If you AMP meter was to fill up, it would mean you're generating more electricity than the traction motors can convert, and you'd blow the traction motors. How are you unlocking doors on the train? Are you using the D-pad menu, or pushing buttons in the cab? Which route are you using the Class 47 on?
Do you leave the throttle on when applying breaks as when the throttle is in the on position and the loco is static the apms are pretty high. If the throttle is still on this may casue it to happen. Alternativly you could accidently be taking it out of gear or putting it in reverse. I've done this many times with the 101 but haven't on the 47. I'll test these out and get back to you.
I've tried some different things and found that the most likely cause for the engine cutting out is leaving the throttle over 20% whilst applying the breaks, this causes this amps to rise to try and keep the loco moving. Eventually the get to high so the engine cuts out. I'd turn the throttle off at least a mile away from the station and not put it on again unless I had under shot. Hopes this helps.
It is what is called a flashover, it completely fries the traction motors and you'd end up having a failed loco on your hands.
There is no in cab buttons for any of the locos on NTP and most of the older routes and locos in TSW and TSW2. (excludes Tube '72 stock and Isle of White)