Thankyou Sir;

It seams to be a similar problem, when I change the SMPS or move the SMPS away from the prototype connected with wire the problem doesn’t occur.

I am working on my SMPS....

As my validation proceeded with another SMPS I noticed that there was no problem on operation even when placed near two 230V operated contactors. But when I operate them through my relay my system is getting reset. I.e. when the 230V to the contactor is switched through the relay.

I thought it would be a problem with the layout, so i cut the tracks and then connected the relay with thick wires, but still it happens.

I am using a 96*48*150mm module, where I have two layers of PCB placed the lower layer has SMPS, Relay and serial comm. Circuitry.
The upper layer card has the signal conditioner CPU and a retransmission Output Circuitry. The distance between the upper and the lower layer PCB is 22.2mm, connected with burge connectors.

Is it that the disturbance generated while switching of the relay is effecting the controller above it.....? What can be done in this case.....? I tried keeping the upper PCB aside connected through wires but still it resets on switching of the relay with 230V line to the contactor.

If the relay is switched without the 230V supply on the relay there is no problem at all...

Waiting for reply....
Jayachandran Nair...