MMS1012 shuts off when hooked to generator

cralls

Hi All,

Wondering if anyone has any ideas on this.. I have an MMS1012 that shuts off when it's plugged into my generator after about 45 minutes or so and won't come back on for about 10 minutes. It only happens when plugged into the generator. Both times it happened I had about 200 to 300 watts of load on the inverter and since it has a PCF charger it was charging a 12v 464ah bank at the same time.

cralls

Hi All,

So just to help a bit more I've put together a wiring diagram here... perhaps there is an issue with my wiring but the issue has only shown up on generator power so far. Happy to hear any critiques of my system here as well.

vtmaps

cralls said:

Both times it happened I had about 200 to 300 watts of load on the inverter and since it has a PCF charger it was charging a 12v 464ah bank at the same time.

That magnum is an inverter/charger, but only one at a time.  When you run the generator, your 200 to 300 watt load is powered by the generator, not the inverter.

cralls said:

I have an MMS1012 that shuts off when it's plugged into my generator after about 45 minutes or so and won't come back on for about 10 minutes.

What, exactly happens... does it stop charging the battery?  What about the loads... do they still get power from the generator?

--vtMaps

cralls

Hi vtmaps,

Thanks for the response. You are correct, it is only inverting or charging but not both so in this instance it's charging and passing the load through to the generator.

When the inverter shuts off all activity stops. The loads all die and charging to the battery stops. Nothing I do will bring it back to life including opening the disconnect between the battery bank, disconnecting the generator, or holding the button on the inverter down to reset the inverter. I just have to wait about 5-10 minutes or so and then it comes back alive. It almost seems like a thermal fuse is blowing but I don't know that it has one? Also, not sure why it would get hot.. the ambient temperature is around 70 around the inverter and it doesn't feel hot to the touch... just warm but I would think that would be ok.

vtmaps

What generator are you using... is it putting out clean power under the combined loads (battery charging and other loads)? 

This has only happened twice?  What was the battery voltage at the time?  Did it occur during daytime while the panels were making power?

--vtMaps

cralls

Hi vtMaps,

Great questions... I'm using a Champion 3500w generator model 46596. Not sure how clean the power is from it or how I would figure that out but that's a great question to start debugging my issue here. 

This has happened 3 times now. The battery voltage at the time measured 13.4 (this was while the inverter was charging the batteries of course so I'm not sure what the actual voltage of the bank was. This has occurred both at night as well as day time. It also happened before I even had the panels and charge controller installed so at that time the only components were the battery bank, inverter and generator.

I would also note that at the time it happened the generator throttled down for a second and back up so I'm not sure if that was due to the load drop on the generator or if it was actually having an issue itself. I've only run the generator an estimated 60 hours since it was new and prior to having the inverter/battery bank setup I would plug it directly into the camper and never had any issues but that doesn't necessarily mean one hasn't developed I suppose. The inverter doesn't have this issue on shore power or solar power so the problem certainly could be a hiccup in the generator but that wouldn't explain why the inverter won't come back on for about 5-10 minutes even after everything being disconnected and re-connected.

Vic

Hi cralls,

This does sound  like a thermal issue.   Wonder what was the charge current at the time of shutdown.

Believe that this inverter/charger does have a variable-speed thermally controlled fan ...  had wondered if,  perhaps that the fan is not running,  the air flow is blocked,  of perhaps the ambient temps where the inverter is located is high,  and so on?

Vic

cralls

Hi Vic,

That gives me a troubleshooting path at least... I'll see if I can figure out what the charge current is at the time of shutdown. This means I need to order the remote for the inverter which I've wanted to do anyway so now I have an excuse

It's hard for me to hear the fan over the noise of the generator outside but I will definitely check this and make sure it's coming on. The charge controller and inverter are right next to each other and I definitely hear the fan on the charge controller but not sure about the inverter... I'll have to double check that. If this were the case it would make me wonder why it will run for several hours after this happens once the inverter comes back up. It seems that it happens after about 45 minutes... the inverter stays down for about 5-10 minutes... and then once it's back up I run off the generator for several more hours w/o issues. If it were a fan/temp issue I would expect it to continually happen no?

If you guys happen to think of any other troubleshooting paths in addition to what you've already mentioned (thank you!) let me know and I'll try those too. I just want to make sure there's nothing wrong with the inverter before my warranty period is over. I think I have about 2 months left on that.

Vic

Hi again cralls,

Often one can detect air flow,  by wetting the back of one's hand and placing it near the outlet of a device that has a fan.

Regarding the charge current from the inverter,  really wanted to know the integrated (total) charge current from the start of battery charging to the point of shutdown,  but this is a bit too difficult for most of us to determine.

Battery charging can be a long slog,  and the bulk (really the Bulk)  of the charging occurs in the first 60 or so percent of the charge session,  at least for charger output current (unless the charger is always stuck in its maximum limit).

Yes,  if you had the remote,  it might indicate some Fault condition that would be informative,  and might allow you to set some important charge parameters,  etc.

Vic