50kw diesel generator 12 lead, from 120/208 to 277/480
50kw diesel generator 12 lead, from 120/208 to 277/480
(OP)
Hello all, i've been watching forum for a while now. There are very good and interestng posts here. I finally built up the courage to ask my first question, so here it goes. I need to rewire a 50kw diesel 12 lead generator from 120/208 to 277/480. The generator is now wired as 120/208.(1&7 to L1) (2&8 to L2)
(3&9 to L3) (4,5,6,10,11,12 tied together and to neutral tap).
I believe to get 277/480 i need to rewire as follows:(1 to L1)
(2 to L2) (3 to L3) (4&7 together) (5&6 together) (6&9 together)
(10,11,12 together and to neutral tap).I think i am on the right track, any suggestions?
(3&9 to L3) (4,5,6,10,11,12 tied together and to neutral tap).
I believe to get 277/480 i need to rewire as follows:(1 to L1)
(2 to L2) (3 to L3) (4&7 together) (5&6 together) (6&9 together)
(10,11,12 together and to neutral tap).I think i am on the right track, any suggestions?





RE: 50kw diesel generator 12 lead, from 120/208 to 277/480
RE: 50kw diesel generator 12 lead, from 120/208 to 277/480
You may/most likely also need to configure the voltage regulator/exciter supply/reference voltage sources for the higher voltage! Just depends on the design of the generator controls.
Be very cautious, magic smoke is expensive to replace!
RE: 50kw diesel generator 12 lead, from 120/208 to 277/480
So, the generator would have to run at 115% of the present output voltage to produce 277/480V. The generator might be capable of this but the manufacturer should be consulted. Besides, as already pointed out, you'll likely have to scrounge up some documents to figure out how to reconnect the regulator and possibly change or reconnect some other parts in the unit due to the output voltage change.
RE: 50kw diesel generator 12 lead, from 120/208 to 277/480
CAUTION: Be sure that the AVR sense leads are still connected to 240 Volts. That will be tapped off your 4-7 and 5-8 connections. (and 6-9 if three phase sensing is used).
If the AVR is self powered the power leads must be connected to 240 Volts (4-7, 5-8, and 6-9). If the set is equipped with a Permanent Magnet Generator that will power the AVR with no change in power connections.
Bill
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"Why not the best?"
Jimmy Carter
RE: 50kw diesel generator 12 lead, from 120/208 to 277/480