holabr
Member level 2
I need a circuit that will close a relay (to sound an alarm) when the voltage in a 24 volt battery (2 - 12 volts in series) drops to a predetermined voltage. I'd like to be able to adjust the threshold voltage. I also plan to add a timing circuit to sound the alarm for a defined period of time. This is to remind me to plug in a battery charger on a handicap wheelchair that doesn't get used very often. The manufacturer recommends not leaving it on charge but only recharge when the voltage drops at least 1/4 full charge. Any ideas or examples to start me down the road?