ZEI Solar Optimizers accomplish three things:
1) Voltage Step Up- When using a battery or storage cell there is a natural power peak at full sun exposure which falls off as the sun sets or is obscured when these charging conditions change the optimizer manages the voltage profile to maximize energy storage.
2) Battery Charging- If the battery is a 24vdc lead acid, the charging voltage of 28.8vdc is set with an on-board potentiometer (pot). The pot is adjustable between 22.0 and 37.0vdc. If the pot is set at 28.8vdc (typical charging voltage for a 24V battery) and this voltage is exceeded then no charging current will flow. When the temperature compensated voltage of the battery is within the appropriate range which is set by the pot the battery is charged. The optimizer is powered by the PV panels not the battery so there is no "leakage".
3) Power Optimization- Solid state electronic circuitry monitors power every 0.5s. The pulse width modulation is changed, if needed, every 0.5 seconds. At low powers, when the sun is low in the sky, every watt of power is transferred to the battery. One watt produces 0.025 amps at of charging current @40vdc. At midday power output can reach 200 watts which will produce 5.0 amps of battery charging current.