Solar controller tie in
I am getting ready to install a couple solar panels on my 28' Keystone Springdale and am trying to determine how to get the charging to to the front mounted 6V batteries. I was thinking of running the...
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I use these, $12 on ebay for about any amp breaker you want. I use it as an on/off switch to disconnect the solar, or the batt, or the power lead to the 7-pin. With solar you probably never need the vehicle power, so break that connection. breaking it also means your trailer plug will not corrode as easily, no electricl voltage potential at the plug head (positive and negative terminals), mine are not corroding anyway.
For the panel safety you disconnect the panel before disconnecting the batteries, so the breaker makes this a lot easier to do.
The blister is great, I use that on a trailer.
Use Lap sealant as needed.
Closer to the batteries is idea, but maybe you can do that long run still; here is what I suggest:
Since you will put two panels up then run them in series - positive to negative then out. This is the same "in series" as you do for two 6 volt batteries.
This doubles your voltage so you have about 37 volts running through the wire, so you can use lighter gauge wire or use the same and have less voltage drop. The MPPT (and use MPPT) controller can take the 37 volts and drop it down to the 14 needed to charge. This is better than running two 18 volt wires down. Also, if one panel is putting out less voltage, from a bad cell, or shadow, or something is physically on part of the panel, then maybe you only have 35 volts, and this is still plenty, but if running 18 volt pairs, then you have issues.
Run the solar straight to the controller then straight to the batteries. Do not try to tie it in to something, many reasons for this, but just dont.
The controller may or may not need much venting. I had one in the space under the dinnette seat and it was fine, maybe that is enough air space, so maybe you can put it very close to the battery. It does need to stay relatively cooled though. Further away is ok, and the best place is somewhere where you can look at it often, but where the green indicator light does not keep you up at night (it will be bright when everything else is pitch black).
Closer is better because after the controller it will be a lower voltage, so there is more voltage drop. 37 (or 18) volts to the controller, then 14 after the controller.
For the panel safety you disconnect the panel before disconnecting the batteries, so the breaker makes this a lot easier to do.
The blister is great, I use that on a trailer.
Use Lap sealant as needed.
Closer to the batteries is idea, but maybe you can do that long run still; here is what I suggest:
Since you will put two panels up then run them in series - positive to negative then out. This is the same "in series" as you do for two 6 volt batteries.
This doubles your voltage so you have about 37 volts running through the wire, so you can use lighter gauge wire or use the same and have less voltage drop. The MPPT (and use MPPT) controller can take the 37 volts and drop it down to the 14 needed to charge. This is better than running two 18 volt wires down. Also, if one panel is putting out less voltage, from a bad cell, or shadow, or something is physically on part of the panel, then maybe you only have 35 volts, and this is still plenty, but if running 18 volt pairs, then you have issues.
Run the solar straight to the controller then straight to the batteries. Do not try to tie it in to something, many reasons for this, but just dont.
The controller may or may not need much venting. I had one in the space under the dinnette seat and it was fine, maybe that is enough air space, so maybe you can put it very close to the battery. It does need to stay relatively cooled though. Further away is ok, and the best place is somewhere where you can look at it often, but where the green indicator light does not keep you up at night (it will be bright when everything else is pitch black).
Closer is better because after the controller it will be a lower voltage, so there is more voltage drop. 37 (or 18) volts to the controller, then 14 after the controller.
