I have had the van parked outside with the 12volt only fridge going. The weather over the last two days has been overcast and raining. The in house batteries have tumbled and I have switched the fridge off.
I have 300 watts of solar power, doing hardly anything these last days, two 100 Amp hour batteries as house batteries.
I wired up the tug so that I have an auxiliary battery that has all the towing circuits coming of it, and a DC/DC charger separating it from the vehicle battery, so that if the aux battery goes flat, the vehicle battery is un-effected. In other words I have this available power.
I made up an extension lead of 9mm twin core cable to connect the vehicle to the van, with the idea of being able to charge the van house batteries from the tug, (with the tug parked beside the van) even if it meant running the engine.
From the information I got from this forum, I cannot charge the house batteries in the van because of the voltage drop, caused by the length of cable, and cable size. I except that.
Thinking about this, is there any reason why I can't connect the tug aux battery to run the fridge only, (its running voltage goes down to 11 volts) by a switch of some sort, bypassing the van batteries, so they can be re-charged by the van solar system and not have any load being dragged off them.
The other thing is what will happen if I just connect the ute aux battery to the Setec aux in connector?
I'm pretty sure the fridge comes off direct from the battery.
I hope that made some sense.
-- Edited by iana on Tuesday 26th of April 2016 07:14:25 AM
I have no certificates. This way what you are saying this will give you flexibility for when there is no sun for a few days even if it means running car motor.
Perhaps a second anderson plug to hook up the van batteries even if there is a small voltage drop it not the end of the world with out buying a second dctodc charger to place in the van.
When my battery starts to drop of a bit we ration our usage to save power just like we do with water, money, fuel and food until the sun shines once again.
Hope you understand this. It made sense to me. I read it 3 times.
Thanks Radar, its all so dam confusing. With the van 100% reliant on 12v power (We do have a gas stove though), and I am not happy about buying a generator because of noise, I tried to use the ute to augment the vans power. Also with these new vehicles, playing with the vehicle battery can upset ECU computer. So I left the vehicle battery alone, and via a DC/DC charger, use the vehicle aux battery for all 12v take-off I may have. It also means I can run the vehicle aux battery well down, and still have a fully charged main vehicle battery.
The aim was to mount solar panels on the ute canopy, come winter time when the sun was low on the horizon, the panels on the ute, moved away from any shade could be angled to make the most of the low sunlight. The DC/DC charger has a solar regulator built in.
Now plans seem to have come unstuck, because of voltage drop. I guess my next exercise is to connect up all the cable I plan to use, run some sort of load, and measure the voltage drops that occur. Its just turning out to be a touch expensive if it doesn't work out.
I guess if all else fails, just supplying the fridge with power would suffice.
~~~SNIP .... I am not happy about buying a generator because of noise, I tried to use the ute to augment the vans power. ~~~SNIP
Gday...
It is interesting how the "anti-generator" brigade seem to have instilled a fear of using a generator to augment a solar set-up.
Surely the noise of a vehicle idling for a few hours will be almost as noisy as a Honda genny on ECO ... and I would imagine a vehicle would use as much - or nearly as much - fuel.
I do understand that you are restricted in being able to 'control' all your 12V usage due to running the fridge, but Radar's comments on 'rationing' (just like water, fuel, food etc) how you use your power on overcast days is a common sense.
I run my fridge on gas (thankfully), but apart from that, when it is a rainy, or overcast, day, I simply use as little power as I can to give the panels at least a modicum of a chance to get SOME charge back into the battery before night hits. Thankfully in the now four years of having solar installed, I have yet to start the genny and have also suffered three or more days of overcast and/or rainy days.
Despite all that, I sympathise with your predicament in overcoming re-charging issues being totally 12v.
Cheers - John
-- Edited by rockylizard on Tuesday 26th of April 2016 08:51:12 AM
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2006 Discovery 3 TDV6 SE Auto - 2008 23ft Golden Eagle Hunter Some people feel the rain - the others just get wet - Bob Dylan
Hi all. Some times we seem to get too technical. Radar is quite right. I can put an extra five meters of good cable between the solar panels and the power may drop point two of an amp. Between the car alternator and the caravan batteries the car regular is the limiter. I have a direct wire through to the caravan and unplug it when I stop. Works for me. Remember the KISS theory and with 12 volts you can't go wrong. Cheers all. Woody46
