12v fridge isolator switch

mrangry

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I have just removed an old seafrost engine driven fridge compressor, evaporator plate and timer switch and I am replacing with a new air cooled electric system. The issue I have is that the old timer switch has left a hole in the woodwork about 85mm square. I would like to fit a switch to isolate the fridge, but reading online suggests that my initial idea of fitting say an ac 20A control switch would not work as the initial dc load would burn the contacts. Is this true and if so any ideas on a large faceplate switch that would cover the hole and do the job. The max current is 6.9 amps
 

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From post #1 "but reading online suggests that my initial idea of fitting say an ac 20A control switch would not work as the initial dc load would burn the contacts. "
DC switches have a bigger air gap between the contacts to prevent arcing. The one you linked to might be OK for a while, hard to say without knowing the specs, either way, the neon won't work.
 
I have just removed an old seafrost engine driven fridge compressor, evaporator plate and timer switch and I am replacing with a new air cooled electric system. The issue I have is that the old timer switch has left a hole in the woodwork about 85mm square. I would like to fit a switch to isolate the fridge, but reading online suggests that my initial idea of fitting say an ac 20A control switch would not work as the initial dc load would burn the contacts. Is this true and if so any ideas on a large faceplate switch that would cover the hole and do the job. The max current is 6.9 amps
Make a panel , from material of your choice that will cover the hole.

Buy a 12 volt DC rocker switch from Furneaux Riddall or 12 volt planet and fit it in the panel (16A and 20 A switches are available)

ITYWF even Halfords have suitable switches with a 16A DC rating
 
Make a panel , from material of your choice that will cover the hole.

Buy a 12 volt DC rocker switch from Furneaux Riddall or 12 volt planet and fit it in the panel (16A and 20 A switches are available)
Thanks, I just liked the idea of being able to cover the hole with an ac domestic faceplate as it would look a bit less diy if you know what I mean
 
My fridge has around a 5 second delay after switching on before the compressor fires up.
That must help with switching ?
 
Thanks, I just liked the idea of being able to cover the hole with an ac domestic faceplate as it would look a bit less diy if you know what I mean

A blanking plate to match the adjacent switch was my first thought but I dont think they are quite big enough.
 
Thanks, I just liked the idea of being able to cover the hole with an ac domestic faceplate as it would look a bit less diy if you know what I mean

Or, have a small custom panel made, material of your choice, small border perhaps, text to say "Fridge Isolator" or whatever. At 85mm square you could probably add something like a USB socket as well, if it didn't look out of place.
 
Is this a 12v DC circuit? If so a neon on the switch will not work, it is a mains AC indicator.!
The thing with using AC accessories on DC is that the break is slow, the breaking arc will pit or even weld contacts. Having said that I have found that a 20A AC switch has sufficiently large contacts to withstand this arcing. Seen lots used on DC without any problem.
 
My fridge has around a 5 second delay after switching on before the compressor fires up.
That must help with switching ?
It is normally when you switch OFF that you get the arcing. Plenty dc stuff available. Think Paul had the right idea. Make a coloured Perspex plate, or any other material of choice!
 
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