Mep-805a

[MtnSnow]

The trick when converting a 3 phase Gen to "single" phase 120/208 is to load the two 120v feeds as evenly a possible since it is now wired in zig-zag from the Wye configuration.

 

[Ratch]

Ha, I thought the spare was the rear tire of the vehicle on the ground...
Nice Jeep, too!

 

[RobGlass]

The trick when converting a 3 phase Gen to "single" phase 120/208 is to load the two 120v feeds as evenly a possible since it is now wired in zig-zag from the Wye configuration.
View attachment 523078

While I am in no way an expert on this stuff I have learned quite a lot from this guy on Youtube:
sewerzukThis was his response to another on your same concern:




"It isn't a problem as long as you don't exceed the current limits for a single leg (this is why you're limited to about 2/3 of rated power). The tech manual even says that pulling single phase power is permissible, provided the current limits aren't exceeded. I've heard the "uneven heating" and "unbalanced load" myths too. These generators are designed to work this way! Other generators' instrumentation, control, protection, and excitation systems may not allow single phase operation; but with the MEP's it is just fine."



 

[MtnSnow]

Can you load up the Gen on just a single leg and have it work...**** yeah but it won't enjoy it and in time you will incur downtime because of it. Run it as you see fit but for longevity balance the loads. (While I don't claim to know it all and I will never know it all, I work work with Diesel generators almost daily in my day job managing Data Centers ranging from 300KW to multiple 1MW paralleled units)

 

[m-35tom]

i don't see how this information can be correct. the 805 is a 10 wire, 3 phase ONLY generator. it cannot be wired in the common ziz-zag that 12 wire machines can. there have been quite a few posts in the past few years about the 805, everyone hopes it can be made single phase, it cannot. the best you can do is 120/208 from four of the 6 windings and have just 20 kw for your house. it will seem like single phase but the phase relationship is 120°, not 180°

 

[tim292stro]

Quick Google provided this: http://www.steelsoldiers.com/showthread.php?130403-MEP-805a-reconfigure-to-single-phase

Before you get excited about the thread title the summary is "no". You might need to look into 3-phase to 1-phase converters (though I'll admit I've never heard of anyone doing that way). I'm guessing you miught have better luck replacing the generator head, or just "becoming one" with the idea of using three phase...

 

[tim292stro]

Without knowing if it can be done to code, I'd say maybe look into a variable frequency drive (essentially an inverter)? Though again, I've not seen a 40HP version that does single phase...

 

[m-35tom]

yes there are ways to use it, but again, the question is often asked and there are many of these being auctioned off. it is 3 phase ONLY. also consider that each of the 3 windings in the head are in series and cannot be paralled. this is how it has 2 voltages, the neutral end of one winding to center tap is 120 volt and to high end of winding is 240 volt. from any center tap to another tap is 208 volts. from any 2 high ends is 416 volt.