grimjordax
New Member
This is my latest project I just completed. It is a multi-channel lead acid battery charger. It can be used for VRLA, gell cell and wet cell types. It is designed to charge battery jars with a nominal voltage between 4 and 12 volts. It will also work well with any battery type requiring a constant voltage float charge. It has built in limiting circuitry to keep each channel at or below 1.25 amps. The individual channels may be paralleled for higher current. Once the set voltage is adjusted and the channel is turned on, the charger will try to drive to the set voltage while automatically current limiting. As the set voltage is reached the current diminishes to a fractional amount that is required to "float" the battery at that setpoint. The system has automatic fault detection for over/undervoltage and battery disconnect as well as open cell detection and will automatically turn off the affected channel.
The charger is built around a modular approach whereby the charger cicuitry is on small charger PCBs that connect to a main 24V supply and are driven via a PWM signal from a microcontroller. They also provide a voltage feedback to the microcontroller via ADC input. A 4x20 matrix serial lcd screen and 4 membrane type buttons are used for HMI. The microcontroller used is a Picaxe 20M2 mounted on a Kiwi Patch board. The power supply is by Mean Well and there is a cooling fan mounted left side to keep everything running cool.
nutsandbots.blogspot.com
The charger is built around a modular approach whereby the charger cicuitry is on small charger PCBs that connect to a main 24V supply and are driven via a PWM signal from a microcontroller. They also provide a voltage feedback to the microcontroller via ADC input. A 4x20 matrix serial lcd screen and 4 membrane type buttons are used for HMI. The microcontroller used is a Picaxe 20M2 mounted on a Kiwi Patch board. The power supply is by Mean Well and there is a cooling fan mounted left side to keep everything running cool.
nutsandbots.blogspot.com