need help building a relay on delay circuit

[puckhead]

i have a relay that in normal operation is energized. during a machine reset, it is momentarily de-energized by another relay. i need to slightly delay( about 1/2 second to 1 second) the re-energizing of the relay. it is an 80 ohm coil, powered by 50 V AC ( 60 hz) .
i was thinking a diode to change it to DC, then a charging cap, but i have no idea how to implement that, or if it would even work. any ideas on a simple circuit are most welcome. FYI, its an old electro-mechanical arcade game.

thanks

 

[crutschow]

A diode and a capacitor to ground could work but it would need to be a large capacitor (about 10,000µF). You could add a transistor to drive the relay which would allow the use of a much smaller cap. For example using a MOSFET, you could use a 10µF capacitor with 100kΩ impedance at the gate to give about the same delay.

Also if you operate the relay from DC you would likely need a resistor in series to reduce the current, since the normal relay coil inductance would no longer be limiting the current. To determine the value of the resistor needed, measure the AC current of the relay. Then add a resistor in series with the DC resistance of the relay coil to give the same current with the DC (which will be about 70VDC for the rectified 50VAC).