Microwave question

[cmcdar]

Hello all,

I'm new here and to solar power. I just set up my "off the grid" campsite this summer.

I have a battery bank of 4 six volt golf cart batteries and I have a 2000 watt inverter connected to it. I have a small microwave oven built into the kitchen of my camper.

The problem I am having is that the microwave will work. As in it will turn on and the carousel will turn and the time counts down BUT the food will come out cold. I brought in another small microwave and plugged it in and the very same thing happened. The microwave turned on and the carousel went round and round and the food came out cold.

Now the likelihood of both microwaves being broken the same way is slim so does anyone know what is going on? If so, any suggestions as to how to fix this problem.

Thank you,
Caryl

[peakbagger]

What sort of inverter do you have, there are two types, Modified square wave inverters (generally cheap units sold at walmart and parts stores) or pure sine wave inverters (usually more expensive). Electronics do not like modified square wave inverters so that may be the reason (although odd that two units have the same issue)

[Sunny Solar]

Usually microwave ovens work ok off MSW inverters. The only small problems the timer will be very inaccurate and things will take about 1/3 rd longer to cook than when its used on grid power..

[Robert1234]

Quick review of information suggests that some microwaves do not work with MSW at all, and those that do work will not heat as well (30-40% power reduction).

[cmcdar]

Thanks for the replies!

Damn! It was NOT cheap but it is a "modified sine wave" inverter. Who the heck would ever know enough to even think that there were two different kind of inverters.

Now I know that I have to buy yet another inverter... Hey, what the heck, it is only money.

Thank you again,
Caryl

[thastinger]

If you think that MSW one wasn't cheap wait until you buy a comparable sized PSW one.

[peakbagger]

First thing you learn with solar is "cheap" rarely equals "right" and inevitably most of the gear you buy initially is the wrong stuff. I can highly recommend a subscription to Home Power magazine and spend several months getting up to speed.

The only positive thing is that overall prices are coming down so your current lesson probably costs far less than it did a few years ago. There is nothing wrong with a MSW inverter for some sues so you may be able to sell it on Craigslist.

[Mike90250]

If you will be cooking with electricity (the most expensive way), you may want to consider going to a 24 inverter. You already have the batteries.
And pick up a induction hot plate too, they are really nice, but you need steel pans.

[cmcdar]

No cooking or heating with electricity.

I use electricity for only lights, a small TV, and a microwave. I even have a drip coffee pot that works on a propane stove.

So a new question - for a small microwave, will a 1000 watt pure sine wave inverter work?

Thanks again,
Caryl

[Sunny Solar]

it should work. as long as the batteries can maintain the current needed.

[geebus]

So a new question - for a small microwave, will a 1000 watt pure sine wave inverter work?

Check the back of your microwave. A 700w microwave refers to the 'cooking power' and I believe the input power of around 1250w.

So, you're more reasonably going to want a 1500w inverter, to give you room for manoeuvre, unless it's really low powered.
For the moment, I just fire up the generator if I want to use the microwave.

[Sunking]

No cooking or heating with electricity.

I use electricity for only lights, a small TV, and a microwave.

Sure about that? Last time I checked the microwave is for cooking and heating food and liquids.

[cmcdar]

Sure about that? Last time I checked the microwave is for cooking and heating food and liquids.

Ha Ha very funny!

[SunEagle]

Sure about that? Last time I checked the microwave is for cooking and heating food and liquids.

Don't forget the experiments to see how long a raw egg will last?

[Robert1234]

Don't forget the experiments to see how long a raw egg will last?

You might be really surprised at the real answer. Best quote I can give you...

"Farmers have 30 days from the day an egg is laid to get it to stores. Then, the stores have another 30 days to sell the eggs. The USDA recommends a maximum of 5 weeks in your refrigerator before you discard your eggs. What does this all boil down to? On April 1, you could be eating an egg that was laid on Christmas."

We raise our own chooks (as they say down under). We just leave 'em out on the kitchen counter. Don't even bother refrigerating them 'till after we wash off the poop (normally a week or two). WARNING: I'd never do this with a store bought egg.