"Simple" electrics question - fridge

R

Rooster

Well-Known Member
Joined
12 Jan 2005
Messages
733
Location
NW England
Visit site
\"Simple\" electrics question - fridge

I'm fitting a Waeco fridge plate to my cool box. The temperature dial controller will be fitted above the worktop. I would like to "improve" the system by fitting an illuminated rocker switch to the controller case which will show when the unit is switched on so we don't forget to turn it off when leaving the boat, and it will allow me to turn it off without turning the temperature dial to zero. The controller has two wires. One in, one out. There's also a spare terminal.
Can anybody suggest a suitable switch and how it should be connected? Is a relay of some sorts required?

Thanks,

R
 
Re: \"Simple\" electrics question - fridge

There are two parts to the answer..

first off we need to know the power consumption (peak) of the fridge in order to select the correct switch.

And

You should have the fridge connected, at least, through your main battery switch so it can not be left on when leaving the boat. But it is always useful to connect a switch in line so you can turn off to save power. Though my switch is not illuminated, why waste the power to light a bulb, it all adds up.
 
Re: \"Simple\" electrics question - fridge

I would suggest that the fridge should be wired through a switch (typically 10 amps fused/breaker) on the electrical distribution panel; this panel is fed from the main service battery isolator switch. I would not rely on the thermostat as the only means of switching the fridge on/off; reason: if the thermostat should fail short circuit then you would have to switch off the main battery switch to isolate the fridge and consequently lose whatever else is being fed from the battery (typically VHF, nav lights e.t.c.).
I would suggest it is good practice to connect the fridge via a fused switch or circuit breaker on the main distribution panel.
Most small fridges draw about 4/5 amps maximum when compressor is turned on; so a 10 amp fuse/breaker should be O.K. but check the data sheet for your particular fridge.

Alan.
 
Re: \"Simple\" electrics question - fridge

Thanks for the advice. The fridge compressor is situated half a metre from the batteries. The switch panel is on the other side of the boat. Guessing I'd be OK mounting a single fused switch between the fridge and battery busbar?

R
 
Re: \"Simple\" electrics question - fridge

Technically I don't see why not, but it should be on the "load" side of the battery isolator. Check what cable size you will need for that length of run for the fridge load current.
 
Re: \"Simple\" electrics question - fridge

For me, a fridge that isn't turned off when I turn off the master switch would be a recipe for a flat battery when I arrive on board next time! Personally, I'd be inclined to make the effort to run the extra cable - it's a bit more effort now for a lot less aggravation down the line.

I have a switch for my instruments that has an LED built into it (from Maplin - change from a fiver, might only have been a couple of quid). It's bright enough that I'm unlikely to miss it, but only uses a minute amount of power. I wouldn't want to use a bulb illuminated switch.
 
Re: \"Simple\" electrics question - fridge

OK - this is going to open a new can of worms....but my bilge pump seems to be isolated with the battery isolator switch, hence this is left on except for maintenance work. Was told this is quite common.

R
 
Re: \"Simple\" electrics question - fridge

I purchased a very neat voltage sensing relay (can't remember the name but they advertise in PBO - circa £45), this automatically switches on the fridge when voltage reaches c13.5v and switches off when voltage drops to 12.8v. It has a red light to show when on or off &, the light is also a button switch that, when pressed activates the fridge for exactly 2 hours.

Brilliant bit of kit - really fit & forget, and is completely isolated automatically when the main switch is turned off. Well worth the money.
 
Re: \"Simple\" electrics question - fridge

I bought one of these for a friend's boat a couple of year ago and they are great. I was trying to contact them early this year to buy a couple of more and they were not replying to e-mails..... out of business??

Most new fridges have this feature built in now.

Alan.
 
Re: \"Simple\" electrics question - fridge

Re the fridge gizmo: I am pretty sure they are still going as I saw a small article or possibly advert in PBO or Sailing Today in approx Aug/Sep this year and had noted to follow up if I ever took decision to refrigerate my built in cool box, as it looked a really useful bit of kit.
 
Separate battery?

Because of anxiety about the fridge running down the service battery I fitted a battery just for the fridge. It doesn't matter iif I run that battery down. I have a second service battery for all the usual functions and a third very small battery just for engine starting.
Of course this opens up more problems of charging but its all easily soluble.
 
Re: \"Simple\" electrics question - fridge

Aimed ay my reply?!

I had read the previous post re the adverisement in PBO, my comment was directed at Alan's query as to whether the firm was still in business, as the earlier mention didn't say when it was acquired!

Just so you know /forums/images/graemlins/confused.gif
 
You must log in or register to reply here.

Share this page

Top