12 v fridge
Submitted: Monday, Sep 20, 2010 at 14:44
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81438
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4
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kman1
hi all,
When running my 3-way caravan fridge on 12v(only while travelling) I am concerned I will leave it running when stopped and thereby flatten the caravan battery.To avoid this I'm thinking of installing a switch that will turn fridge off automatically when the switch determines the car has stopped moving and on when the car begins to move again.Has anybody had experience with this type of switch.
Thanks in advance kman
Reply By: Member - Geoff M (VIC) - Monday, Sep 20, 2010 at 14:52
Monday, Sep 20, 2010 at 14:52
Hi kman,
There is a switch on the market - its called "Fridgeswitch" and available through various outlets and on EBay.
I have one installed for my Dometic 3way, and it works fine.
Cheers, Geoff
AnswerID:
430855
Follow Up By: Member - Geoff M (VIC) - Tuesday, Sep 21, 2010 at 12:55
Tuesday, Sep 21, 2010 at 12:55
Extra note - I have run separate high current cables and anderson plug/s for the camper via a Redarc smart soloniod. This is essential since the 3way fridge draws quite a bit of current. The fridgeswitch protects the camper battery during rest breaks while travelling or if I forget to switch the fridge off 12V immediately.
FollowupID:
701732
Follow Up By: kman1 - Wednesday, Sep 22, 2010 at 16:36
Wednesday, Sep 22, 2010 at 16:36
Thanks Geoff,I have installed similar set up except have not installed fridgeswitch.
kman
FollowupID:
701842
Reply By: Member - Boobook - Monday, Sep 20, 2010 at 19:18
Monday, Sep 20, 2010 at 19:18
IMHO the best way is to run a seperate, heavy cable from a relay powered from the car battery activated by the accessories position of the keyswitch.
Run it to a couple of pins on a 12 pin trailer connector, or anderson plug and then run them to the fridge in the van.
Ie Totally seperate to the 12V system on the Van.
Then the fridge is powered whenever the car is running. By using seperate, heavy ( 6 AWG or better) you will get a lot less voltage drop and the fridge will actally keep things cold when you are driving.
If you use one of those fridge switches, the fridge power shares the ( almost certainly) inadequate wiring in your vehicle and van. The result will be food that goes warm and battieries in the van that are never really charged.
AnswerID:
430885
Follow Up By: kman1 - Wednesday, Sep 22, 2010 at 16:44
Wednesday, Sep 22, 2010 at 16:44
Hi Boobook,Before I started the 12v installation to car and van I intended to run separate cables for the fridge,however I was advised by a reputable 12v
shop that this would not be necessary if correct size cables were used.I have used 20mm twin auto cable.As I have'nt used the van with the new installation I can't say how it will work.
thanks kman
FollowupID:
701843
Follow Up By: Member - Boobook - Wednesday, Sep 22, 2010 at 18:58
Wednesday, Sep 22, 2010 at 18:58
Check the voltage across the terminals to the fridge and across the batteries in the van when the engine is running and the fridge on.
The problems are that you need about 13.8V to charge the batteries, and the voltage drop caused by the fridge will make it less than 12.8V for sure. It will never get charged properly.
If it is even lower ( and I think you will get about 12.3V at best) then your fridge wont get very cold.
I would be interested to see what you get. BTW I am not sure what 20mm twin auto cable is. Auto specified cable seems to be all over the place. Do you know the B&S or AWG size?
FollowupID:
701860
Follow Up By: Member - Boobook - Wednesday, Sep 22, 2010 at 19:02
Wednesday, Sep 22, 2010 at 19:02
Kman
With the cable, sure it isn;t 20A twin cable.
About what diameter is the copper bit of each cable in mm, and what would be the overall dimensions inc the sheath?
FollowupID:
701862
Follow Up By: kman1 - Thursday, Sep 23, 2010 at 13:38
Thursday, Sep 23, 2010 at 13:38
Hi Boobook,
Can't
check voltage as have'nt purchased battery.
Each of the two cables are 6.5mm Dia.copper core and 8mm Dia. outside the sheath.
As I indicated my research told me I needed a separate cable for the fridge however I was advised by the specialist 12v
shop that this was not necessary if the cable was sized correctly.
Will
check voltage when installation is complete.
kman
FollowupID:
701954
Reply By: kend88 - Monday, Sep 20, 2010 at 19:23
Monday, Sep 20, 2010 at 19:23
When I had an Anderson plug installed to run my fridge when travelling I asked my Auto Elec to set it up so that it would not draw from the battey when the keys were turned off.
He said they are always installed that way unless someone specifically asks for it otherwise.
KenD
bris
AnswerID:
430888
Reply By: Ray - Monday, Sep 20, 2010 at 21:00
Monday, Sep 20, 2010 at 21:00
My 3way is 12v powered from a 150 amphr battery in the caravan but with a relay, these batteries are isolated from the fridge as soon as the ignition on the car is turned off.
AnswerID:
430904