Can I run my microwave off of battery power?

[3TV]

I'm almost afraid to ask this, because this might just break the space-time continuum and cause irreparable harm to the ozone layer.
But, ... using my 2000 watt inverter, can I run my 1000 watt microwave oven off of my dual 6 volt batteries long enough to cook a frozen TV dinner (4 minutes).

[jharrell]

I run my microwave off my two Lifeline GPL-4CT 6V with 220AH and my Magnum 3000w inverter. Really no problem, short burst of high power.

I can run my 15k BTU air conditioner for at least 30-45 minutes continuous no problem to about 50% SOC and the microwave is similar draw.

Here is a video of me testing out the search mode on the Magnum with my monitoring software which I also run the microwave so you can see the draw off the batteries:

https://youtu.be/l_jqzY1wNDU?t=272

[Gottahaveit]

John is MitchF150 a few posts above with the video 😉

[3_tons]

pianotuna wrote:
3 tons,

My OEM Dometic microwave draws 1591 watts. I'm not about to replace it. It worked ok on a Cobra 2500 watt MSW inverter, and performs well with the Magnum 3000 PSW.

I have doubts that 210 amp-hours of GC batteries would power the inverter for very long.

Well if we meet up sometime, I’d love to run the air cond for a while (30-45 min w/comp cycling) and that might make a believer out of you (works on golf carts, eh??) - I love doing this and then watching folks gasp (for some pre-conceiveded bias?) in disbelief - I’d be more than happy to demonstrate....

As I stated, its usually NOT the GC’s that are the problem, its the equipment and/or the overall configuration - Inverter wattage is only one part of the equation, the equipment needs to be compatible in all ways to run optimally...

[pianotuna]

3 tons,

My OEM Dometic microwave draws 1591 watts. I'm not about to replace it. It worked ok on a Cobra 2500 watt MSW inverter, and performs well with the Magnum 3000 PSW.

I have doubts that 210 amp-hours of GC batteries would power the inverter for very long.

[3_tons]

I suspect that a few of the comments about GC’s are just guesses (WAG’s) and not from hands-on experience, or where equipment is marginal to begin with...

First off, not all inverters of ‘equal advertised wattage’ perform or see the loads the same - aside from MSM and PSW, surge ratings (as well as surge time) will vary depending on how robust the innards are ($$)...For some 2000w inverters are fine for light loads or resistance type loads, but will struggle with inductive or capacitive type loads...Costlier low freq inverters tend to be more robust that high freq models.

Second off, one must consider the AWG gauge and length of cable runs to the inverter. I only have room for two batteries... Cables are 7’ (round trip+ to -) 0004 ought...copper lugs are silver soldered and crimped...

Thirdly, MW ovens present a reactive load on an inverter...So why try to run a 1500w MW from a 2000w inverter? Is a 1500w oven truly needed for a camper?? Its far better to get by with a lower powered oven... Ours is a 800w (net cooking watts) Panasonic, but the actual gross wattage is likely closer to about 1050w or so...

Fourthly, We run our MW off of a 2000w PSW Inverter regularly from two 6v GC’s without a hitch...Inverter is capable of a 4500w surge for up to 5 sec... This set-up is even capable of running the 11kbtu air cond during brief roadside stops...

I hope this might clear up some of the mythology I often read about GC’s, as many of the perceived issues have more to do with a configuration (often overlooked), rather than the GC’s...

BTW, I’m running Costco sixers rated at 210 a/hrs total...(say it ain’t so - lol!)

3 tons

[larry_cad]

wa8yxm wrote:

jplante4 wrote:
I have 4 6v batteries and a 2000w MSW inverter. I've used the microwave for short bursts like defrosting with no issues. It sounds like it's unhappy but the amp draw was within expectations.

I did notice that the clock runs faster on the inverter.

Ok some science.. The clock runs faster because it is MSW.. Now.. I do not know if you know what a STILE is (Has 3 meanings I am familure with. IN one series of science fiction books it is the name of Citizen BLUE. He got that name (Which also means a pile of what the horse left behind) Because after looking at a pile of. Horse...stuff.. He diagnosed a horse as sick and a vet was able to easily cure saving his master (he was a slave not a citizen at the time) many bucks.

IT is also the name of the stairs that go up and over a fence. We had one on the SWINE side of the farm I grew up on . People (And cats) can cross but SWINE can not.

This last resembles teh MSW wave form.. Stair steps up and down. Usually 3 steps.. Flat topped. the clock reads every STEP not just the cycle as it does with True Sine.

Now if you draw a straight line at ZERO and look only at the POSITIVE side of the wave form the area under the stair steps is identical to the area under a same RMS Sine wave.. So you get 125V RMS. if you power an incandescent lamp or resistive heater. SAME SAME either way.

But the microwave is a peak reading. and the MSW is "Flat topped" so the peak is LOWER.. thus the Microwave has less power.

Oh and Steps are made up of all the odd harmonics 60hz. 180 hz (3rd harmonic) 5th 7th 99ths 1001th Eventually the filters cut them out but that is why they can mess up your TV and Audio systems.

And the steamer just said "DInner time" So I'll end this post here.

