Main Suppression not effective ..

Hi,

The pic below shows a block diagram on my pic controller.

The pic is on a separate board to all the power components, yet over night the Pic is being reset many times by what I conclude is mains interference. ( I have a software Resets counter )

The design ran alongside my old controller, ( no relays connected to loads ) for several weeks without any resets, but once the heater was connected to it the problems started.


Changing the heater and relay made little difference, but last night I fed the whole DC side from a car battery and I only had 2 Resets, so this tends to imply its interference on the power lines.

I am using the filters shown so am a bit lost as to what else I can do to reduce this interference.

Any help appreciated.

As you've only posted a vague block diagram how are we supposed to help?, post the FULL and EXACT circuit diagram and we can probably help, don't leave out any of the components on the diagram.