BFL13 wrote:
The fear of controller-battery voltage drop is that it will not let the batteries reach the controller's high set point, so the batteries will be undercharged.
If amps have tapered by then, the voltage drop will be less anyway, as Almot mentioned. Regardless of that, you can just raise the high set point to allow for the drop so as to get the batteries up where you want for Vabs. . . . . . . .
That is exactly my problem. 25 feet or more of #6 from the controller output to the 4 GCs causes a full volt drop at 20A. This means that the controller "sees" 14.8 Volts at the battery while the true battery voltage is only 13.8V. The controller then reduces the charge. As the charge current decreases the voltage drop also decreases, and if the sunlight lasts long enough the battery will eventually reach 14.6V, sometimes all the way to 14.8V but not for long.
