I installed an Anderson plug at the rear of my tug some time ago, it is connected to the battery via a circuit breaker and heavier gauge cable, this feeds the camper fridge only when travelling. Today I traded the camper on a newish camper (5 months old) which I pick up next month. The new camper is also fitted with an Anderson plug; however, this is connected to the campers single 100 AH battery, rather than rewire the camper 'll leave the camper as is and install an isolator under the bonnet of the vehicle. So, what's a decent isolator?
You could try a heavey duty relay 80 ~ 100 Amp are common and wire up the trigger wire to the ingnition. Or the pther one would be a battery isolator switch, these have a re moveable red key that you can use to turn the switch ( the load ) on. A lot of race cars use this type of switch to isolate the battery if the is a accedent. The key can only be removed in the 'off' position.
Hi Toglhot,a Redarc seems the way to go.You should power your fridge directly from the start battery and operate your relay through your ignition so that when you switch off your engine you also switch off the power to the fridge, no flat battery that way.Your fridge will work much better if you go direct from the start battery than trying to run it from the aux battery and charging the battery.Many do this but it is very uneconomical in power usage.
Your new camper presents not one but two problems you didn't have before, which can be both solved by one product.
Problem 1. How to isolate the tug battery from the camper battery when the engine is not running
Answer 1. A battery isolator in the tug.
Problem 2. How to actually charge the camper battery properly from the tug alternater. When the camper battery is put into the circuit the additional load will cause significant voltage drop over the more than 10 meters of connecting cable (there and back for a complete circuit). A 1 - 1.5 volt drop (measured under load) means perhaps only 12.5 -13 volts gets to the camper battery instead of 14 volts or more that is required to charge properly.
Answer 2. A DC to DC charger next to the camper battery.
Single product solution. A Ctek D250S Dual. it is a DC to DC charger, a solar MPPT controller, and an isolator when the tug battery input drops below 12.5 V. Approx $300 on evilbay. http://www.ctek.com/au/en/chargers/D250S%20DUAL
I agree with Hylife. Dc to DC charger is the way to go and the Ctek D250S Dual is hard to beat. I think Redarc has an equivalent but not sure. I use the Ctek.
I installed an Anderson plug at the rear of my tug some time ago, it is connected to the battery via a circuit breaker and heavier gauge cable, this feeds the camper fridge only when travelling. Today I traded the camper on a newish camper (5 months old) which I pick up next month. The new camper is also fitted with an Anderson plug; however, this is connected to the campers single 100 AH battery, rather than rewire the camper 'll leave the camper as is and install an isolator under the bonnet of the vehicle. So, what's a decent isolator?
HI
You have not given any info on the fridge,I assume it is a 3way, but what brand & model?
Are you saying that the fridge is connected to the camper battery?
If so a Dc/'DC charger " may" solve your major problem of isolating the fridge from the crank battery, when the engine is not running!
BUT depending on the wattage of the fridge, the charger may not have much to spare ,in power, to charge the camper battery
You should at least do what the FRIG makers specify & rewire the fridge with heavy cables to a spare on plug then with it's own feed to the crank battery with a fuse say 20A as close as possible to the crank & also fit one the many VSR in the pos line[ under the bonnet]or even a simple ignition controlled relay
-- Edited by oldtrack123 on Friday 25th of March 2016 12:05:15 AM