Small Cooker or Microwave

jandnrowe

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Hi all, I've space near 12v and 240v via an Inverter sockets, for either a small cooker or microwave. I don't expect to cook a full sunday roast with only 2 leisure batteries, but has anyone got experience of either? I've also got (not tried yet) Shore Power.
 
My boat has a microwave and it's fine for most things but I'm thinking of replacing it with a Combi that has micro/oven/grill.
This is the one I was looking at as ot is the same physical size.
Amazon.co.uk

At the moment it will only run if shore power or the generator is on.
The way the boat is wired only the socket for the TV was on the inverter but I have since changed it so it also supplies the one beside the dinette table that I put my computer monitor on.
Long term I'd like to have a leisure battery system that allows a bigger inverter but that's a long way off.
 
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Hi all, I've space near 12v and 240v via an Inverter sockets, for either a small cooker or microwave. I don't expect to cook a full sunday roast with only 2 leisure batteries, but has anyone got experience of either? I've also got (not tried yet) Shore Power.
You can power a microwave with an inverter, for short periods, a cooker would be a big ask with only 2 batteries, depending on the cooker and the size of the batteries.
 
We never use a microwave and swapped the Sanyo fitted to our boat with a Sage "Smart Oven Pro BOV820BSS". It is rated at 2.4kW so currently only available when we're on shore power but it is very useful and fits perfectly.

 
I fitted a gas hob but no oven and fitted a microwave which has a induction oven included running off either shore power of am inverter
 
Already mentioned that a cooker will use a lot of power. An induction unit will be better than an old style one with solid hobs. Calculation is trivial, just look at Watts per hob and estimate how long you'd cook for. e.g. 1,000W for 15 mins. is 250Wh and that's very roughly 20Ah from a battery. You will lose a fair bit more as there are losses and the higher the current the less actual battery capacity. So 25Ah would be closer. All rough estimates just to give an indication. That's a lot of drain for a single hob over a short period. Of course a light simmer will reduce the load a lot but heating water does absorb a lot.

A microwave will use less power as cooking times are shorter and no pans to heat. However, they lose efficiency with poor quality inverters and you don't use the W figure on the door. An 800W model might consume 1200W (guess). My inverter takes about 20% longer to cook on my Honda 2kW generator vs. mains power. That unit is considered to use a pretty good inverter. A cheap modified sine wave unit (marketing for square wave:D) might not work at all.
 
Hi all, I've space near 12v and 240v via an Inverter sockets, for either a small cooker or microwave. I don't expect to cook a full sunday roast with only 2 leisure batteries, but has anyone got experience of either? I've also got (not tried yet) Shore Power.
At home we have hardly used our cooker or our microwave since we got an air fryer.
An alternative to consider??
 
At home we have hardly used our cooker or our microwave since we got an air fryer.
An alternative to consider??
Similar comments for microwave. I imagine you'll be able to find a small 1,000W unit. Less heat loss due to the way they work and probably shorter cooking time. The food still needs the same amount of energy to cook but external losses are lower. I'd say you'd probably have less efficiency loss vs. a microwave so that's a plus. However, microwaving is itself more efficient. It would still use a lot from a battery. Say 25Ah as per my calculation above. You can reduce that if Wattage is lower or cooking time less.
 
Already mentioned that a cooker will use a lot of power. An induction unit will be better than an old style one with solid hobs. Calculation is trivial, just look at Watts per hob and estimate how long you'd cook for. e.g. 1,000W for 15 mins. is 250Wh and that's very roughly 20Ah from a battery. You will lose a fair bit more as there are losses and the higher the current the less actual battery capacity. So 25Ah would be closer. All rough estimates just to give an indication. That's a lot of drain for a single hob over a short period. Of course a light simmer will reduce the load a lot but heating water does absorb a lot.

1000W through an inverter will draw 100A, so your 25Ah figure is good.
A microwave will use less power as cooking times are shorter and no pans to heat. However, they lose efficiency with poor quality inverters and you don't use the W figure on the door. An 800W model might consume 1200W (guess). My inverter takes about 20% longer to cook on my Honda 2kW generator vs. mains power. That unit is considered to use a pretty good inverter. A cheap modified sine wave unit (marketing for square wave:D) might not work at all.
Most microwaves need a true sine wave inverter.
 
A microwave will need a perfect sine wave. A perfect sine wave inverter of 1KW or more will be big, very heavy and super expensive.
I think with an air fryer you can get away with a pseudo sine wave which would be somewhat more reasonably priced.
 
A microwave will need a perfect sine wave. A perfect sine wave inverter of 1KW or more will be big, very heavy and super expensive.
I think with an air fryer you can get away with a pseudo sine wave which would be somewhat more reasonably priced.
Agreed, it's basically a radiant element with a fan. Would be fine if there's one with no electronics, just a mechanical timer. Electronics may or may not work, depending on their design.

Don't ever plug an electric toothbrush charger into a modified sine+wave inverter. It might work but doubtful. Highly likely to never work again.
 
Agreed, it's basically a radiant element with a fan. Would be fine if there's one with no electronics, just a mechanical timer. Electronics may or may not work, depending on their design.

Don't ever plug an electric toothbrush charger into a modified sine+wave inverter. It might work but doubtful. Highly likely to never work again.
Correct. Been there, tried that and got the t-shirt. Several!
 
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