Projects/Access Control/Power

The Access control system is mains powered through a laptop power supply. Battery backup is incorporated with a gel lead acid battery. Outputs are provided for the Raspberry Pi ( 5V USB connector), and 13.8V for the Door lock. Monitoring of the battery and supply voltages is possible from the interface card. Laptop Power supply can be any power supply providing around 18 to 20V at 1 A.

13.8V and 5V regulators are these:



Battery charger board is this:

Regulator is adjusted for 13.7V output, charge current = 300mA There are diodes to combine the battery and 13.8V regulator outputs. Also diodes on inputs to Battery and 13.8V regulators. The 3 pin connector is the voltage monitor to the ADC on the interface board.