me me

Hi there,
I just wondered if an ordinary microwave would be OK on a boat, I have been looking at prices and the cost about 500 euro in the ship chandlers. Has anyone used a normal one?????

rugbymatt

nothing unless you specifically need a compact one or have no access to mains electricity.

me me

Rugbymatt
It does not need to be that compact. The size is much of a muchness. It would have to run of the boat batteries when out of the mooring.

rugbymatt

you would need one that is capable of running on 12/24volts or a good power inverter

me me

Thanks again rugbymatt, Other half is not here at the moment, and I freaked when I saw the price, could you tell mi if that is about the normal volts for a domestic micro?

rugbymatt

the only thing is that the 12 volt ones are usually rated at about 500 watts, which is very weak, and switching an inverter on with the microwave will end up killing your batteries unless they are being recharged at sea.

me me

I am sure they are recharged at sea when the engine is running, but I am not expert.

Spanish John

Hi
hope I,me not breaking any forum rules with this one,but you should ask on the link below,I used to have a Norman boat and the people on the web site below are very knowledgeable about all things boaty...
regards
John
www.normanboats.co.uk

me me

cheers John, I will have a look and see what Norman has to say on nautical topics Thank you for the link

teddy14

we used to use one off the generator as the batteries weren't up to it.

rugbymatt

wasnt sure if you are a sail type or motor type....

kenmcquade

me me,

BE CAREFULL..... others have mentioned my points below but you need to understand all points and your SAFETY needs as well.

I assume from some comments you have a sailing boat without a generator.

Your boats electrical supply will normally be 12V with 220/240V being available in a marina (if you have the shore connections)
Any normal sockets on your boat that you utilise (for say a tv ) in a marina have been supplied on a circuit that is designed for 220/240v shore supply only you will not be able to use these at sea for 12V supply.
An inverter will have to be connected to your batteries - not your engine start one ! and you will need to consider where the converter output socket will be in relation to where your MW (and anything else) is placed. On my boat engine compartment to Galley 10ft / 3m. Consider cables across the saloon !
Consider the size and quality of your batteries, an inverter trying to supply 800 watts from a 12v battery will require 70amps (depending on efficiency) and a 120ah will only give you 1.5 hrs approx supply (I know you will be using the MW for minutes but they all add up). Don't know what it will do to your charging / battery life

You could build in the converter and run cables under floors / behind bulkheads & paneling etc but you need marinised 13amp style cable for this option DO NOT try to connect to your current sockets.

Remember W=IxV Watts = Amps x Volts (800=4*220 approx or 800=70*12) The difference in 4amps to 70amps on a boat are HUGE as your normal boat cabling will be insufficient and will cause heat and fire risks !!!!!
Consider the type of cabling required for an electric windlass

Last point. Costs, the higher / extra costs should be for the MW to have been marinised. West Coast Scotland weather & non marinised equipment don't go well together - I don't know about SW Spain yet

Fred James

Yes, our boat had a perfectly normal 230v microwave oven. It worked fine if connected to a normal shore supply but if we wanted to use it while sailing/anchored then we used a 230v volt inverter to convert 12v DC to 230v AC. Alternatively we used our onboard 3 Kw diesel generator to run it.

If you use an inverter you must remember that a 600w oven actually needs an input of about 1300w to actually run it and the invertor needs to produce clean sine wave power (only available on the most expensive invertors) otherwise the oven will not work, or a worst self destruct!