More Solar for "Us"
Ok, I went off.the deep end? Bought 3 used 37watt uni-solar panels and a blue sky 2000e controller for the hefty price of $400, They were being listed as 75w panels, they are not The tested open...
Forum Discussion
Setpoint has everything to do with the MPPT efficiency. First off, the controller doesn't know the voltage of the battery. It calculates the most efficient power point by using the voltage at the output of the controller, not battery voltage. There is no battery sense line.
There are a few bad things happening with a high setpoint.
1. The higher the setpoint, the smaller the difference between controller input and output voltage. You've now eliminated the advantage of MPPT. MPPT wants to see a large voltage difference between input and output.
2. The higher the converter output voltage the lower the charging current.
3. Gassing increases. Battery overcharging.
BTW Jim, you better read the Blue Sky manual before giving false information.
Sal
There are a few bad things happening with a high setpoint.
1. The higher the setpoint, the smaller the difference between controller input and output voltage. You've now eliminated the advantage of MPPT. MPPT wants to see a large voltage difference between input and output.
2. The higher the converter output voltage the lower the charging current.
3. Gassing increases. Battery overcharging.
BTW Jim, you better read the Blue Sky manual before giving false information.
Sal
bigfootford wrote:
Mppt is a function/feature that a controller does and has nothing to do with the setpoint.
If a controller has the setpoint feature then when the setpoint voltage is met which is the output of the controller to the battery then the controller will revert to the absorb voltage which is lower than setpoint. The Absorb voltage is usually low enough to stop gassing.
Jim
