Zener Diodes

Answer: You don't . You use Schottky diodes. [ low Vf drop ]




Here is how a BLOCKING diode (only 1 per string needed, and most often, this function is incorporated in charge controllers.


For a BYPASS (when cells shut off from shade) diode, you need to install one about every 6 volts worth of cells.

of course, the trade off is, each diode you install, consumes about .75V


Diodes only help steer voltage around shaded panels (bypass) or prevent nightime backfeed from the battery (only 1 dioded needed per string) Most charge controllers provide the nightime backfeed isolation, so a proper, unshaded system needs no diodes.

Zener diodes are simple voltage regulator or voltage clamp.