Any easy circuits to be made to handle adjustable low voltage cutoff for a pack discharger?
And on a similar note, an adjustable max voltage cutout for charging?
Bonus points for a cicuit that does both
you start out with a relay in the current carrying line for both configurations of low and high cutoff. then you cut off power to the relay coil when the voltage drops below or rises above the limit.
if you want to get fancy choose a relay with multiple contacts so one set can be used to latch the relay on. if you do not do this the relay can just be on any time the voltage is inside the operating range. with a latching configuration you have a pushbutton start and an automatic cutoff.
i know i have described this idea somewhere else, but my short term memory is not what it once was, and i forget where. if this explanation is not enough i could draw a schematic if you give me the desired setpoint range.
for low voltage cutoff, you could keep the relay coil energized with an npn transistor that was kept turned on by a voltage divider off the battery voltage, set so that when the voltage drops to the preset cutoff point the transistor turns off and the coil opens.
for the high voltage cutoff, you could use a second transistor that steals away the base current that keeps the first one turned on when the second transistor is turned on by its voltage divider. this will work better with the latching configuration, since that will prevent the coil from being re-energized once the trigger point has been achieved.
a combination of zeners or 3 terminal regulators with the resistor network will make the results more reproducible.
I do not approve of this group any longer and regret what it has become. I could once share ideas here freely that is no longer possible.