Battery monitor

Lead acid batteries can be damaged if the voltage is too low for a long time. To know when the batteries needs charging, you can use a battery monitor. The Battery Monitor is designed for 12V battery voltage, and the device is sensing the battery voltage via the input cables. Green LED means that the battery voltage is normal. The Battery Monitor can also control external devices / indicators (eg. Relay) which can display the battery level. When everything is OK, the battery monitor drives current through the external equipment, (sink, via Out4 and / or Out3). When the battery voltage decreases, LED goes from Green to Orange. Out4 goes from Low (sink, means conducting current) to "Open Collector", (not conducting current). When the battery voltage decreases even more, LED goes from Orange to Red. Out3 goes from Low (sink) to "Open Collector". When the battery voltage rises again, the LED goes from Red to Orange and finally to Green. Out3 and Out4 go from "Open Collector" to Low (sink) again, but it is a hysteresis at ca. 0.2 V.