MEP-006A Voltage Questions

[Brandon314159]

I have a couple questions regarding a new-to-me MEP006.

1) I see the voltage selection card on the left side of the set, however I am not sure how you are supposed to 'move' this...does it slide? Do I remove all the nuts and then bolt it all back on at the next point up? I see the arrows, but I don't want to force this and break anything.

2) For the application that I am using this set for, it would be VERY advantageous to have 480 3-phase (I believe wye, not delta - industrial power)...the generator head is capable of the 480 although the set indicates it can only do a maximum of 416 3-phase. What are the limitations here? Will the exciting circuit allow me to just crank it up to 480 and rock and roll? I presume it will over-voltage cutout, but since I can't move the card yet, I cannot experiment.

If anyone is thinking of mirroring the big generator, small load, wet stacking issue...I have two 100HP electric motors to run and a 30kW 480V 3-phase electric room heater if I need it. Creating a load is NOT an issue.

Thanks for the help!

 

[Speddmon]

As to the card, you unbolt it completely and move it up and re-bolt it.

Now to your voltage question. Those sets and all military 3 phase sets are set up in a "wye" configuration. 208 and 416 volts are "wye" voltages. Your set, as is, cannot achieve 480 volts 3 phase "delta". It would require a complete re-wire of the output connections. Can it be done? Probably. The connections of a 12 lead generator head can be reconnected in just about any way you want them done. Will the generator work properly after you reconnect the leads? This I have no idea. The generator was designed and build to produce those specific voltages. The metering, safety monitoring and voltage regulation were all designed around 208, 416 volts. I have no idea how you set would react when you start messing with the connections.

 

[Isaac-1]

Let me first say I have only the most basic of knowledge about the MEP-006, I skim over the TM a couple of years ago. Having said that if you need 277/480 Wye for a specific need there are a couple of ways of getting there.

1, The generator connection for a 12 lead unit for 240/416 wye and 277/480 wye are the same, it is just a control and voltage regulation issue, if the built in system can't be adjusted that high, there is always the option of replacing it with an after market voltage regulator and tricking any safeties with a step down transformer.

2, Another option is to generate either 120/208 wye or 240/416 wye and step it up to 277/480 with a transformer (note transformers are bi-directonal devices this means you can run a 277/480 to 120/208 step down transformer in reverse to get get 277/480, many of these transformers have fine tuning taps to get to specific output which only work one way, however the high side output voltage can be fine tuned by adjusting the input voltage instead of tap position.

Ike

p.s. I doubt that a MEP-006 can start a 100 hp motor

 

[steelandcanvas]

p.s. I doubt that a MEP-006 can start a 100 hp motor

 

[Brandon314159]

Update:

Generator is working flawlessly at the de-construction site. Running various electric motors, lighting, transformers, etc. I scored a 30kW heater and a 10kW heater (480V) so I use those as load banks periodically if the load is not enough to make the generator work a little hard.

FYI, the over-voltage shutdown will not activate until about 470-475V so the MEP006 can actually run the 480V equipment, just set it on the edge and park it.

I never did determine if the buildings were delta or wye, however there is a mix of both (and some transformers mixing them throughout the site). Now to score a few transformers for myself

Thanks for the help!