Other uses for the Solar Controller Kit

[Don Brown-4]

Hi

Tom Hammond suggested I mention that my solar controller does not really
need a solar panel to work as a battery charge controller. Any power supply
that can be current limited in the 16 to 24 volt range can be used as well.
A 18 volt transformer, rectifier and filter cap and large limiting resistor
will work.

To figure the limiting resistor use ohms law to get the value. For example
for 2 amps charging current and a 20 volt power supply subtract 11 volts for
the discharged battery voltage from the power supply voltage. That is 9
volts divided by 2 amps is 4.5 ohms. To get the power rating for the
resistor square the voltage drop that equals 81 and divide by the resistance
4.5 ohms that equals 18 watts. Add some margin to the resistor for safety
and a 2 amp fuse to protect the power supply in case the battery should have
a shorted cell or other defect. I would use a 20-25 watt resistor. You can
use this power supply or a solar panel to charge the battery with the
controller depending on your needs. The controller can be mounted in your
battery box and either the power supply or solar panel can plug into the
controller.

Thanks

Don Brown
KD5NDB
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