Excellent writeup. Had the steamer not called, I'm sure you would have elaborated on those "odd" harmonics and in particular, described how damaging they can be due to excessive heating of components because of the high frequencies.

What I do know is my Sharp MW REALLY doesn't like my MSW inverter, I mean REALLY!!!

[wopachop]

I cook frozen pizzas all the time on the stovetop. Get a pan with a lid and create a small oven. Just an idea if ever in a pinch and youre hungry.

[full_mosey]

nightshift wrote:

camperdave wrote:

nightshift wrote:
I nuke every day with my two 6v 435ah batteries. No genny, just 600w solar.

No fair though, that's a huge battery.

True dat. But I can't live without my L16s! Go big or go home.

That is the same as 4 x 6V GC = 440AHs.

BTW, I microwave anytime I want with 270AHs AGM. That is plenty big.

HTH;
John

[DrewE]

wa8yxm wrote:

jplante4 wrote:
I have 4 6v batteries and a 2000w MSW inverter. I've used the microwave for short bursts like defrosting with no issues. It sounds like it's unhappy but the amp draw was within expectations.

I did notice that the clock runs faster on the inverter.

Ok some science.. The clock runs faster because it is MSW..

The clock runs fast not so much because the inverter output is MSW rather than pure sine wave, but rather because the frequency of the inverter output is something like 60.1 Hz rather than 60.0 Hz and the microwave clock uses the power line frequency for its time reference.

[MitchF150]

Merrykalia wrote:
If the food has begun to thaw, it will not take as long to fully cook. Just use a thermometer to make sure it is up to temp - 165 degrees before you eat it.

If it's a TV Dinner, does it really matter? 🙂 (it's already been cooked at least one time and then frozen)

https://www.youtube.com/watch?v=C-6mI708yWc

Mitch

[Merrykalia]

If the food has begun to thaw, it will not take as long to fully cook. Just use a thermometer to make sure it is up to temp - 165 degrees before you eat it.

[wa8yxm]

jplante4 wrote:
I have 4 6v batteries and a 2000w MSW inverter. I've used the microwave for short bursts like defrosting with no issues. It sounds like it's unhappy but the amp draw was within expectations.

I did notice that the clock runs faster on the inverter.

Ok some science.. The clock runs faster because it is MSW.. Now.. I do not know if you know what a STILE is (Has 3 meanings I am familure with. IN one series of science fiction books it is the name of Citizen BLUE. He got that name (Which also means a pile of what the horse left behind) Because after looking at a pile of. Horse...stuff.. He diagnosed a horse as sick and a vet was able to easily cure saving his master (he was a slave not a citizen at the time) many bucks.

IT is also the name of the stairs that go up and over a fence. We had one on the SWINE side of the farm I grew up on . People (And cats) can cross but SWINE can not.

This last resembles teh MSW wave form.. Stair steps up and down. Usually 3 steps.. Flat topped. the clock reads every STEP not just the cycle as it does with True Sine.

Now if you draw a straight line at ZERO and look only at the POSITIVE side of the wave form the area under the stair steps is identical to the area under a same RMS Sine wave.. So you get 125V RMS. if you power an incandescent lamp or resistive heater. SAME SAME either way.

But the microwave is a peak reading. and the MSW is "Flat topped" so the peak is LOWER.. thus the Microwave has less power.

Oh and Steps are made up of all the odd harmonics 60hz. 180 hz (3rd harmonic) 5th 7th 99ths 1001th Eventually the filters cut them out but that is why they can mess up your TV and Audio systems.

And the steamer just said "DInner time" So I'll end this post here.

[nightshift]

camperdave wrote:

nightshift wrote:
I nuke every day with my two 6v 435ah batteries. No genny, just 600w solar.

No fair though, that's a huge battery.

True dat. But I can't live without my L16s! Go big or go home.

[MEXICOWANDERER]

New Panasonic 1000 watt Microwave

Old Trace MSW 4024 SB

Press start button to warm coffee 3 minutes

NYAYANNNNNT ZOOT! Odor of discrete parts overcooked.

Forty five dollars later repair outlet hands inverter to me with a replaced controlled circuit board.

Three weeks after, Trace failed. 4 FETS and 3 capacitors.

That learned me...

But your mileage may vary 🙂 ...

[DrewE]

road-runner wrote:

DrewE wrote:
If you're interested in microwaving at all frequently from battery power, I would suggest getting a Panasonic Inverter microwave. The reason is that using lower power levels on it actually lowers the peak power consumption, rather than simply cycling full power as other microwave ovens do. With a barely sufficient battery bank that can make a substantial difference.

I think they generally work well on MSW inverter power, too, without much if any cooking power loss.

Have you actually run a Panasonic "inverter" microwave on MSW? I wouldn't want to make a broad statement from a single trial, but I can say that the one time I tried it, the microwave didn't cook at all, on any power level.

No, I have not tried it. Based on the general circuit design principles, I would expect it to do fine, but I don't speak from personal experience--hence the "I think" rather than a statement of fact. (As I understand it, the inverter part is basically just a high-voltage switching power supply, rather than the high voltage line transformer and voltage doubler circuit used by typical microwaves.)