the tube stock PCM or have I got this all wrong. When motoring in series and moving back to shunt or motoring in parallel and moving back to series you just keep accelerating until you actually move all the way back to the Off position. Doing 30mph in Off and then moving to Shunt you start accelerating, all be it slower but this has to be plain wrong. Just makes me think what a cracking job you did with the Standard Stock, D78 and 73TS scripting Jimi.
I'm duly flattered, but I do recall us both debating what should happen, notching behavior, etc. I just coded what we jointly deduced :-) I have to feel this is wrong. As we know in Series we're delivering half nominal voltage to the motors so there has to be a balancing speed (back EMF = applied voltage) for that supply voltage meaning further acceleration won't happen. Same with Shunt. My recollection of the notching behavior is if you moved the control back to Series/Shunt was it stayed in current notch until Parallel was selected, else notch back to zero if Off selected and then re-notch back to the appropriate series or parallel notch for speed if motoring re-selected. Maybe Roger could tell us more - anyone seen him lately?
That's what I thought. Reading on UKTS forum, they also come to the same conclusion for the Class 455 EMU. I Cannot believe they could sill have this wrong. Just like the DMU gearing, these people are model creators and I suppose know little on the control side and the physics. Shame really. I might see if I can copy some of the script components for the MC handle of the Standard Stock into a new one for the 4EPB to try and get it working correctly. Incidently, I thought Dave Brindley did a 4EPB model and he was a really good script writer. I remember him doing one for the IOW Class 483. I'm sure his 4EPB Script must have been correct.