Solar Anderson plug for charging vehicle dual battery

[Dobbie]

We're about to go away again and, as said on other threads, are very satisfied with our solar charging capacity from van solar to van.

However, I have a little niggle as we are going south and I believe temps will be lower than we've been used to and sunlight hours are likely to be somewhat fewer so.....

I wondered about putting our spare 120 w solar panel on the roof of the car ( on roof rack so there's space under it) and getting an Anderson plug fitted to bumper bar, next to 12 pin and 7 pin already there so we can charge our second (dual) battery while chugging and be able to easily access that power while free camping.

My question is:

Will the Anderson plug, wired to the dual battery system, allow power to go both ways?

I want power input from the solar, and output for charging stuff while camping....from the same plug.

I think it will and will get the auto electrician to wire it up but, for some reason, I'm doubting myself.

( I really don't want an extra battery in the van and I already have a surplus panel and I want to keep it simple)

 

[NoWorries]

Yes
I have a Anderson Plug on the back of the Pajero and that goes direct to the second battery when I am camped I plug a 120w solar panel in and charge the battery but when we are on the move it is connected to the van to power the Fridge.
I have also connected it to the second Anderson plug at the front of the van and used the 200w solar on the van to keep the car batteries full.

If you get a Auto sparky to wire it get them to use bigger wire and a bigger breaker as mine is only 4mm and when I plug the compressor into the plug and start pumping the tyres it trips the auto breaker.

 

[Dobbie]

The same auto electrician who did the dual battery will be doing it so I'll make sure it's up to scratch.

I know I use the Anderson plug on the van for both input....the extra solar panel...and output ....the compressor ...and assume one on the car will do the same.

But you know what it's like when you overthink something....you begin to doubt.

And I'm slow!

 

[Drover]

The cable on Big Mal from drawbar to fridge is the size of a power line yet it connects to small cable at the fridge which feels like it will melt when its running, never checked the temp on the old rigs fridge cable.

 

[EDT82]

Yeah we have the set up you are talking about but with a foldable solar panel. I have a switch on dash to override the duel battery isolator. ( meaning I manually join both batteries together if main battery isolates itself. We also made a Anderson plug double adaptor so I can run lead to van aswell( joining van and car together if needed, but rarely) I also run ctek 250 dual 20 amp 5 stage charger ( in looks after batteries a lot better then solar regulator). Hope it helps

 

[Bellbirdweb]

I have the Anderson on the tug running to the 2nd battery and have 2 andersons on the van. 1 directly to the fridge which is what we mainly use, and another from the van batteries.

I can connect it and have the aux battery in the tug and the 2 batteries in the van all in parallel. That way I can have 300AH of capacity charging from the 2 solar panels on the van. I also have another fold up panel with 80w that I can add if needed, but have never needed any more solar.

 

[Dobbie]

Looks like I'm on the right track so I now have:

Red Anderson on car for ESC and wired to start battery so I can get input via solar and output via whatever is plugged in...ESC only but can use for whatever else if via a red plug

Grey Anderson on car wired to second battery ...both input and output (solar with separate regulator as usual) van will have that option as well.

and a double adaptor on fused lead , red and grey, if needed

and spare andersons with terminals removed and handles attached bolted together to give the car plugs some weather protection....and the wire ends are all bogged up.

I'm now over Anderson plugs but happy with my progress.

Two van batteries and two car batteries can be charged via dc or solar and we have access to 320 amps of battery, with the starter isolated.

And my new foldable panel is working beautifully. Very impressed with the quality.

 

[EDT82]

Looks like I'm on the right track so I now have:

Red Anderson on car for ESC and wired to start battery so I can get input via solar and output via whatever is plugged in...ESC only but can use for whatever else if via a red plug

Grey Anderson on car wired to second battery ...both input and output (solar with separate regulator as usual) van will have that option as well.

and a double adaptor on fused lead , red and grey, if needed

and spare andersons with terminals removed and handles attached bolted together to give the car plugs some weather protection....and the wire ends are all bogged up.

I'm now over Anderson plugs but happy with my progress.

Two van batteries and two car batteries can be charged via dc or solar and we have access to 320 amps of battery, with the starter isolated.

And my new foldable panel is working beautifully. Very impressed with the quality.

