Problem Inverter question

[lostinfla]

While on the way to our short trip (about 170 miles one way) destination, the wife went to the refrigerator to get some tea for me, and she said "the light's off". Stopped at a rest area and saw the Magnum panel had a fault which I believe said "FET overload". I reset the inverter with the power button and it acted normal again. Now, when we got back home the fridge was off again and the inverter panel had a fault marked "internal NTC." I reset it again and it's back to normal for now. I didn't have any extreme load on the system when this happened. Any ideas as to what's happening would be appreciated.

 

[Richpatty]

This is what the rectangle of knowledge found…. Hope it helps. Keep us posted.

Looks like a temp issue….or the inverter is on the fritz…

Fault Code Troubleshooting for ME-RC, ME-MR, ME-ARC, and ME-ARTR Remotes | Magnum Dimensions

Fault code troubleshooting guide for Magnum Energy ME-RC, ME-MR, ME-ARC, and ME-ARTR remotes.

www.magnum-dimensions.com

 

[lostinfla]

Thanks Rich, I did see that. I'm trying to avoid the "take it to an authorized service center" part as the nearest one, according to their website, is over 800 miles away.

 

[Richpatty]

I figured you might have searched…maybe the inverter has collected a lot of dust? Or the cooling fans are not working well?

 

[lostinfla]

That's a good idea, I'll check it out.

 

[Neal]

I have a Magnum 2812 I could sell if needed, it's just a heavy monster. I use Victron inverters now and didn't want to leave it with SES on consignment. But if someone needs a spare 2812 I have one.

 

[lostinfla]

I have a Magnum 2812 I could sell if needed, it's just a heavy monster. I use Victron inverters now and didn't want to leave it with SES on consignment. But if someone needs a spare 2812 I have one.

I may be needing it. Thx

 

[Kevin D Pem]

I wouldn't replace the inverter yet! My search would be a loose connection on the fridge circuit.

The inverter safety features seem to be working as designed.

I'll explain.

The FET (field effect transistors) is being overloaded. This shows up as a general overload.

Further down the road rather than shut the inverter down, those overloaded transistors heated up the heatsink they are mounted to.

What can make the transistors overheat, or overload? Well a fridge that has been interrupted on a cycle, then immediately trying to restart it before the head pressure has had time to equalize. . The result is a locked rotor condition of the compressor motor. That can be 10 times the run current, so overload of the inverter is likely.

My assumption is this only happens while on the road, so bad connection is the conclusion.

 

[Jim]

I'm inclined to go along with Kevin. I had something similar last year and it turned out to be a bad ground. Check the battery compartment and you'll see where the neg side of the battery bank grounds to the coach. I believe the inverter is also grounded to that same spot. Mine was finger tight, or finger loose, however you want to view it. No idea how it got so loose, but it was. Tightened it up and haven't had a problem since.

 

[MarkMaxPayne]

One thing I added to my rig to find out immediately when the fridge loses power was this power failure / GFCI trip detector from Amazon. I had a trip where I was on the inverters and they shut down due to low house batteries and I didn't realize this until after we were parked at our destination. Had I known I would have fired up the generator while driving. My 120VAC fridge is powered off of the same circuit as the GFCI plug that is in the bathroom. I plugged this into that GFCI plug and any time it trips or loses power, this alarm goes off: Power Failure Alarm

When in storage and have things turned off, I just unplug the device, hit the play/pause button, and place it in the bowl of the bathroom sink that is right above the GFCI outlet.

Best,
-Mark

 

[PdMeehan]

@lostinfla I had some problems with my inverter and called magnum at 425-353-8833. A service tech called me to setup an appointment over the phone. When he called back he walked me through various troubleshooting steps such as soft and hard resets, etc. I was very impressed. unfortunately, for me, I had to replace my inverter.
The removal and installation was performed at Independence RV in Winter Garden. I believe you are in Tampa they are about 90 miles from you. Way better than 800 miles.
Best of luck!

 

[AbdRahim]

How does this work? Doesn’t the inverter keep the fridge on when external A/C is lost? I could use an alarm for that.

 

[lostinfla]

I've called Magnum and can't get to a person. I get a message: "all tech support people are busy, call back later." Checked the grounds from the battery bank to the frame and on the inverter itself, and they all seem to be tight. I really don't hear fans or feel any air coming from the unit. Wondering if the fans could be the culprit. I'm going to pull the cover off the inverter and try to see if they are free or stuck. I seem to remember hearing fan sound previously. Maybe I'm mistaken.

 

[Kevin D Pem]

I've called Magnum and can't get to a person. I get a message: "all tech support people are busy, call back later." Checked the grounds from the battery bank to the frame and on the inverter itself, and they all seem to be tight. I really don't hear fans or feel any air coming from the unit. Wondering if the fans could be the culprit. I'm going to pull the cover off the inverter and try to see if they are free or stuck. I seem to remember hearing fan sound previously. Maybe I'm mistaken.

Is the problem still there? Have the fans been making more noise lately?

 

[lostinfla]

Is the problem still there? Have the fans been making more noise lately?

I'm not going to pull it apart for a few days yet as I'm still moving back into the house from the coach. I really can't hear any sounds like fans from the unit and feel no air moving in or out of the vents. I've got the inverter turned off (charger still on) and plugged in at home (50a) to get power. I'll report when I know more.

 

[Kevin D Pem]

The fan should only run with a fair load.

 

[lostinfla]

After consulting with a repair tech and trying a few tests, it seems as if the inverter has given up the ghost. Now it won't even pass power to the coach. To simplify installation, I ordered another Magnum ($$$). At least the new one is compatible with Lithium for the next battery change out. Now, to try to get the old one out is my next adventure....

 

[Richpatty]

Thanks for the update….same model?

 

[lostinfla]

MS2812-L-U. Newer model that will work with Lithium, or so I'm told.

 

[GlampDaddy]

After consulting with a repair tech and trying a few tests, it seems as if the inverter has given up the ghost. Now it won't even pass power to the coach. To simplify installation, I ordered another Magnum ($$$). At least the new one is compatible with Lithium for the next battery change out. Now, to try to get the old one out is my next adventure....

Let me know if you want help.