Microwaves on inverters.

[doughere]

I have a unit with 1500 watt microwave and would like to be able to use it occasionally when dry camping (10 min or less at a time). I plan to use a 2000 watt pure sine wave inverter. Also plan using it on a 900 watt coffee maker (about 15 min a pot). Anyone have any experience with this setup?

Thanks,
Doug

[crcr]

I suggest that you put a Kill-a-Watt meter on your microwave and measure the draw. I did that to the OEM small microwave in our 2011 Jayco TT. Since it was a smallish microwave, I figured it would draw 800-900 watts, but was rather shocked to observe that it draws 1425 watts continuous when running!

[Veebyes]

We have a 1500 continuous pure sine wave inverter. Standard setup procedure when dry camping is turn the microwave, water heater, fridge & charger breakers off. Eliminates all chances of expensive things happening.

[mchero]

Good point MrWiz!

[MrWizard]

Yes 200 ampHrs will carry a 2000 watt inverter for 'most' loads
When charged up
But what will it do in the morning, after a nights use
2 minutes for a cup of hot water ..sure
10 minutes of MW...maybe, but you are going to need some recharge time
From some source
You are not going to get 3 or 4 days in a row with a heavy morning routine with out daytime charging,
if you do it could have serious effects on your battery life

[deltabravo]

doughere wrote:
I have a unit with 1500 watt microwave and would like to be able to use it occasionally when dry camping (10 min or less at a time). I plan to use a 2000 watt pure sine wave inverter. ... Anyone have any experience with this setup?

Thanks,
Doug

Yep. This Doug has experience with it.

I've used a 200 amp hour battery bank and a 2000 watt inverter in 3 RVs now, 2 of which are still in my fleet (the ones in my signature).

WORKS PERFECT!
Truck camper has a Xantrex PS2.0.
Nash has a Victron Multiplus 2000 and 2 Battle Born batteries

Here's the system in my truck camper

Another video

AGM batteries in my truck camper

[mchero]

otrfun wrote:

crosscheck wrote:
Got any room under the dinette seating? we had 4 AGM batts under the seating in our TC for 5 years. The 4 batts in a square did not take up that much room.

Dave

Unfortunately, no. Thanks though!

I LOVE my Onan 7500 Quiet Diesel. Quiet and sips the diesel. Don't think i can ever go back to a gas generator!
My wife fell in love with the convection microwave. When boondocking we use the genset.

[otrfun]

crosscheck wrote:
Got any room under the dinette seating? we had 4 AGM batts under the seating in our TC for 5 years. The 4 batts in a square did not take up that much room.

Dave

Unfortunately, no. Thanks though!

[2oldman]

doughere wrote:
I have a 2 K Honda; I HATE running generators.

Me too, and I have 3 of them, and I'm sure not starting one up in the morning for coffee. Your idea is fine as long as you have at least 4 gc batteries, and preferably a pure sine inverter.

[Gjac]

doughere wrote:
I have a unit with 1500 watt microwave and would like to be able to use it occasionally when dry camping (10 min or less at a time). I plan to use a 2000 watt pure sine wave inverter. Also plan using it on a 900 watt coffee maker (about 15 min a pot). Anyone have any experience with this setup?

Thanks,
Doug

You don't say how many or what type of batteries you have, which will make a big difference in the answer to your question. I doubt you will get 10mins of MW use on one 12v battery. Also it depends on how it is wired and the gauge of the wire. I have a 1500 watt MSW inverter with 2 6 volt CG batteries. I can use the microwave when traveling down the road just fine. When stopped I can get several mins of use. 5 mins with the microwave will set off the alarm. After 15 years of dry camping I rarely use the inverter any more. Coffee is made on the stove, refer is run from propane no longer from inverter, small electronics like laptops are charged with a 150 watt plugin inverter. I hate to exercise the genset each month as general maintenance so I look for ways to actually use it with out just wasting gas, so microwave use on rare occasion or electric chain saw for campfires is about the only time it actually gets used, never to just recharge the batteries. I know others have more electrical requirements than myself like TV, radio, etc, so larger battery banks and 2000 watt inverters make sense , but for general dry camping, fishing, hiking enjoying nature without electronics I think a large inverter is not necessary. At least that is my experience.

[marcsbigfoot20b]

ktmrfs wrote:

doughere wrote:
I have a unit with 1500 watt microwave and would like to be able to use it occasionally when dry camping (10 min or less at a time). I plan to use a 2000 watt pure sine wave inverter. Also plan using it on a 900 watt coffee maker (about 15 min a pot). Anyone have any experience with this setup?

