MEP-831A Inverters

[Light in the Dark]

I've seen so many sets come up missing this piece. Whats the deal... poor reliability on the part (so constant scavenging)? Any availability on the secondary market?

 

[DieselAddict]

Based on my experience they are being grabbed due to failure.

I suspect the conformal coating is failing on the boards and they start suffering from moisture related issues. I have a few 831s that I plan to swap parts around and make a couple of runners. I want to dig into the inverter at some point and see what I can figure out.

 

[Demoh]

Wondering the same. one of my on-hold projects is repair of a bad inverter that does produce voltage, just way too high.

I have a thread with some of my findings back when I only had 1 831, but since I have 3 now and at least 1 working inverter I have this project on hold.

thread: https://www.steelsoldiers.com/showt...ody-have-luck-with-repairing-these&highlight=

For this thread I am wondering what the failure mode is for the majority of the ones out there.

 

[USAMilRet]

I don't have one. Although I suspect and believe that DA hit it on the head. I have seen a lot of inverters die due to moisture invasion once the sealing has begun to break down. I have also seen these things go because of the caps degrading and no longer being able to do their jobs.

 

[Light in the Dark]

Would be great if someone could engineer a workaround for these sets. I doubt I will ever own one, but certainly there were enough fielded that there is real demand for a fix here. Good job SS peeps.

 

[DieselAddict]

Wondering the same. one of my on-hold projects is repair of a bad inverter that does produce voltage, just way too high.

I have a thread with some of my findings back when I only had 1 831, but since I have 3 now and at least 1 working inverter I have this project on hold.

thread: https://www.steelsoldiers.com/showt...ody-have-luck-with-repairing-these&highlight=

For this thread I am wondering what the failure mode is for the majority of the ones out there.

Hopefully I can help out on that thread at some point when I have time and space to work on it.

 

[profo]

I thought it through and I am going to just buy a gen head from northern tool that will fit into the same enclosure I measured it and it will work, all you do and remove the governor assembly and inverter and just run it with the built engine governor at 3600 rpm in reality it only changes a few hundred rpm the way its setup now, will keep yall posted on progress but it is just pretty straight forward! You would remove the PMG (alternator on side of engine and directly bolt gen head onto engine its about 300 bucks and bolts directly onto the yanmar engine and is small enough to fit into the MEP831 enclousure, it is a four wire generator so it can be wired for 120 only or option of 120/240 but this may cause problems with the other controls. Everything stays the same and you will not have to deal with inverter or governor assembly anymore. Only problem I see is shutting it down but I found some injector pumps off E*** for about 80 bucks that have a electric solenoid built in which could be tied into the low oil/overheat circuit.

Marty

 

[pjwest03]

A lot of things manufactured in the 99-07 time frame suffer from the capacitor plague.

Some background: https://en.wikipedia.org/wiki/Capacitor_plague

 

[Cptn Cornelius]

I thought it through and I am going to just buy a gen head from northern tool that will fit into the same enclosure I measured it and it will work, all you do and remove the governor assembly and inverter and just run it with the built engine governor at 3600 rpm in reality it only changes a few hundred rpm the way its setup now, will keep yall posted on progress but it is just pretty straight forward! You would remove the PMG (alternator on side of engine and directly bolt gen head onto engine its about 300 bucks and bolts directly onto the yanmar engine and is small enough to fit into the MEP831 enclousure, it is a four wire generator so it can be wired for 120 only or option of 120/240 but this may cause problems with the other controls. Everything stays the same and you will not have to deal with inverter or governor assembly anymore. Only problem I see is shutting it down but I found some injector pumps off E*** for about 80 bucks that have a electric solenoid built in which could be tied into the low oil/overheat circuit.

Marty

Did you have any luck mounting the generator? Run into any issue? I was thinking of doing the same thing.

 

[kloppk]

Unfortunately Northern Tool hasn't carried that gen head for a few years.
Yes, the Northern Tool gen head does fit on the Yanmar in the 831A. I have one on an 831 in my garage. Pic below.
The equivalent gen head can be purchased from Mecc Alt. I've bought a few of them from them the last couple of years to do conversions.

