Inline switch for 12v mini fridge

whitevanwoman

Guest
I have a little fan type 12v fridge (the type which keeps a 4 pack of beer cool) which is wired direct into my smartcom relay so that it runs whilst the engine is running and continues after the engine has stopped until the leisure battery drops to a certain level. Whilst the leisure battery is discharging and before it reaches the cut off level, the fridge clicks on and off, the periods of time getting shorter and shorter until it finally stops. This can take several hours and is particularly annoying during the night because of the noise of the fan.

There is an on/ off switch at the back of the fridge but it's awkward to get at as it means pulling the fridge forward and scrabbling around behind it.

So I'd like to put an inline on / off switch into the wiring and need a little advice...

Firstly, could someone give me a link to the right type of switch on ebay - I was in Maplins yesterday and there was loads of different types of switches but I didn't know which one I'd need.

Secondly, where in the line should the switch go? There is an inline fuse between the smartcom relay and the fridge, so should the switch go between the relay and the fuse or between the fuse and the fridge?

:confused: Hope this all makes sense. Thanks.
 
n brown said:
oh isn't as stupid as he says.anyway,Snap-in Miniature Round Rocker Switches : Rocker Switches : Maplin Electronics drill a 20mm hole put between fuse and fridge
Click to expand...

Thank you :cheers:

Another question - I have wired a single 12v cig socket directly off the leisure battery (ie not through the smartcom) - the wires look really really thin and I'm wondering what load they can take, and so what I can or can't plug into the socket. Also I picked up a couple of spare inline fuse holders at Maplins, and am wondering whether I should put a fuse in the cig socket wiring if I want to use it to recharge my laptop or plug 100w inverter into etc. If so, what size fuse should I put into it?
 
Most of those Cigar plug ins have a fuse in them. Just take it apart and have a look.
 
Your cig socket should have an inline fuse as near to the leisure battery. The fuse in the socket protects the load and the inline protects the "thin" wires? A 100w inverter is going to take possibly 8+ amps so you will need to ensure your "thin" wires can carry that.

Edit. Not sure if cig socket will have fuse. In-line fuse essential as near to leisure battery as possible
 
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It's one of these... 12v Accessory Socket With Battery Clamps Crocodile Clips | eBay

I cut the croc clips off and wired it directly to the leisure battery - I have a 3 way socket + USB adaptor to plug into it which has a 5 amp fuse in it but there's no fuse in the socket.

So am wondering whether it needs a fuse in it if I plug something like the laptop, inverter direct into it instead of via the fused 3 way adaptor.

I've learned the hard way that the 5A adaptor can only cope with one higher powered item at a time, and now have a plentiful supply of spare 5A fuses...
 
The inline fuse would need to be 5amp for this extension. This fuse is there to protect the cable in event of a fault. As you have wired it direct to the battery if a fault occurred the cable would burn out with the possibility of fire. Whatever you plug into the socket should have its own fuse rated accordingly. It would be better if you wired your inverter directly to the leisure battery through a switch and inline fuse.
 
And another question...

Yesterday someone gave me a secondhand 110 leisure battery from their motorhome - apparently the battery is good, was last used about 2 months ago and powered a laptop for 4 days without recharge.

I currently have a 85 leisure battery wired in which was also donated secondhand from a caravan user and which has been fine so far over the past couple of months for powering the fridge whilst travelling, and for LED fairy lights, mobile phone charging and stereo power when parked up.

I'm wondering whether to simply swop the batteries and keep the 85 as a spare / back up, not wired in but able to be swopped with the larger battery if needed when parked up for more than a day or two and the larger battery is getting low (not likely to be that often, I rarely stay in same place more than 2 days)...

Or whether I can connect the 2 batteries together so that both charge off the vehicle battery when running...

I have a 4 watt solar panel with croc clips which can be used to keep a spare battery fully charged on trickle charge. It's not bad, on a sunny day it put a fair bit of juice back into a low battery within a few hours, not enough to fully charge but certainly enough to keep a full charge maintained.
 
shortcircuit said:
The inline fuse would need to be 5amp for this extension. This fuse is there to protect the cable in event of a fault. As you have wired it direct to the battery if a fault occurred the cable would burn out with the possibility of fire. Whatever you plug into the socket should have its own fuse rated accordingly. It would be better if you wired your inverter directly to the leisure battery through a switch and inline fuse.
Click to expand...

Thanks for this :cheers: I had an idea that it should be fused and so picked up a couple of spare inline fuse holders from Maplins yesterday. Will get that sorted.

To wire the inverter direct into the battery, is it simply a case of cutting off the 12v plug and wiring it direct to battery? Will the inverter be fused or will I need to put an inline fuse into the wiring to the battery? The inverter has it's own on / off switch - will it need another switch in the wiring?
 
As I have said the in-line fuse is there to protect the wiring to the inverter and should be fitted as near to the leisure battery as possible. You need to check if the inverter has its own fuse or if its fuse is in the plug you are cutting off in which case the inline fuse will suffice. No additional switch will be required.
 
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With regard to the batteries, they are different ages and capacities. Probably not a good idea to connect them together permanantly so they both charge at the same time. Because of the different ages, one will likely be stronger than the other and dicharge into the weaker one. But the best idea would be to keep the second one charged up as a spare, and swap it in if needed on the quick release clips.
 
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