I have an ignition system used for some application.
During the testing I found that spark plug is producing EMI due to spark occurrence and high voltage is traveling through the wire.
So to suppress the noise signals, I connected the secondary end connection to the earth (through electrical junction box.) But when I turned on the setup, the equipment (RPS) which connected on the same line (connected on the same junction box) is disturbed (glitches in display,) within few seconds RPS is blown off (something is burned inside the RPS).
I am not able find the exact problem but during the testing I tried moving the earth connection near to the secondary end, suddenly an arc is jumped from secondary end to earth connection.