I have an MEP-805B which I am planning to use to drive some 480V loads. Based on my understanding of TM 9-6115-671-14, table 1-2 on page 1-15, it is possible to get three distinct phases of 480V by setting the mode to 240/416V nominal, then cranking up the voltage regulator until it hits 480V. Is this correct?
Assuming it is, then I have another problem. I basically only have two 480V loads, and they aren't equal—not sure exactly, but something like 10 kW and 8 kW. So the three phases would be differentially laden: 10 kW, 8 kW, and 0 kW. My concern is that such extreme imbalance will somehow damage the generator head, perhaps by making it shake or putting sideways force on the bearings.
I cannot find any guidance in the TM about how important it is to balance load among the phases. What are people's thoughts here?
What part of this am i missing, WHY do both of the 480 loads have to be one one set of output phases, ie. it seems to my reading in your example, you are for discussion, going to use L1 and L2 for BOTH loads.. Why not use the one load between phases's 1-2 and the second load between phases's 2-3 that's plenty close enuff of balancing to settle any discussion IMO..
Now the voltage output level is a whole nother discussion. as has been cautioned your not likely to get 480 in just panel voltage pot adjustment and if you do it will be spotty and in my experience more nuisance faults than its worth.. In my career of electrical contracting your equipment will not suffer in the least being supplied by 460 volts, but if you're just that determined then go ahead, and further and personally would not be concerned to move into the 450 range [run your equipment and check for expected performances to be the deciding point] and then your internals of the set will function without all the nuisance fault issues.
BUT ? i live closer to the edge so i dont take up more room for others that want it.
your actual generator will perform well at 480 with no issues, its the alerts,warnings and fault set points that will be the pain in the ass to reset to accept the higher voltages, the actual regulator will respond to being adjusted to the higher range, , the OV relay sensing and the one potential transformer will come into consideration also. most of this nonsense can be well resolved, its just you're patience level or support help that will finally determine your success ... im working from memory with all this and too lazy to go dig out the manual and wiring schematic, but the convenience outlet should remain at 120 from where its picked off from, and this might carry to the potential xformer in the upper right side above the load board, but in my head im pretty sure it is sensing is from what now is the 240 voltage and increasing it to 265/277 can present issues, this might be solved easily, i just need to review the manual to be sure. to wrap this blab up, it will work, just a learning experience for you.
lets know or keep us informed.. mac/mc
