Instruction manual

10
4 Operation
4.1 PWM Technology (Series Pulse Width Modulation)
The controller adopts the advanced series pulse width modulation. With range of 0-100%,
it can charge the battery quickly and stably under any condition of solar photovoltaic
system.
The operating principle of PWM charging mode is as follows:
The battery is firstly charged with pulse current and recharged after it stops charging for a
while. It is repeated in this way for several times till the battery is fully charged.
Intermissions allow some oxygen and hydrogen generated by chemical reaction can be
chemically combined again and then absorbed, which can eliminate concentration
polarization and ohm polarization naturally, and reduce the internal pressure of the
battery. Consequently, it makes next charging smooth and the more power is charged to
the battery. Intermittent pulse current charging mode makes battery have more time to
react, which reduces the gassing volume and makes battery improve the acceptance rate
of charging current.
4.2 Battery Charging Information
Figure 4-1 PWM Charging mode
·Bulk Charge
In this stage, the battery voltage has not yet reached boost voltage and 100% of available
solar power is used to charge the battery.