6545 Hexapole 2 RF Fault

Hi Stacy, any luck finding an answer to this question?

Hi Richard, yes I had finally called in for service. The service engineer looked at the part, and a test was done to set it to 0 V and then ramp up the voltage. I am not sure if any adjustment had been made or just a reset. Anyhow, the issue was cleared without needing new parts.

It was mentioned that it may have been caused by temperature sensitivity. Our lab had experienced temperature swings because the AC had been turned off (temperature was getting around 29 or 30 C), and it was several months until our building facilities repaired it to get back to normal (around 21 C). Sometime after the service engineer corrected the issue, we had an AC problem again where the lab temperature went to around 26 C, and the Hex2 RF fault started showing again. The problem went away when the AC was fixed.

Very interesting! Thanks!

Just wanted to add that this was a very useful post! We have an Agilent 6530 QTOF in a warmer-than-ideal room and it was giving a similar, though not the same, RF voltage fault (in our case it was a "Rear Octapole RF fault" and even at some point gave the dreaded "Medusa pusher voltage fault" and "Medusa puller voltage fault" errors). Based on the idea from the above post, I noticed that some ventilation holes on the outside of the electronics box toward the back right side of the instrument, were a bit clogged with dust.  We vented and powered down the instrument, removed the right exterior panel, and carefully brushed the dust away from the vent holes with a cloth (we did NOT open the actual electronics box and were careful not to push dust inside the holes).  After powering back up and pumping down, the system went to ready state and the errors have yet to recur after leaving the instrument overnight with mobile phase flowing to the source and all voltages and temperatures ON. Time will tell if the trouble is gone for good without permanent damage, but just confirming that inadequate cooling could be a possible culprit if you see voltage faults! 

Glad to hear, and thanks for adding the tips about the ventilation holes! I should probably check that on our instrument too....

Great to hear! I forgot to leave an update - there had been an issue with the buildings heat where the lab was really excessively warm just by coincidence when we were trying to start it back up. We left it running for a few days and once the lab had cooled back down to a reasonable temperature, it fixed itself. It has also been off and vented for a week or so while we were doing maintenance, so I'm not sure if that played a role or not, but since it was all coming up from ambient with different parts are all generating different amounts of heat, as well as the fact that it's under vacuum so things can't warm up evenly by convection, I wouldn't be surprised if it was at least a factor. The error disappeared very soon after the temperatures and pressures finally reached their normal operating equilibrium. 

I wouldn't have guessed the electronics are SO sensitive to temperature that a few degrees higher than normal is enough to knock them off line, although I suppose it makes sense in retrospect considering how spectacularly tiny the signals its measuring are and how much amplification is required. 

Great to hear! I forgot to leave an update - there had been an issue with the buildings heat where the lab was really excessively warm just by coincidence when we were trying to start it back up. We left it running for a few days and once the lab had cooled back down to a reasonable temperature, it fixed itself. It has also been off and vented for a week or so while we were doing maintenance, so I'm not sure if that played a role or not, but since it was all coming up from ambient with different parts are all generating different amounts of heat, as well as the fact that it's under vacuum so things can't warm up evenly by convection, I wouldn't be surprised if it was at least a factor. The error disappeared very soon after the temperatures and pressures finally reached their normal operating equilibrium. 

I wouldn't have guessed the electronics are SO sensitive to temperature that a few degrees higher than normal is enough to knock them off line, although I suppose it makes sense in retrospect considering how spectacularly tiny the signals its measuring are and how much amplification is required.