FYI - I produce conversions kits to do the swap which includes a custom governor controller to maintain 60 Hz, current sensors for overload protection and a transformer assembly to restore battery charger operation and all needed hardware.

 

[Cptn Cornelius]

Looks great, @kloppk. I think I have a 1659201 generator head somewhere (maybe), I'll have to dig around for it. Not sure if this old 831AE is worth the cost or trouble if I have to go hunting a used generator head down though. If I can find it I'd be interested in your kit for sure, what would that run me?

 

[kloppk]

Looks great, @kloppk. I think I have a 1659201 generator head somewhere (maybe), I'll have to dig around for it. Not sure if this old 831AE is worth the cost or trouble if I have to go hunting a used generator head down though. If I can find it I'd be interested in your kit for sure, what would that run me?

I'll send you a PM

 

[Light in the Dark]

I bought a 2.5KW tapered head years ago, to convert over an MEP-501. I believe the engine in that has the same taper as the L70? Its still new in box, would be happy to discuss with you by PM if interested.

 

[kloppk]

The MEP-831 uses the J609B configuration for mating to the gen head.

 

[Light in the Dark]

Yeah pretty certain I verified it was the 609B taper on this one too. If @ Cptn Cornelius I am sure we can discuss.

 

[Cptn Cornelius]

Had a busy schedule here lately and just getting back to this, thank you guys for the info. Still not sure If I want to go through the trouble converting this thing and haven't had a chance to look for that generator head. It's not high on the priority list right now anyway, just keeps nagging at me every time I look at it.

I can't keep from overloading the projects on myself so I'm sure the conversion is inevitable...

 

[DD58]

I have 1 known bad inverter and 1 suspected.
I did Kloppk conversion kit and am more then happy with how it performs now. I’m keeping my eyes on this thread to see if I can fix the one inverter.


Sent from my iPhone using Tapatalk

 

[mullet1971]

Unfortunately Northern Tool hasn't carried that gen head for a few years.
Yes, the Northern Tool gen head does fit on the Yanmar in the 831A. I have one on an 831 in my garage. Pic below.
The equivalent gen head can be purchased from Mecc Alt. I've bought a few of them from them the last couple of years to do conversions.

FYI - I produce conversions kits to do the swap which includes a custom governor controller to maintain 60 Hz, current sensors for overload protection and a transformer assembly to restore battery charger operation and all needed hardware.

View attachment 919456

I would like some more information about the conversion kits you sell please.

 

[DD58]

I would like some more information about the conversion kits you sell please.

Here’s my post on doing my conversion.

www.steelsoldiers.com/index.php?threads/Mep831a-conversion-time%21%21.216104/&share_type=t&link_source=app


Sent from my iPhone using Tapatalk

 

[kloppk]

I would like some more information about the conversion kits you sell please.

The conversion involves removing the inverter, PMA and SLC100 Governor Controller module.
Relocating the J7 connector to make room for the gen head
Installing the new gen head and installing the conversion kit.

The kit includes:
New Governor Controller module to maintain 3,600 RPM for 60 Hz.
Transformer assembly to restore battery charger operation
Current Transformers and wire harness to sense gen head output currents
Wire harness to restore contactor operation, AC Voltmeter operation, Load Meter operation, Overload Fault Detection and Short Circuit detection.
All hardware needed for the conversion
Detailed step by step printed instructions on how to remove the PMA, Inverter and relocate J7.
Detailed step by step printed instructions on how to install the new gen head and install the balance of the conversion kit.

The gen head is NOT provided in the kit. I can provide the contact info for ordering the gen head directly from Mecc Alt here in the US. The gen head is a 4.2 KVA gen head and the cost shipped directly to you is about $400-$450. Mecc Alt ships them out quickly. I usually get them in 2-3 days.

The Conversion kit is $350 and includes USPS Priority shipping.

I can provide you PDF's of the conversion process. Just PM me your email address and I'll zip them off to you.

Kurt