Inverter shutdown

[ditto]

Operating microwave on inverter power, inverter shuts down with message "low battery" and red fault light on. Now that microwave is off, inverter comes back online 12.4 volt showing. Batteries fully charged after 5plus hours on road. Batteries tested and show good. Tested the Samsung microwave , drawing less than 15 amps at shut down. Any suggestions?

[TXBart]

I was told you couldn't run the microwave on battery. We always start the gen to zap lunch.


Vance & Robin
Dexter and Winston - Old English Sheepdog Security Service
2014 Entegra Anthem 42DEQ

[pasdad1]

How long was the microwave on? Sounds like the batteries are low.

[hawgguy]

Originally Posted by TXBart

I was told you couldn't run the microwave on battery. We always start the gen to zap lunch.

I do all the time, admittedly for short 1-2 minute intervals.

[ditto]

I have confirmed it should run on the inverter. Usually shuts down after 1 minute. Batteries were fully charged and have been tested as well. Thanks for your comments too!

[derba]

Your house batteries are toast. No Reserve capacity. The are volts with no load, as soon as you draw amps out of them, the volts go down below the low cutoff for the inverter.

Your house batteries need to be replaced.

Sorry.

[Nana25K]

We had the same issue following the recent installation of a new invertor. We are sure that our house batteries are probable gone and will be having them checked next week.
Our confirming clue was that while we were dry camping and this happened our gas furnace also didn't work. Plugged into shore power and it works just fine.
So yes a low voltage issue
Now of course it also pays to check out wiring etc.

[twinboat]

Before you toss your batteries, what length and gauge cables are you using for the inverter.

If too long or thin, the battery power will not get to the inverter.

We don't have a generator waiting to go, so we run our microwave on our 2000 watt inverter anytime we need it.

We are using 00 gauge cable and run them 3 feet from the batteries.

[ditto]

Load test done on all batteries, checked out good!

[pasdad1]

Originally Posted by ditto

Load test done on all batteries, checked out good!

Then it's also possible the battery charge profile is set incorrectly, and your batteries are not getting fully charged.

Do you have AGM or flooded batteries? How many?

[nothermark]

You could also be dealing with battery age issues. As the batteries age the internal resistance increases so the internal drop goes up and the supplied voltage under load goes down. At some point the load of your inverter feeding the microwave will result in a large enough internal battery drop to indicate a low line condition. Given the powers involved I would expect that to happen well before we considered the batteries were toast.

[jrusselltx]

The 15 Amps at shutdown (assuming you are talking at the 12 Volt battery) is nowhere near the power the microwave is pulling from the inverter. A micrwowave oven will pull anywhere from 700 to 1200 Watts when it is generating microwave energy. Translated (roughly) to the 12 volt battery, that is 65 to 111 Amps from the batteries. You don't say how you tested the batteries or why they "show good" so conclusions are hard to draw. If it worked before, then either there is a loose/corroded connection, or the batteries aren't really good. If it never worked, it's harder to say, but it's a heavy load on the batteries which will drop their voltage way down.

[hawgguy]

2016 coach with 8 AGM batteries - I wonder if it's something else entirely.

[ditto]

Thanks Bob,yes, this is a 2016 Anthem, built in December, 2015. Tech did the battery testing,and monitoring of microwave draw , all is within specs. Waiting for Magnum to respond back to us with an action plan.

Again, thank you all for your suggestions! I posted to determine if anyone has had a similar issue.