Skip to main content

Posts

Showing posts with the label Battery Level Indicator

Battery Level Indicator 36 Volts Schematic Circuit

Battery Level Indicator 36 Volts Schematic Circuit

This battery level indicator offers (5) LEDs that light up progressively as the battery voltage increases. This is a update of the 24V Battery Level Indicator.
While designed for 36V systems, it is easily modified to 24V, 48V or 60V simply by changing two resistors.
LED ColorCharge LevelRed:Power Connected (0%) (essentially always on)Orange:Greater than 35V (25%)Yellow:Greater than 37V (50%)Green:Greater than 39V (75%)Blue:Greater than 41V (100%) (full charge is about 41 to 42V) Of course, you may select your own colors if desired.
High voltage issues One limiting factor is the LM339 that has an absolute maximum voltage rating of 36V –and it is not good practice to operate near that point. The solution involves running the IC power rail off a zener shunt regulator. Shunt regulators are very simple, inexpensive and robust –good for this application. However, the LM339 open collector outputs cannot drive LEDs powered from the battery bus d…