Solar panel/ DC motors

[craig65]

i have a 12 volt motor and a 20 volt solar panel, I know with high voltage a 70% overage in voltage will fry a motor I assume the same would be true for any motor. There is no range on the name plate, just says 12 volt.
Will an under/over voltage burn up a 12 volt DC motor?

 

[gar]

090908-0756 EST

To a major extent two factors determine maximum applied voltage to a permanent magnet DC motor. These are internal breakdown voltage and power dissipation. I will add a third, mechanical speed limitations.

Voltage breakdown is related to the insulation and maximum transient voltages. On a low voltage motor breakdown voltage is not likely a problem.

Power dissipation is largely a current problem, and this is load related. But in turn this could mean speed related.

A PM DC motor speed is proportional to applied armature voltage. Double the applied voltage and it approximately doubles the speed. Under no load this is no problem.

Keep in mind that a photovoltaic cell after a certain load current is approximately a constant current source.

,

 

[LarryFine]

Keep in mind that a photovoltaic cell after a certain load current is approximately a constant current source.

Meaning that the panel output under load will likely be nowhere near 20v.

I suggest a short-duration experiment, and read the voltage with the motor.