There are times when I wonder at people's thought processes... specifically, IF there are any.
Ok, so I've built a solar powered lighting system for my workshop. Two panels providing a total of 50watts, and a 12volt 7.2 Amp/hour battery all hooked up via a charge controller and a twilight switch over sensor. [so the lights come on automatically in the dark]
Relatively simple... except it's not. The charge controller is microprocessor controlled and has a number of bells and whistles, extraneous features to the basic function of something that takes power form the solar panels and charges the battery, while maintaining a constant voltage output to the load. [lights].
And that's where the problem is. The charge controller requires power to work.
At some point in it's design process, a decision was made that the charge controller would ONLY
draw power from the battery. Thus, if the battery runs flat[ish] and the voltage falls below a critical point, the charge controller stops working... and will not turn back on even if the solar panels are generating power.
In other words, someone built a battery charger, that doesn't work unless
the battery is already [partly] charged.
I'm going to have to build a by-pass, something that will provide a trickle of current via a blocking diode directly to the battery terminals from the smaller 10watt panel. Just so the system will jump-start should it run flat.
Crossposted from: http://siliconshaman.dreamwidth.org/1231
comments so far over there.