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Relay Circuit Design

Relay Circuit Design

Relay Circuit Design

(OP)
I have a relay circuit which uses 3 power relays to control two AC motors and one AC light load.  The relays are switched through a 12V signal from a darlington array ic.  The two motors are alternating one on, one off every three minutes and the light load is continuously on.  

The problem I am having is that the relay controlling the light will unexpectedly turn off after about 10 minutes of cycling the motors.  I have 100uF caps on the relay coil lines but the light relay still looses contact.  

Any suggestion on where to start troubleshooting, power supply issue (30mA each through 7812 v-reg), capacitance, etc?

thanks

RE: Relay Circuit Design

send schematics

<nbucska@pcperipherals DOT com> subj: eng-tips

RE: Relay Circuit Design

Does it come back on after dropping out? If not, how do you get it to start working again?

"Venditori de oleum-vipera non vigere excordis populi"


RE: Relay Circuit Design

have you found the problem?

<nbucska@pcperipherals DOT com> subj: eng-tips

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