We have a 7800 ICPMS and was working fine until this morning I switched the plasma on and it went on then off in a couple of seconds.
The RefPower goes up from 0 to about 170 and the Forward power up to 1198 then it switched off.
I removed the shield plate: RefPower went up to 209, Forward power went up to 1198 again and switched off.
I put the shield plate back on: RefPower moved from 0,110,484,2268,167,0. Forward power moved 0,749,200,181,0 then it switched off.