Hello everybody

I have designed a PCB for the company i work for which is used on an
automatic machine..
The board has 3 PICs on it (2 16C54 and 1 16C55)

This board interfaces with 3 external power relays.These relays are
signaled from 3 other reed relays on the board which are
opto-isolated from the signaling PIC.

When the power relays operate alone (not connected to the machine's
motor) there is no problem. But when they are connected problems
start. These three relays control a two speed bi-directional  220V
motor. At the change of speed or direction the electronic circuit
seems to be reset (it happens about once in 10 changes).

Can anyone tell me what is happening ?


Harry