Of course there is an 8051 derivative providing the signals. I need to control 4 relays, 3 of which are just contact closures for a PLC to read the status of. The fourth relay needs to control a 24VDC gearmotor.

I've built a small point to point PCB for the relays, TPIC, and LED's. Power comes from the main PCB.
This is a partial circuit not showing all of the relays, the LED's are for visual monitoring. The relays are a 5V coil with 125 ohms coil resistance = 40 mA coil current. The TPIC says it can sink 100 mA/per output. It also includes fly-backs.


I've used the following circuit triggered by the closing of the fourth relay to turn on the primary winding of a 24VAC transformer, the output is bridge recitified, filtered by a 2200uf electrolytic,with a fly-back, that supplies power for the gearmotor.


I've tried a few different schemes and this one had the least glitches.

THE PROBLEM:

At times the relays don't hold, their state, it happens mostly when the gear motor turns on or off. I've tried a reserve 330 uF electrolytic on the relay board power input, additional fly-backs on the coils of the relays. Maybe the snubber on the triac circuit is not appropriate for the transformer? I don't see any glitches on the scope when the gear motor turns on and off? Can I drive relays directly with TPIC?
Thanks
Jon