Thanks,
Doug

run our microwave quite often on an inverter. you will need enough battery and big short cables from battery to inverter.

Now one thing to consider, which we did was to toss the original microwave in the donate pile and buy a panasonic true inverter microwave. It's operation is much different than traditional microwaves. when in partial power mode it doesn't cycle between 0% and 100%, it actually runs at the % set. So.... if you set it to 50% that's what it runs at continually. Ours is a 1500watt microwave and I run it easily on a 1000W inverter if power is set to 50% or less. At 50% power it does NOT take twice as long to heat something, more like 25% longer.

I also have a hotel type keurig that draws 900W and we run it off the 1000W inverter with no problems either.

for this type of draw I'd recomend either 4 GC2s or a bank of 12V. GC2's aren't great for large current draw and have high internal resistance compared to a 12V jar. So with only 2 GC2's your inverter may shut down when batteries are below 75%ish SOC. With 4 GC2's it should work down to 50%. I run 4GC2's, with only 2 it only worked with batteries charged above 75% or so. A few others have had similar experiences.

Same here....ditched the OEM microwave and got an inverter microwave. Cooks more evenly at 40-50% and uses less peak power with no cycling from 100% to 0 to 100 and irritating my psw inverter, even though with 3 AGM deep cycle 100 ah batteries and 360 watts of solar it never made a peep anyway. Would work with two 6 volts also at level 5 without the low voltage alarms.

[crosscheck]

bid_time wrote:
The batteries are only half of the equation. What do you do so you can run the coffee maker and microwave the next day? And what about the times when the sun doesn't shine for 4 days? And what is the cost of that side of the equation?
Just buy the generator and be done.

We have a Honda i2000W inverter generator which we carry all the time. Might as well be a boat anchor. Never use it. Batteries are more than half the equation. They keep you going through the highs and lows of solar if you have enough AH. The inverter is the silent answer to the generator. Even in shade or cloudy conditions, we can harvest 4 A from the panels(high of 22A/hr). Our Micro in 4 minutes uses 12.5 AH which is around 3 hours of low sun. We have 450AH of available storage.

If you are the type that dry camps or boondocks like they are at home, then you will be running your genny constantly and running out of water within a few days.

If you camp like you are in a back country environment without the luxuries of home, then without giving up too many comforts, a few simple conservation choices for power and water will see you staying a lot longer in the bush without alot of genny noise complements of your hard working batteries, solar and your inverter.

Dave.

[crosscheck]

otrfun wrote:
Takes about 110a (12v) to power our microwave with 2 GC2 batteries using a Xantrex 2000w PSW inverter. We can power the microwave for almost 40 minutes before the batteries are down to 12.2v. Our inverter to battery cable run is almost 13 ft. so we used 4/0 cable. Even at 110 amps we only have a .15v (1.2%) drop.

FWIW, the Xantrex low-voltage alarm activates when the load voltage drops below approx. 11.3v. We've had it down to almost 11.0v (with a 110a load) without it shutting down. Output voltage was down to 109vac at that point. The Xantrex has a very low no-load draw--approx. 700ma.

Pretty pleased with the overall performance of everything. Would love to use 4 GC2's, but no room for 'em in our truck camper.

Got any room under the dinette seating? we had 4 AGM batts under the seating in our TC for 5 years. The 4 batts in a square did not take up that much room.

Dave

[time2roll]

bid_time wrote:
The batteries are only half of the equation. What do you do so you can run the coffee maker and microwave the next day? And what about the times when the sun doesn't shine for 4 days? And what is the cost of that side of the equation?
Just buy the generator and be done.

I have a 700 watt Ryobi propane generator for circumstances of several days of no sun or some other near fatal situation. Only puts 40 amps into the battery, not going to run the MW direct.
Inverter does run silent during quiet hours.

[otrfun]

Takes about 110a (12v) to power our microwave with 2 GC2 batteries using a Xantrex 2000w PSW inverter. We can power the microwave for almost 40 minutes before the batteries are down to 12.2v. Our inverter to battery cable run is almost 13 ft. so we used 4/0 cable. Even at 110 amps we only have a .15v (1.2%) drop.

FWIW, the Xantrex low-voltage alarm activates when the load voltage drops below approx. 11.3v. We've had it down to almost 11.0v (with a 110a load) without it shutting down. Output voltage was down to 109vac at that point. The Xantrex has a very low no-load draw--approx. 700ma.

Pretty pleased with the overall performance of everything. Would love to use 4 GC2's, but no room for 'em in our truck camper.