Forum Discussion
Salvo
Nov 18, 2014Explorer
Proof is in a test.
MPPT controller output current is: I = Psolar / Vbat
That means, the lower Vbat the greater the charging current. A pwm controller outputs constant charging current, regardless of Vbat.
The OP just needs to record charging current at different battery voltages while the controller is in bulk charging mode.
If absorption voltage setting is 14.7V, then record current when Vbat = 14.6V. Now connect inverter and drop Vbat to 12.6V. You should be able to drop voltage in a few minutes. We're just dealing primarily with surface charge.
If it's a mppt controller (and solar outputs 100W) then current will change from 100W/14.6V = 6.85A to 100W/12.6 = 7.94A.
You should see about 1A swing with mppt and no difference with pwm.
MPPT controller output current is: I = Psolar / Vbat
That means, the lower Vbat the greater the charging current. A pwm controller outputs constant charging current, regardless of Vbat.
The OP just needs to record charging current at different battery voltages while the controller is in bulk charging mode.
If absorption voltage setting is 14.7V, then record current when Vbat = 14.6V. Now connect inverter and drop Vbat to 12.6V. You should be able to drop voltage in a few minutes. We're just dealing primarily with surface charge.
If it's a mppt controller (and solar outputs 100W) then current will change from 100W/14.6V = 6.85A to 100W/12.6 = 7.94A.
You should see about 1A swing with mppt and no difference with pwm.
Bend wrote:
Seems no coil therefore no MPPT:
https://www.youtube.com/watch?feature=player_embedded&v=KA3X8XLxWHU
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