Hello all,
The P.O.S. Zamp/Sunpower flex panels on my motorhome (2018 Winnebago View 24V) died. I'm getting a sub-optimum warranty replacement from ZAMP of two 90w rigids.
So - I am going to take the opportunity to just upgrade.
Current system:
1) ZAMP 30A controller
2) Progressive 30A charger
3) Xantrex 2000W Prowatt Pure Sine 12V inverter
4) Two GC-2 6V batteries
5) Two (now dead) 100W flex solar panels feed into a parallel roof cap. This roof cap has to go as it was under-engineered by ZAMP by installing a 12V/40A circuit breaker inside the combiner and the inputs are paralleled. I haven't checked the gauge of the wire coming out of the combiner to the controller but I'm guess I will need to upgrade that as well.
What I am planning on:
1) Two 12V DIY LiFePo4 packs - each with a 100A+ BMS and each with 200+AH capacity. Yield - be able to occasionally pull a full 2000W out of inverter with each pack discharging at 0.5C and 400+AH total capacity (but mostly long-extended dry camping without having to start the generator.)
2) Solar - would like to put 600+W on the roof. I have the room. Have looked at six 100W compacts or three 200-210W panels (either 12V or 24V class depending ...)
3) Charge Controller. This is where I am stuck. 600W puts me in a weird space I think. Three 210W Newpowa 12v panels would put me at 60Voc and 12.5A current - but I need a charge controller that can push ~40-50A to the battery pack.
I've also toyed with going with 24V. But that would require going with a new 24V inverter, adding a 24Vto12V buck, a 12Vto24V controller if I want to charge off the alternator - and leaves me in a quandary on what to do with generator starter (permanent magnet direct drive - so it would run but at twice normal speed and would probably overheat pretty quickly.) If I didn't already own a 2000W inverter, I might think strongly about going this route but probably not worth the cost of replacing the inverter since I don't have a use for it elsewhere.
My questions:
1) Advantages/disadvantages of different paneling approaches to get to 600W. Six 100W could be in a 3S2P or 2S3P or 6S. Three 210W panels just 3S or 3P. One note - the charge controller is currently in a void above the refrigerator. If I go to higher power -that is probably not the best place for it (it was chosen by manuf. because it is right under the roof cap.) So a new charge controller should probably go in a storage bay that is right next to the battery compartment - meaning the run from the roof to the controller will be longer - which would make me lean towards higher voltage.
2) Charge controller. This is an attempt at a (somewhat) budget build. Would like to not blow the bank on the charge controller and am willing to compromise on specs of it means substantial cost avoidance. That includes dropping down from 600W to 500 or even 400. I do have a generator after all - and if I replace the converter/charger with a higher amp output, I can always squeeze power back into the batteries while I run the air conditioner off the geny. Basically - looking at managing total project cost including panels,MPPT, and possibly converter/charter.
The P.O.S. Zamp/Sunpower flex panels on my motorhome (2018 Winnebago View 24V) died. I'm getting a sub-optimum warranty replacement from ZAMP of two 90w rigids.
So - I am going to take the opportunity to just upgrade.
Current system:
1) ZAMP 30A controller
2) Progressive 30A charger
3) Xantrex 2000W Prowatt Pure Sine 12V inverter
4) Two GC-2 6V batteries
5) Two (now dead) 100W flex solar panels feed into a parallel roof cap. This roof cap has to go as it was under-engineered by ZAMP by installing a 12V/40A circuit breaker inside the combiner and the inputs are paralleled. I haven't checked the gauge of the wire coming out of the combiner to the controller but I'm guess I will need to upgrade that as well.
What I am planning on:
1) Two 12V DIY LiFePo4 packs - each with a 100A+ BMS and each with 200+AH capacity. Yield - be able to occasionally pull a full 2000W out of inverter with each pack discharging at 0.5C and 400+AH total capacity (but mostly long-extended dry camping without having to start the generator.)
2) Solar - would like to put 600+W on the roof. I have the room. Have looked at six 100W compacts or three 200-210W panels (either 12V or 24V class depending ...)
3) Charge Controller. This is where I am stuck. 600W puts me in a weird space I think. Three 210W Newpowa 12v panels would put me at 60Voc and 12.5A current - but I need a charge controller that can push ~40-50A to the battery pack.
I've also toyed with going with 24V. But that would require going with a new 24V inverter, adding a 24Vto12V buck, a 12Vto24V controller if I want to charge off the alternator - and leaves me in a quandary on what to do with generator starter (permanent magnet direct drive - so it would run but at twice normal speed and would probably overheat pretty quickly.) If I didn't already own a 2000W inverter, I might think strongly about going this route but probably not worth the cost of replacing the inverter since I don't have a use for it elsewhere.
My questions:
1) Advantages/disadvantages of different paneling approaches to get to 600W. Six 100W could be in a 3S2P or 2S3P or 6S. Three 210W panels just 3S or 3P. One note - the charge controller is currently in a void above the refrigerator. If I go to higher power -that is probably not the best place for it (it was chosen by manuf. because it is right under the roof cap.) So a new charge controller should probably go in a storage bay that is right next to the battery compartment - meaning the run from the roof to the controller will be longer - which would make me lean towards higher voltage.
2) Charge controller. This is an attempt at a (somewhat) budget build. Would like to not blow the bank on the charge controller and am willing to compromise on specs of it means substantial cost avoidance. That includes dropping down from 600W to 500 or even 400. I do have a generator after all - and if I replace the converter/charger with a higher amp output, I can always squeeze power back into the batteries while I run the air conditioner off the geny. Basically - looking at managing total project cost including panels,MPPT, and possibly converter/charter.
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