Converting a MEP-831A to standard generator

[OverkillTASF]

I don't know where I left off... but I got the NorthStar 4000 watt generator head installed and the whole assembly shoved back in.

I did have to move over the big main round connector and still have yet to remount the contactor.

Complications in my case have been needing to rebuild the pigtail for the generator head since I lost mine... and I am missing the nuts for the output terminals without an easy replacement..

Here are the wires coming from the generator head, with their crappy ferules installed. I was surprised that the wire coming from the head was 14 AWG given that the generator might handle 33 amps. But I guess if all is going well, that load will be split over each winding so 16.5 amps each:


These will run to this terminal strip installed on the back wall of the enclosure so I can easily rewire for 120/240 operation.

 

[kloppk]

I'd just chop those ferules off and extend the wires as needed with suitable wire and some crimp butt connectors.

For mounting the contactor I suggest doing this. Re-use the "L" bracket that was used under the inverter and do this.
Just need to drill 1 hole to mount the contactor to it.

 

[OverkillTASF]

For mounting the contactor I suggest doing this. Re-use the "L" bracket that was used under the inverter and do this.
Just need to drill 1 hole to mount the contactor to it.

I like that... I'm not sure how easily I can get to that spot now but I'll give it a look. Certainly worth reusing that L bracket!

 

[kloppk]

By popular demand kits are again available to perform the Gen Head Swap on MEP-831A's!
Gen Head Swap Kit

 

[kloppk]

Two kits remaining & ready to ship.
Those are the last two available.

 

[OverkillTASF]

@kloppk

Got the contactor mounted and the new governor board installed. Ran the generator the "dumb" way last night. Want to finish this install!

- I can't reach TB6. I had the engine reinstalled before I got the kit. It looks like you want to connect the supplied white J17 harness to TB6 where the three... A1, B1, C1 windings of PMA were. These are sense wires based on the size... And I think the terminal block basically connects the PMA voltage (top row) to the governor's voltage sense (bottom row). With the PMA missing... The voltage reading will come from... Somewhere upstream of P17. Eh I can't figure it out since I cant see how the supplied J17 is wired. What can I do about not being able to reach TB6? I really don't want to have to mess around with the exhaust again...
- Regarding the current sensor donuts... I have my generator head windings pulled out to a terminal block. Currently configured for 120 volts, but do need to change on demand to 120/240. I can't quite grock the directions for the current sensors... Do you have a wiring diagram showing how to do the current sensors for 120 and 120/240 operation?

 

[kloppk]

I hear you about the exhaust!

For TB6 you could cut the 3 factory wire harness wires as close to TB6 as possible and then splice them to my wire harness 3 wires for TB6.
Splice....
My TB6-1 wire to factory wire 115B16
My TB6-2 wire to factory wire 116B16
My TB6-3 wire to factory wire 117B16

With the conversion TB6-1 is L1 from the gen head
With the conversion TB6-2 is L2 from the gen head
With the conversion TB6-3 is my signal from the Governor Controller board that drives the Load Meter.

My donut current sensors would be installed on the L1 and L2 leads as they exit the gen head and before any connections to create 120 or 120/240.
Are you going to use a switch to accomplish the 120 to 120/240 mode change? I've done it with heavy duty 4PDT toggle switch on a conversion I did a few years back.

After the conversion the Load meter will display the current on the gen head leg with the greatest current.

 

[OverkillTASF]

Thanks, I think this should get me covered.

When you say L1 and L2... You mean whatever I'm using as "hot" from the head right?

 

[kloppk]

Correct, the two "hot" leads from the gen head.