Camper electics
Submitted: Tuesday, Mar 02, 2010 at 03:01
ThreadID:
76473
Views:
3076
Replies:
3
FollowUps:
0
This Thread has been Archived
merchant
Hi all, i'm about to take delivery of a new camper and recently asked the supplier for a wiring diagram. They emailed one and I immediately noticed the builder installs/powers the fridge using a separate 12 volt supply from the towing vehicle rather than using the on-board battery to power the thing.
Is there any reason for this? I don't have a separate 12 volt line running to my trailer plug and will need to install one or do i just rewire the van so the fridge runs off the on-board battery whilst traveling?
If i have to install another line to power the fridge what wire size do you recommend? 6mm??
Reply By: Member - Vince B (NSW) - Tuesday, Mar 02, 2010 at 07:04
Tuesday, Mar 02, 2010 at 07:04
Merchant.
My Gulf van has 2 seperate lines.
The 3 way fridge runs from the cars system while driving & when camped it can run from the van battery(if needed).I only use the caravan battery for lights & water pump.The caravan battery is also charged with solar panels.
The wiring is 6mm & works fine.
Cheers.
Vince
AnswerID:
406821
Reply By: Mikee5 (Logan QLD) - Tuesday, Mar 02, 2010 at 09:04
Tuesday, Mar 02, 2010 at 09:04
To give a full answer you should supply a bit more info - what type of fridge, 3 way or 12 volt only and how does the trailer battery get recharged? What type of 12 volt connector does the builder fit to the trailer?
AnswerID:
406833
Reply By: olcoolone - Tuesday, Mar 02, 2010 at 10:19
Tuesday, Mar 02, 2010 at 10:19
The right way to wire up a 3 way fridge is straight from the car and to supply power ONLY when the car is running.
A 3 way fridge does not use a thermostat to control temp when on 12 or 240 volts, the thermostat only works on gas.
When a 3 way fridge runs of 12 volts they draw around 16 amps and anything up to 25 amps on some models.
This power draw would flatten a standard starting battery in good condition in about 2 to 3 hours.
Most camper trailer builders fit a single CHEAP 75 to 100 amp hour battery so your 3 way fridge would flatten on of them in 4 to 6 hours if the battery was charged to 100% state of charge (most vehicles will only charge battery's to 65% to 80% max state of charge).
If a battery is fully charged you can only safely discharge a battery down to 30% to 40% state of charge.
For your vehicle it would be advisable to use a 50 amp Anderson plug with 6 B&S cable running of the starter battery via a RedArc SBI12 Smart Solenoid and a 30Amp fuse as close to the start battery as possible.
And then use another RedArc SBI12 Smart Solenoid to control the camper trailer battery, or better still use a RedArc BCDC1220.
The other option is to use a Ranox DC-DC charger to control everything and use the vehicle run output wire to a relay to control the fridge when the vehicle is running.
Do not wire the 3 way fridge up to run on 12 volts when the vehicle is not running.....you will flatten battery's and become stranded.
DO IT RIGHT THE FIRST TIME AND SAVE HEADACHES AND MONEY
AnswerID:
406844