I have one pnp and LDR based switch to control a relay for a motor to run in the evening. Two npn based transistor switches, each one is for controlling the same relay if certain conditions are met for two water tanks. One would be driven by output of 555 by two inputs to it from upper tank and other is for the motor to work only if there is enough water in the lower tank. It is desired that relay will get activated (deactivated) when required conditions are met ( any one is not met). These therefore need to be 'in series'. These three are working fine individually on the breadboard. I am unable to connect these to the relay coil in series. Is my information (writing included) enough for an expert to suggest how these be connected so that if any requirement is not met the motor wouldn't 'run' ? Many thanks in advance to helping nature Samaritans on the forum.
S R Paranjape
S R Paranjape