Battery bank issues
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MisterSandals
Participation Medalist
Sure you can. But if you don't connect them in a balanced manner, they become, uh, unbalanced over time.
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Bob B
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I personally would err on the side of safety and would also make sure the battery voltages are as close as possible when parallel connecting them.
Arcs and sparks can happen when connecting high current devices together ..... It probably won't cause a problem with the SCC, but I would disconnect it anyway.
If you aren't set up with an easy disconnect method on both sides of the SCC .... this would be a good time to do that.
Arcs and sparks can happen when connecting high current devices together ..... It probably won't cause a problem with the SCC, but I would disconnect it anyway.
If you aren't set up with an easy disconnect method on both sides of the SCC .... this would be a good time to do that.
MisterSandals
Participation Medalist
This is a far better answer than mine. Safety glasses are a must.
You'll want to rewire your entire battery bank so having all the charging and loads disconnected need to be done anyway.
Bob B
Emperor Of Solar
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Well ..... Yeah, you could .... but then you are getting into natural selection territory. LOL
Yes but no.
Yes as in you can.
No as in... remember when 1st set things up? Rule = connect battery to solar charge controller 1st. Why = so controller sees voltage it will be regulating.
Understand why u would not want to alter ur battery bank without 1st disconnecting? Its not about safety. Its about your system operating as designed.
Alphacarina
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If the batteries are all the same type and voltage and the same age, then sure - I wouldn't be connecting some new batteries I've just bought in with my bank of 3 or 4 year old batteries . . . . especially if we're talking lead acid batteries
Don
OffGridInTheCity
Solar Wizard
Over the years, I've added 4 separate 14s100p 'additional' batteries to my powerwall. As part of the battery build process, I bring each pack down to 3.6v with my iCharger X8 so that when I put them in series - they are all pretty much 3.6v (+/- 0.05v) which happens to be the typical morning voltage of the overall battery bank.
This let's me chose a morning of my liking (no special action required) and hook it in because voltages are close enough to the main powerwall to avoid any amp surging. Once in place, I use the Batrium auto-level feature to fine-tune the balance with the other packs.
This point I want to make - you can extend the battery creation process to include safe installation as the last portion of the process.
This let's me chose a morning of my liking (no special action required) and hook it in because voltages are close enough to the main powerwall to avoid any amp surging. Once in place, I use the Batrium auto-level feature to fine-tune the balance with the other packs.
This point I want to make - you can extend the battery creation process to include safe installation as the last portion of the process.
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Interesting... I thought swapping out an older battery for new one (same type etc) was fine.
Are u saying its ok to add an additional string as long as batteries r same, including same age and/or performance level?
I still say no because of the initial need for the controller to calculate output voltage regulation (what its gonna need) before seeing input (panel voltage).
Just going by the way a solar system works. Makes sense to add string then turn SCC back on (actually to be safe, disconnect panels from SCC, add batt string, re-attach panels).
Wrong or right, thats what I'd do. Wont hurt anything and assured functioning correctly.
Alphacarina
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Swapping out an older battery for a new one is fine - Paralleling a new one with an older one may lead to problems
Don
