operate or pull in current but greatly reduces the amount of force required to return the armature to the open position previous coin relay designs provided a shirt circuit across the coil after the relay is closed which increases the time required for the magnetic field to collapse thereby delaying the return of the armature 3 to the open position the thickness of the material used for the magnetic shield controls the amount of hold current required for operation of the coin relay contacts of switch 8 provide an indication to the microcomputer of fig3 or other controlling device when the relay is closed thus switch 8 can be used to indicate when the relay is stuck in closed or if necessary for timing the relay referring now to fig2 the right side of the relay is shown of particular interest is bar magnet 12 attached to selector card 11 the center pole piece 10 for the relay core 2 is positioned over the bar magnet 12 when the relay operates the rocker arm 13 forces the selector card down the bar magnet 12 then forces the selector card to tilt to the left or right depending on the polarity of current through relay coil 1 slots 15 and 16 in.