Charging a battery with a PWM Charge controllers solar system is a unique and difficult challenge. The history for on-off regulators has been early battery failures. Increasing load disconnects, and growing user dissatisfaction. PWM controllers has recently surfaced as the first significant advance in solar battery charging.
PWM Charge controllers use technology similar to other modern high-quality battery chargers. When a battery voltage reaches the regulation setpoint. The PWM controllers programming slowly reduces the charging current. This is to avoid heating and gassing of the battery. Charging continues to return the maximum amount of energy to the battery in the shortest time. The result is a higher charging efficiency, rapid recharging, and a healthy battery at full capacity
In addition, this new method of solar battery charging promises some very interesting and unique benefits from the PWM pulsing. These include:
Ability to recover lost battery capacity and desulfate a battery.
Dramatically increase the charge acceptance of the battery.
Maintain high average battery capacities (90% to 95%) compared to on-off regulated state-of- charge levels that are typically 55% to 60%.
Equalize drifting battery
Reduce battery heating and
Automatically adjust for battery
Self-regulate for voltage drops and temperature effects in solar
How does the PWM Charge controllers benefits the solar system user?
Longer battery life:
Reducing the costs of the solar system
Reducing battery disposal problems
2. More battery reserve capacity:
Increasing the reliability of the solar system.
Reducing load disconnects.
Opportunity to reduce battery size to lower the system cost.
3. Greater use of the solar array energy:
Get 20% to 30% more energy from your solar panels for charging.
Stop wasting the solar energy when the battery is only 50% charged.
Opportunity to reduce the size of the solar array to save costs.
4. Greater user satisfaction:
Get more power when you need it for less money!!..
Buyer be aware! Many solar charge controllers that simply switch FETs. It is differently than the on-off algorithm claim to be a PWM charger. Only a few controllers are actually using a Pulse Width Modulated (PWM) constant voltage charging algorithm. The rest are switching FETs with various algorithms that are cheaper and less effective.