OK I have 2x 120 AH house batteries in the caravan being charged - only by 450 watts of panels, flat mounted.
When running short of power, and I should say here, we have a few electronic devices including TV and vast, as well as a 12v compressor fridge. I have the ute set up with a DC-DC charger from the motor charging an aux battery, which can be plugged into the van to give an additional source of power.
The DC-DC charger in the ute will also take 25 watts of solar, one line of my thinking is to be able to fasten angled solar panels on the ute, the ute can be parked in the correct orientation to capture the morning sun.
Now the question for this line of thought is "Will I need to fit a second DC-DC charger for charge coming from the ute aux battery, with the DC-Dc charger mounted at the vans house batteries to over come any voltage drop so that the house batteries can be charged.
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-- Edited by iana on Sunday 23rd of September 2018 04:49:23 PM
I have 40 amp smart charger . Connected to generator or 240v on overcast days . When voltage is under or down to 12.5 by midday . When solar amps ( charge ) is low . 400AH system .,
HI
Treat vehicle and camper/van as 2 separate electrical circuits .
Circuit 1
starter bat to dc dc to aux bat in car to run car mounted accessories
Circuit 2
Master/starter batt
via 25mmsq // 3 b&s cable
to van mounted dc/dc preferably 30amp or greater unit [450watts solar around 27-30amps under full production]
cable size
25sqmm 35 amps load over 9mtrs is .4 volt drop [ideal for dc/dc charger in van ]
comparison
To small = 13mmsq 20amps load over 9mtrs is .4 volt
I'm guessing you mean 25 amps of solar output and not 25w Be aware that although the DC to DC chargers can handle solar as well, they are not very efficient at it. Not an issue when using the alternator as the power source because there is plenty to spare so a bit of loss isn't an issue, a very different thing when you consider the limited nature of solar panel output.
Personally, I'd look at installing the likes of a Plasmatronics Dingo or PL series controller that can handle all the solar you have plus any portables you want to add and a few amps spare so it isn't trying to run at full output all the time. This will give you the option to add an Anderson plug to the solar input and simply plug in the portables when you need them yet avoid and controller clash. The option of program 4 allows you custom set a charging regime that suits your use patterns to ensure you get the very best regime to keep the batteries closer to 100% SOC at the end of each charging period.
T1 Terry
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Gee Terry you have expensive tastes with the Dingo controllers - good, yes; Aussie made, I think yes.
What about Victron Blue Solar? See Outback Marine on the Gold Coast for what I think are the best prices - these are a lot better than some of the el cheapos on the market.
Ian, have you tried your van system out in full sun, partial sun? Your batteries should be able to get to 14.3v on charge & then float at about 13.3 to 13.5v. Like Terry, I'd suggest you leave the car out of it & just use the panels bearing in mind that you won't get 450w out of flat mounted panels (loss somewhere between 25 & 38%). With dissimilar panels, it is often best to have two controllers - one for each set of panels.
What is your total DC load?
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Warren
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If you don't get it done today, there's always tomorrow!
I have the "InterVOLT DCC pro" DC-DC battery charger fitted (Aussie Made). It takes 25amps of solar power, and has a MPPT charging controller for solar. The vehicle at the moment has an 80AH aux battery fitted which at present supplies the caravan, including all lights and braking, and also supplies 12v to the vehicle UHF and canopy lights.
I also have a 6 meter lead that connects between the vehicle trailer plug and caravan, and can and does supply 12v when needed.
A statement made by Terry "Controller Clash" so there is such a thing?
The solar regulators on the van are TPS555-1230 types, most likely typical Jayco.
-- Edited by iana on Thursday 27th of September 2018 06:25:17 PM
Another line of thought is to make the aux power in the ute the primary 12v power source, there are AGM batteries available that are about 500mm long 100w 250h, I could fit that inside the canopy, giving me about 300 AH (2 x 150). With a solar panel on the ute, that can be angled, plus alternator charging that would give us the necessary power to tide us over for a couple of days (winter).
But not using this power to charge the Van house batteries, the system remaining un-touched, except for addressing the long cable length from one solar regulator to the battery.
Free camping at the moment, just getting through with no TV or vast.
Be aware that although the DC to DC chargers can handle solar as well, they are not very efficient at it. Not an issue when using the alternator as the power source because there is plenty to spare so a bit of loss isn't an issue, a very different thing when you consider the limited nature of solar panel output.
