hwy17
Anti-Solar Enthusiast
I am working with an XW+, MPPT 100 600, 3.8kw array (not yet built), grid input available, and 24-60kw daily consumption. Battery bank will be 15kwh to start and then grow.
For reasons partially justified and partially irrational I am considering breaking the system out into double conversion. With all loads running off the XW+ from DC all the time, like an off grid system, and utility power only coming in via a chargeverter.
This concept would require a lot more manual tinkering and customized automation of the charging logic.
The charger could come on via relay trigger from the Schneider system, relay trigger from the BMS, a timer, or a combination of those.
However, I don't want the charger to kick on at 1am or whatever and fully charge the bank from utility, leaving too little room to absorb the next days solar production.
This would all be a lot easier if the chargeverter could maintain the bank at 20% and variably provide charging below that without charging to above that.
Does it work that way? Say if I set charging voltage to 51.2 or 51.6 or something around there, would it put variable amps into the bank depending on the load below that charge state, and then when the load is removed would it taper off amperage as the bank comes back up to 51.6, effectively holding the bank at 20%?
Also, importantly, if solar brings the bank up above that to 54-58v, would a chargeverter set to 51.6 happily sit their idle against the 58v bank, waiting for it to drop below 51.6?
Maybe it would need to be 52 or something, but you get the idea.
If it does work this way I could almost not require any charger relay logic at all. Charger could be enabled all the time as a backstop power supply.
(note: I realize this could cause some balancing problems over time depending on solar charging, and I could do manual full charges once in a while to top balance)
For reasons partially justified and partially irrational I am considering breaking the system out into double conversion. With all loads running off the XW+ from DC all the time, like an off grid system, and utility power only coming in via a chargeverter.
This concept would require a lot more manual tinkering and customized automation of the charging logic.
The charger could come on via relay trigger from the Schneider system, relay trigger from the BMS, a timer, or a combination of those.
However, I don't want the charger to kick on at 1am or whatever and fully charge the bank from utility, leaving too little room to absorb the next days solar production.
This would all be a lot easier if the chargeverter could maintain the bank at 20% and variably provide charging below that without charging to above that.
Does it work that way? Say if I set charging voltage to 51.2 or 51.6 or something around there, would it put variable amps into the bank depending on the load below that charge state, and then when the load is removed would it taper off amperage as the bank comes back up to 51.6, effectively holding the bank at 20%?
Also, importantly, if solar brings the bank up above that to 54-58v, would a chargeverter set to 51.6 happily sit their idle against the 58v bank, waiting for it to drop below 51.6?
Maybe it would need to be 52 or something, but you get the idea.
If it does work this way I could almost not require any charger relay logic at all. Charger could be enabled all the time as a backstop power supply.
(note: I realize this could cause some balancing problems over time depending on solar charging, and I could do manual full charges once in a while to top balance)
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