A fellow camper has told me that when using our inverter (We have two 90AH batteries, however the inverter is 2kw, which was fitted before we brought the van) I should ALWAYS start the engine as the start up power especially for the microwave is a massive drain and using the engine to charge the batteries while using the inverter is BEST !
However at this time of the year, that means that the internal lights will not work while the engine is running. As we would only be using the microwave for less than 20 minutes, is it REALLY correct that our engine should be running to keep the batteries up yo power?
A 2kw inverter is a huge drain on batteries, even for 20 minutes. Don't forget that the inverter itself consumes power on top of what the appliance connected to it draws. Personally I would think that having the engine running to keep the batteries topped up might be a good idea in theory, but it might depend on where you are at the time. On a quiet campsite with others close by you could risk annoying your neighbours.
My own policy is never to use batteries to provide any kind of heat, and that includes a microwave, but then these days we never go off-grid.
I hook up my van outside my house while she is parked up behind a set of gates to the mains, and flick a switch inside the van to switch between charging the van's battery and the leisure batteries.
Before I knew I had this switch, I was taking the van out every couple of weeks for a 12-mile round trip drive to charge the van's battery.
DK
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A 650w Microwave (which is the cooking power) will need about 1200-1500 watts to run so about 100-125Amps from the 12v system plus the current to power the inverter. Your maximum capacity of the batteries is 180 amps. so wouldn't last long you could try taking a voltage reading then use the microwave for whatever period you need then take a reading on completion you'll see a very quick loss of voltage I would imagine. hence the idea of running the engine, not the best solution though, mine would be to remove the microwave.....
We use gas if not on hookup. A small pressure cooker and gas oven do everything a microwave can. Certainly wouldn't run a microwave off batteries unless I had a deep hatred of the batteries and wanted to destroy them.
Hint: Another way to destroy them would be with a sledge hammer - probably more satisfying too......
quite honestly use your cooker - its cheaper to buy gas than replace your batteries, infact i would want another battery to the two you have before even thinking of using a microwave via a 2kw inverter. you have 2 x small 90amph batteries which means in reality you only have 90amph to play with before you start to damage your batteries - you shouldnt discharge more than half the charge in a battery otherwise its a slippery slope to new ones
If you think you really need a microwave in your van I would try to get a lower wattage one but really in my opinion there isnt really a need for a microwave in a van as you can do everything with the gas if you are not on hook up.
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Microwaves boil batteries dry in no time . I have had one in my HGV for years run off an Anderson lead into a 2500w inverter. I always crank the motor when using it. Rule of thumb is whatever the wattage of the appliance .. double that for the inverter.
We use our microwave a lot, however we always use sites with ehu, especially where there is no surcharge. Why wouldn't you? We need Sky TV to preserve OH's sanity.
I always say that the only two things that our 31 year old caravan doesn't have that new ones do is a microwave and air-con. I could include a TV, but we do actually have one we could take but don't choose to. Each to their own I suppose. We probably watch far too much TV at home so when we go away it's good to get away from it.
We are only really in the caravan for some meals and to sleep, except maybe when it's raining, and then we either play board games or read books.
Most new caravans, in fact the majority, don't have air con fitted.
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From the time I entered this notice, I have twice ran the engine while using the microwave and each time it has blown the 40 amp main fuse close to the battery. After this I have used the microwave without the engine running and have had NO problems either with the fuses nor the leisure batteries! My van has not been connected to the mains electric for many months, relying on the roof panel to maintain all the batteries.
I am a single camper and cooking from scratch for ONE person in the van is not worth the hassel, therefore putting a "ready meal" for one in the microwave and it's ready in about four minutes, is soooooo handy.
Quote: Originally posted by blueexpo97 on 11/7/2023
Most new caravans, in fact the majority, don't have air con fitted.
Yes, very true, and I don't think all of them have a microwave either. I'm inclined to think that the main changes to caravans since 1990 have been just styling. All the big changes came in the 1980s.