Very nice.. Well done.. I installed a ctek 250 dual 20amp 5 stage charger. This is top unit. It is a solar regulator aswell. It decides the best source to charge your batterys (alternator or solar). It eliminates voltage drop from long cable runs and is capable of 20amp battery charging(has capabilities to up amps). So that's stage 1 lol. Stage2 is the ctek smart pass. The lower unit. It allows you to use the fridge wire ran in the jayco. Meaning attached fridge wire to alternator fitting on ctek and them from another accessories fitting.. Run the wire back to fridge.. This allows fridge to run on DC batteries in van( not recommended 15 amp draw) and alternator to bypass ctek to run fridge up to 80 amps from alternator. The other little trick it does is smart passes power to all batteries to charge. Either ctek 20 amp or smart-pass 80 amp bypass. it is allway automatically calculating were to put power while still giving the fridge what it needs on the road.. We also placed 2 red Anderson plugs on van to pump extra solar panel in if needed. Lol. Just throwing a spanner in the works. Happy charging means happy camping

 

[Dobbie]

Totally agree about the 'happy charging means happy camping"

It's also a bit of a challenge to get it right...for someone whose skills are definitely not mechanical but keen to sort it out. I realised we bought our first solar panel in 1996 and had loads of people ar Lawn Hill looking at it. A very simple setup ...80 watts connected via alligator clips...but very new to the market.

When I think of what is possible these days I marvel.

I'm starting to think we might have overkill on our new setup but will wait till we have something to test it on before I adjust anything.

I love the quality of the ctek chargers ...have used two at home for years..but I needed a 25amp charger so decided to go with Projecta as the dc to dc charger is Projecta ...and comes with a remote monitor for the dual batteries. Also does the same as your ctek ...solar regulator as well and automatically selects source etc etc.

This has been a big learning curve for me..and I thought I was 12v conversant....but I'm now closer.

It's kept me off the streets and out of the shops....Shame about the lack of Christmas shopping.

 

[Drover]

Thats the grand plan for my set up, the panels are on the ute roof powering the aux battery and the engel can run off aux or main depends which anderson I plug into, the Cetek is still in the shop though...........the way my 12v for van fridge is wired I can't tell how fridge knows its got 12v as there is no physical connection couldn't find it in wiring diagram either. Its the auto Dometic set up, has 12v from van to run the circuit board, has me stumped.

 

[EDT82]

Its the auto Dometic set up, has 12v from van to run the circuit board, has me stumped.[/QUOTE]
So do you mean fridge auto selects DC Ac

 

[Dobbie]

Had to go down the same route in recent weeks as the new fridge requires constant 12v to keep the electronic panel operational but I didn't want any risk to battery capacity.

The Thetford draws 0.7 amps so they've convinced me it's ok to wire to van battery....and it won't automatically select 12v if I want it to run on gas. Sounds like your dometic ?

My gripe was the auto selector on the fridge panel. I'm now sure it can be manually overridden so think that'll be ok.

Wiring is as usual, with 12v charge from alternator while trundling but that's to keep the fridge going. Isolator protected as usual. When disconnected the only 12v power requirement will be for the stupid over designed fridge panel! I can live with that but will be interested to see how quickly we will have to get it on to either 240 or gas when camped just to protect the batteries.

I guess we need yet another challenge but I wish it was simple as we much prefer simple!

@Drover what's the 12v draw for the dometic for the circuit board?

(As demonstrated, I'm no expert but my research over the last few weeks might apply to your situation....and the things I've read about wiring variations for these new fridges freaked me out)

 

[Drover]

Yep it draws bugger all from the van battery to run the circuit, you just push the run button and it will select either 240, Gas or if they aren't available 12v, problem is the 12v supply from tug runs direct from anderson on bar to a 35amp relay at back of fridge, this has a wire from fridge circuit board to trip the relay, problem is it doesn't work , relay checks out okay but for the life of me can't see any way that fridge can sense there's 12v ??? I think it must have been a dodgy set up from the beginning, when I get really motivated I will get my toys out and see what I sort out but running on 12v isn't all that urgent as they don't loose much temp when on road for a few hours.
Just have to make sure the gas is turned off before hitting the road or it could fire up.

 

[EDT82]

Yep it draws bugger all from the van battery to run the circuit, you just push the run button and it will select either 240, Gas or if they aren't available 12v, problem is the 12v supply from tug runs direct from anderson on bar to a 35amp relay at back of fridge, this has a wire from fridge circuit board to trip the relay, problem is it doesn't work , relay checks out okay but for the life of me can't see any way that fridge can sense there's 12v ??? I think it must have been a dodgy set up from the beginning, when I get really motivated I will get my toys out and see what I sort out but running on 12v isn't all that urgent as they don't loose much temp when on road for a few hours.
Just have to make sure the gas is turned off before hitting the road or it could fire up.

Sounds like you all over it... Nice work

 

[Dobbie]

If you wander further than the beach you can always keep the beer and JD? In the trusty car fridge...agree that it's not really a problem while on the move but the relay sounds like a challenge.

There's always next year to tackle conundrums.

 

[Drover]

Just annoys me when things don't work but can hot wire in emergency, can't see what sort of emergency the fridge would need 12v to keep cool as 12v is useless for these 3 ways....................sorry for wandering again......................Engel keeps the beer cold in Ute, that stops then a MAJOR Critical EMERGENCY SITUATION is declared with nearest BCF or similar located just in case or at least the nearest ice machine...........safe at the moment as finances have decreed small stock of liquid hops available.......( blooody new house )