what is zero drop pwm charge controller

solarking

what is zero drop pwm charge controller ? Is there any difference between the zero drop pwm vs pwm charge controller?

BB.

Not much.

Mechanical relays have zero resistance and zero volt drop. Of course, mechanical relays have shorter life of they are cycled many times a minute for own voltage/current control while charging the battery.

Depending on the specific transistor type, dune some may have more resistance and more voltage drop than others. More voltage drop means more heat to dissipate, and larger heat sinks. Also, more voltage drop between the solar panel and battery bank means a bit less power/current with hot panels (low Vmp) and cold batteries (higher charging voltage).

A better pwm controller will be designed to keep voltage drop low, add well as the installer to use large diameter and short copper cable. But that does make for higher costs.

Everything has tradeoffs.

- Bill