Hi, My wife and I have bought our first caravan - a 12/17 Jayco Journey Outback. It's an extremely well looked after van and we are thrilled with it. I'm quite handy mechanically but like a bag of hammers when it comes to electrics.
The van has the 100A/H AGM house battery which basically runs the lights, radio and tv. I think the management system is a BMpro 35B which I think supplies a max of 15A/H to charge said house battery. I would like to add another 100 A/H agm battery, being charged purely by portable solar panels, to run a waeco fridge. Can I use the same cable that charges the battery, to run the fridge but using 2 anderson plugs - one in and one out to the fridge?
I guess there would be more merit in having both batteries joined together to double the capacity, but then I would probably have to change management system? I would also need to buy new 2 batteries to be properly matched.
If what I have asked sounds like it would be impractical or not efficient, could someone please suggest an alternative idea, but in layman's terms so I can grasp the idea?
Thanks in advance
Randall
thomas01 said
07:25 PM Jul 10, 2022
If I understand what you are asking correctly, the simple answer is yes. As long as you are using a solar regulator from the panels all should be good. The solar panel is connected to the battery and the fridge is connected to the battery. Simples.
Robert.
Whenarewethere said
08:10 PM Jul 10, 2022
Like this but just on the fridge.
What is the total length from battery to fridge of the cable ( both + & - ) you need to calculate the resistance of both pieces of copper so there is not too much voltage drop. We can do it for you if you can't find an online calculator. So to be blunt if the length is 5 metres, you calculate 10 metres for resistance.
& the amps of the fridge.
You can join both batteries, you don't need a new charger other than if it is simply doesn't meet your loads, but the batteries need to have equal distance of wiring from the charger to each battery, or one length & equal branches at the end. Also the main feed would be to the positive on one battery & negative on the other, then jumper leads to each of the other battery terminals. Otherwise one batter will charge & draw more than the other which will wreck both batteries.
Portable solar panels. Bypass the controller on the back & get a proper one & put it next to the batteries. The reason is, again, voltage drop & it buggers up the charging profile.
But we can deal with one issue at a time!
bcd8238 said
08:11 PM Jul 10, 2022
Hi Thomas01, thanks for the reply. Yes, you deciphered my rambling question correctly. I appreciate your answer and quick response.
Happy camping
Randall
bcd8238 said
08:33 PM Jul 10, 2022
The cable length from the battery to the anderson plug for the fridge is 6 metres of I think, 8mm2 wire. The lead from the portable solar panel is the same thickness and about 10m long. I was going to use the panel mppt regulator as trying to join into the factory Jayco one would be very difficult based on where it is located. It's in a panel on top of the thetford van fridge and controls the rooftop solar panel.
With joining 100 A/H AGM batteries, I was under the impression that they had to be very close to the same age as each other.
Like I said, I'm not good with electrics and am keen to find out what I can do here. I really look forward to your sage advice.
Many thanks
Randall
Whenarewethere said
08:17 AM Jul 11, 2022
What are the fridge specs? No point doing all this twice!
It has been discussed recently. Using 2 controllers is ok but will cause issues if not set up correctly. The little controller can easily switch off the larger one. I tested this issue with two Victron MPPT controllers 75/10 & 100/20.
There are a lot of threads in this section. It took me a few years to get my head around this stuff & still learning every day. But the more I read the clearer things get.
My setup, a lot of technical data but I think you can kill a few birds with one stone thoroughly reading it.
i try to keep things simple i bought a 115 ah battery, a battery box , and a solar panel with mppt regulator from kings (4x4 super center ) all for under $400 ( buy them when on special) set it up in the canopy, all separate to electrical system of tug, basically just to run fridge in back of ute ,if the fixed panel on roof is not adequate(or parked in shade) i have a regulated portable panel that i can plug straight in via Anderson plug on battery box
how long the cheap 115 ah battery lasts is the unknown but a set up like this is simple only one battery to buy, one battery box, one solar panel fixed or portable all just about plug an play
it is simple an works for me
Whenarewethere said
10:33 AM Jul 11, 2022
One can knock their own self contained box with the components you want, or do it separately. Just have to built what one thinks is best.
