Hi - I have built a circuit to reverse the direction of a DC motor. The motor is 12 VDC and draws a max of 42 mA and the windings have a resistance of 17.2 Ω. My relay is a DPDT dual 5 VDC latching relay rated at 1 amp DC. The motor rotates a wheel which eventually actuates a NO limit switch. The closure of this switch allows current to flow to one of the coils in the relay which switches the contacts in the relay such that the voltage to the motor changes polatity and the motor moves the wheel in the opposite direction until it actuates another NO limit switch which allows current to flow to the other coil. This shifts the contacts back to the original position reversing the voltage polarity to the motor which causes it to reverse and move the wheel back in the other direction. I am aware that putting an RC circuit across the contacts will help prevent them from arcing due to the abrupt halt of the current flow through them. I am trying to get an idea for the values of the capacitor and resistor that would best serve this function and still be very cost effective. So far I thought that a non-polarized mica capacitor of .01 µf value rated a 150 V and a 1/2 watt 47 Ω carbon resistor in series across each contact would do the job. BTW, I know this is not an ideal situation. Turning off the current first and the switcing the contacts would be a better way to do this. However until I can get around to re-designing the circuit, I am looking for a stop gap measure to protect what I now have running. I would welcome any comments pro or con.