I want to run a microwave on an inverter

[zzyzxpat]

I have an AF 865 camper. I want to be able to run the microwave, 900W, power demand shown to be 1350W, on an inverter for a short period of time, just warming stuff up. This would allow us to not carry the Honda 2200 with us when gone. We move around a fair amount so I should be able to keep the batteries charged. My question is what would you recommend for an inverter size, and if using the microwave for say 10 minutes, do you see a huge battery drain? Thoughts or ideas please. Thank you, Pat

[Veebyes]

It is all about understanding what uses what & smart power management. You are not at home with limitless power availability.

A genny running your charger is the fastest way to restore power to the battery bank. Run the genny at meal times when you might also want to use the microwave. That is also the time to be sure that anything rechargeable is put on charge.

Run the genny for a few hours in the morning till the battery bank is fully charged & when the CG does not have many around with people leaving or headed out for the day. Maybe doing the same as you. If everyone runs their gennys together, for the same reasons, nobody bothers anyone else with the noise.

[Ivylog]

For 10 minutes, start the generator. Pay me now or pay me later.

[BFL13]

You could run it for the 10 minutes on the two 27s IF they were fully charged to start with, but then you also have to get through the 24 hr day running the furnace etc until the next gen hours lets you recharge the batts.

With four 6s or four 27s and being able to recharge the batts at least every day (but only need solar each day in summer in the open for that--needs gen in winter under trees) can run the MW for 10 minutes to do spuds, then right after, 5 minutes to do frozen veggies. Meanwhile steaks get done RVQ outside.

The 15 min of MW time at 120a is not what matters with the four 6s. You still have to run the furnace and watch movies on those same batts.

It is all about scenario. When do you do this and how often? When are gen hours if any? Got any solar? Is there any sunshine in the forecast?

Good idea to run the gen to run the battery charger/converter while also using the inverter to run the MW. Different 120v source plug- ins of course--don't want any 240v!!!!

Same thing on 15 amp shore power if that is what you have at somebody's house you are visiting or at a fairground for dog trials. The converter input "supports" the inverter draw from the batts so it is not so hard on just two 27s for that 10 minutes. Means the 10 min is during gen hours in that scenario.

[time2roll]

zzyzxpat wrote:
I have 2 Group 27s deep cycle. Looking like this may be more than I thought just to run it for 5-7 minutes?

As long as you realize the most likely path will be a significant battery upgrade that is fine. Some do seem to manage on two batteries.

Don’t expect to cook dinner, run the furnace all night and wake up to make coffee on inverter also.

[zzyzxpat]

I have 2 Group 27s deep cycle. Looking like this may be more than I thought just to run it for 5-7 minutes?

[Trackrig]

I'm running four 6V batteries and a 2000W inverter. I use them to power my microwave for about three minutes only to heat a cup of something. I don't think I'd use it for ten minutes. Do you have four batteries or only two?

Bill

[Veebyes]

If it heats, cools or drives something mechanical it is a power hog. To get any meaningful power for any sort of duration you need a large battery bank. To get longevity out of the inverter you don't want to be demanding near 100% capacity out of it for any length of time. For voltage sensitive things, such as microwaves, you will need a pure sine wave inverter or risk the early demise of whatever it is powering.

If all of this is starting to look pricey, it is.

[theoldwizard1]

jkwilson wrote:
If you regularly use that kind of power and don’t have a recharging source like a generator or solar, you likely won’t get them recharged while towing. The generator is still the way to go.

Not true if you are using a DC-DC charger !

[NRALIFR]

I occasionally need to run our microwave from the inverter. It’s a very small unit that pulls about 950 watts total, so it’s slow. I only have one battery, a group 31 AGM. When we’re dry camping, I use a 1000 watt Yamaha generator for most of our power needs. The inverter is a 1500 watt pure sine. The Yamaha by itself can’t run the microwave directly, as it can only sustain about 900 watts.

What I found out by accident though, was if I put the microwave on the inverter while the generator is running, the 45 amp battery charger will kick in and supply about half the wattage, and the battery will supply the rest. Of course the generator kicks into high gear, but it doesn’t overload it. I can run the microwave like that for more than long enough to get a meal nuked. Also, it keeps me from having to turn off the Yamaha, move the shore power cord, then start the built-in generator just to run the microwave about 10 minutes.

The turntable motor in my microwave has been growling though, so instead of trying to find a replacement part for it, I’m going to find an inverter microwave that will fit and give that a try.

:):)

[3_tons]

Ran our Panasonic 850w (cooking watts only) conventional MW from two GC’s and a 2000w ProSine Xantrex (0004 cabling) for over a decade without a single glitch (typically up to a minute or two at a time), but a less demanding inverter MW would now be my choice…Robust cabling prevents excessive voltage sag…

3 tons

[2oldman]

zzyzxpat wrote:
if using the microwave for say 10 minutes, do you see a huge battery drain?

Yeah. You'll need at least 4 well-charged GC batteries for that, or lithium.

[wa8yxm]

BFL13 wrote:
You need a 2000w inverter for that job.

2nd a 2000 watt inverter at least 4 GC2 (400+ amp hours) of batteries properly connected HEAVY (00 or bigger) wire and keep it short. Tape the positive and negative wires side by side for as much of the run as you can. a 3rd pair of GC2 will extend run time.

Source on some of this is Xantrex.

[ktmrfs]

ok, there is an "easy peasy" way to run a microwave on a 1000W sine wave inverter. Been doing it for a decade or more. solution: Buy a panasonic true inverter microwave. rather than cycling between 0% and 100% power on reduced settings it runs continously but on lower power. the 50% power level easily runs on our 1000VA inverter, draws about 850W on that power level.

At 50% power level things like heating water, cooking frozen veggies etc. takes about 25-30% longer than 100% power.

Nice thing is we can use the microwave w/o having to go out and start the generator.

Now for the downside. If your battery bank is a PAIR of GC-2's, likely the inverter won't like the voltage drop if the batteries are below about 80% SOC. four GC-2's and your good down to around 50% SOC. Here is where a pair or even one 12V outperforms the GC-2's. The 12V has WAY less internal resistance and hence voltage drop. and a pair of 12V wins even more with the batteries splitting the current.

[jkwilson]

If you regularly use that kind of power and don’t have a recharging source like a generator or solar, you likely won’t get them recharged while towing. The generator is still the way to go.

[BFL13]

You need a 2000w inverter for that job. We do that all the time. You want a good sized battery bank to run that inverter such as four 6s. In a smaller Rv you could use LFP or SiO2 batts so the inverter will not alarm off while it is running the MW, but you still need AH to run the furnace etc that night. Just means recharge more often so keep the Honda handy!

Inverter at 120amps for 10 minutes is 20AH, not too much, but that is not the only AH draw for the 24 hr day of camping

Main thing is gen quiet hours. You can run the things off inverter early in the morning before gen hours let you recharge the batts. Same thing at night--watch movies off inverter, no gen noise, and then recharge with the Honda next day during gen hours.

With a TC you can carry batteries ahead of the wheel wells in the truck and then wire them up with the camper slid in part way so the wires will reach inside. That way you can carry four 6s, eg, two in the truck bed and two in the camper's battery box. Lots of ways around the problem.

Keep the Honda with you!