(Not my battery box)
I made a few mistakes which cost extra even though I did a lot or research. One can only try to minimise redoing things!
bcd8238 said
06:13 PM Jul 11, 2022
Dogbox and especially Whenarewethere, many thanks for the very helpful information you have supplied. Certainly makes doing this stuff so much easier. I do apologise about asking a question that had been answered recently. I did do a search for any information prior to asking. Maybe I didn't use the right words in my search efforts, who knows.
All the installation is now done, ready for trips with the grandies.
Thanks again
Randall
Whenarewethere said
08:01 PM Jul 11, 2022
You need to use the advanced button, but it still only provides a limited list. Often easier just to manually look at thread titles & see if any are useful & save them.
I am sure you will find new projects on your travels to add to the system. It is usually the best way, travel then fix upgrade!
Hi, My wife and I have bought our first caravan - a 12/17 Jayco Journey Outback. It's an extremely well looked after van and we are thrilled with it. I'm quite handy mechanically but like a bag of hammers when it comes to electrics.
The van has the 100A/H AGM house battery which basically runs the lights, radio and tv. I think the management system is a BMpro 35B which I think supplies a max of 15A/H to charge said house battery. I would like to add another 100 A/H agm battery, being charged purely by portable solar panels, to run a waeco fridge. Can I use the same cable that charges the battery, to run the fridge but using 2 anderson plugs - one in and one out to the fridge?
I guess there would be more merit in having both batteries joined together to double the capacity, but then I would probably have to change management system? I would also need to buy new 2 batteries to be properly matched.
If what I have asked sounds like it would be impractical or not efficient, could someone please suggest an alternative idea, but in layman's terms so I can grasp the idea?
Thanks in advance
Randall
Robert.
Like this but just on the fridge.
What is the total length from battery to fridge of the cable ( both + & - ) you need to calculate the resistance of both pieces of copper so there is not too much voltage drop. We can do it for you if you can't find an online calculator. So to be blunt if the length is 5 metres, you calculate 10 metres for resistance.
& the amps of the fridge.
You can join both batteries, you don't need a new charger other than if it is simply doesn't meet your loads, but the batteries need to have equal distance of wiring from the charger to each battery, or one length & equal branches at the end. Also the main feed would be to the positive on one battery & negative on the other, then jumper leads to each of the other battery terminals. Otherwise one batter will charge & draw more than the other which will wreck both batteries.
Portable solar panels. Bypass the controller on the back & get a proper one & put it next to the batteries. The reason is, again, voltage drop & it buggers up the charging profile.
But we can deal with one issue at a time!
Hi Thomas01, thanks for the reply. Yes, you deciphered my rambling question correctly. I appreciate your answer and quick response.
Happy camping
Randall
With joining 100 A/H AGM batteries, I was under the impression that they had to be very close to the same age as each other.
Like I said, I'm not good with electrics and am keen to find out what I can do here. I really look forward to your sage advice.
Many thanks
Randall
What are the fridge specs? No point doing all this twice!
It has been discussed recently. Using 2 controllers is ok but will cause issues if not set up correctly. The little controller can easily switch off the larger one. I tested this issue with two Victron MPPT controllers 75/10 & 100/20.
There are a lot of threads in this section. It took me a few years to get my head around this stuff & still learning every day. But the more I read the clearer things get.
My setup, a lot of technical data but I think you can kill a few birds with one stone thoroughly reading it.
https://thegreynomads.activeboard.com/t65231112/custom-6x20-watts-solar-setup-with-mppt/
how long the cheap 115 ah battery lasts is the unknown but a set up like this is simple only one battery to buy, one battery box, one solar panel fixed or portable all just about plug an play
it is simple an works for me
One can knock their own self contained box with the components you want, or do it separately. Just have to built what one thinks is best.
(Not my battery box)
I made a few mistakes which cost extra even though I did a lot or research. One can only try to minimise redoing things!
All the installation is now done, ready for trips with the grandies.
Thanks again
Randall
You need to use the advanced button, but it still only provides a limited list. Often easier just to manually look at thread titles & see if any are useful & save them.
I am sure you will find new projects on your travels to add to the system. It is usually the best way, travel then fix upgrade!