help with emf protction of timer module

Discussion in 'General Electronics Chat' started by psknight, Jun 7, 2012.

  1. psknight

    Thread Starter New Member

    Jun 7, 2012
    Hi All

    Need help with a circuit diagram back emf protection of a timer module, relay and 24v shut down solenoid. I am using 3 wire shut down solenoid. switching hold in winding from a on / off switch and switching power to a timer module to switch earth to a relay to feed the pull in winding for 2 seconds. however i think backemf from the pull in winding is damaging my timer module. what is the best way to solve this problem. Thanks for the help in advance

    cheers Peter
  2. crutschow


    Mar 14, 2008
    Do you have a diode across all solenoid and relay coil windings (diode cathode to plus side of winding) to suppress the solenoid kickback voltage? If not, you need to add that.