2011 MEP 804B fuse/resister MOV mod ?

[primuss]

Sorry for asking this but my head is swimming about this.

I have a 2011 804B with 39 hours from Fremont with a TRC regulator. There is a fuse installed on the left side but do I need to put the MOV too? I've read so many posts and TM's I'm confusing myself at this point. Most of the threads are on slightly older sets so I don't know if the problem was fixed by the time this one was made. I'm almost ready to fire it up and don't want to cook something because I didn't pay attention.

 

[Light in the Dark]

The MOV is an up-and-above addition to the quad fuse modification. Unfortunately I don't have an answer on your particular machine, but know on the smaller sets, the MOV is just extra insurance (where the quad mod is a must in my eyes).

 

[primuss]

Ahh...thank you for the info. I like extra insurance, gives me a fuzzy feeling. Maybe someone will chime in with thoughts on my particular machine.

 

[kloppk]

The "MOV mod" is not in any TM. It's a modification I suggested a few years back to be added to MEP-802A's and MEP-803A's.
It's intent is to prevent voltage spikes from the their Quad Windings from damaging the Voltage Regulator.

The "Fuse Mod" only protects the gen head from damage but does nothing to protect the voltage regulator from being damaged.

 

[primuss]

Would the same apply to a 804B then? Or is it not affected the same way the other models are? Or unknown right now? I'm just going off of reading on here and seeing the fuse and holder on the left side of the regulator, so it looks like half the problem was addressed by the factory by 2011.

I do have a 802A I got at the same time as the 804B, I just haven't started playing with it yet. I will keep this bookmarked so I remember to look and see on it.

 

[Guyfang]

Would the same apply to a 804B then? (YES!!) Or is it not affected the same way the other models are? (NO!) Or unknown right now? I'm just going off of reading on here and seeing the fuse and holder on the left side of the regulator, so it looks like half the problem was addressed by the factory by 2011.

I do have a 802A I got at the same time as the 804B, I just haven't started playing with it yet. I will keep this bookmarked so I remember to look and see on it.

The Quad Mod is a must. I would also say the same for the MOV mod.

The only TQG gen sets that do not need the Quad mod are the 30 and 60 KW TQGS, that use a CIM, (computer screen) in them. The same for the MOV mod.

 

[robertsears1]

When you go to start your generators, you must keep the switch in start for around 5-10 seconds After it is running. It will not hurt anything and it gets the oil press up and energizes the field so it will produce electricity. Did you get the 804b to power three phase equipment? Unlike the 802 which is selectable,it only makes 3 phase power. At 208 or 416V. There are ways to get some single phase out of it but it was not designed for that. An 804 is not a good fit for most homes.

 

[primuss]

Guyfang, thanks for the input. May I ask where the MOV should go on the 804B? I have a voltage regulator but I don't find anything labeled "quad" like the first picture of someone's 803. I've attached pics of my TRC voltage regulator and then what the TM calls a diesel engine governor. (TM 9-6115-643-24P)

robertsears1, I will definitely make sure to hold the switch on start up, that is field clearing if I remember my reading right. I got the 804B and the 802A because I could. I knew the 804B was not ideal for home use, but I wasn't going to pass it up and I'll work within it's limitations. I don't have any need for 3ph but it might come in handy at some point. I have a whole home commercial propane unit for my house, and I just sold a 802a I had picked up but never messed with because I bought it for the trailer it was on. I inherited a MEP-016D I'm playing with right now alongside the 804B, so all in all, I'm happier than a puppy with two peters. I leave the office and rush home so I can listen to the missus complain about fuel tanks in the sink and why do I smell like diesel all the time now.

 

[kloppk]

You'll need to use a different MOV than the one used on the 802's and 803's due to the higher voltage that the TRC Voltage Regulator is powered by.
The 802/803 VR gets powered by ~ 60 VAC whereas the TRC 804's regulator is powered with ~ 155 VAC.
I'd recommend something like a MOV-20D241K
It would get installed across the voltage regulator terminals 10 & 11.

 

[primuss]

Awesome kloppk, thank you very much for sharing your knowledge.

Just for future people looking for MEP-804B MOV mod info I've attached a picture of the 802/803 mods and the 804B mod. Hopefully I got it right.

I saw that terminals 10/11 were addressed here, but never confirmed. https://www.steelsoldiers.com/threa...voltage-regulation-issues.197486/post-2303651