Recent content by matrixabc

The Under voltage coil should be fed from the upstream supply, it needs to be energized to allow a "shunt close" if there is no power the coil will de-energize and trip the breaker open.

some manufactures, don't offer PMG, and they will argue that there is no determent to auxiliary winding over PMG, but they can not guarantee that if the set was left for a long period of time(months) it would excite every time, and you may have to flash the field, but a PMG is guaranteed.

Is the AVR designed to run at the lower voltage?

Could be static, you have to watch out as there will be hydrogen gas, when you open the vents, I have seen a few blow up, and can be very dangerous in confined spaces, spraying sulphuric acid everywhere.

Thanks for the comments, I am going to install the intertrip, it makes sense , there is a generator, so it will prevent the possibility of back feeding in to the faulty transformer. Regards Matrixabc

If you Parallel a generator with the grid you must not connect the star point of the alternator winding to earth, other wise you will get circulating current through the parallel earth and neutral paths, we would fit an neutral earth contactor. open in parallel and closed at all other times.

Yes, I can see that but if the HV is off then it would be isolated anyway as there would be no other power source?

All the new synchronizing generator controllers will parallel any size sets together, via can bus connections. I used to have to use droop on old machines, but you have voltage droop and speed droop, you also have to make sure they have the same winding pith on the alternator other wise you...

My interpretation of closed transition "Passive "would mean the generator is set as close to the mains voltage as possible, voltage and frequency, normally just a bit higher, the switch will detect when they drift in to synch then fire the breaker closed in parallel then open the other all...

If you have an HV breaker 11kV feeding a 11kV/400VAC transformer, and no breaker on the output from the LV side, the cables go directly to the switchboard, I have normally seen an inter trip to the LV breaker if the HV trips out. I have recommended this to a customer but cant think exactly why...

On a 50Hz 4 pole generator 1500rpm (diesel)400/231vac up to 2.5mW we use 0.8.

I'm Not sure which suppliers are in the USA but for alternators try: Newage, Mecc-Alte, Marathon, SEG, Merreli, Leroy somer, Stamford(newage). I would recommend Newage, they are owened by Cummins.