Advertisement

Agilent/HP MSD Quad DC Fault

Discussions about GC-MS, LC-MS, LC-FTIR, and other "coupled" analytical techniques.

2 posts Page 1 of 1
I'm looking for technical help with an Agilent/HP 1946D MSD. Here's what's happening:

- if i try to do an autotune it comes up with "difficulty with ion
optics electronics - Quad DC fault"
- it fails all points of the MSD ion optics test giving "quad DC fault"
for each of the failures
-it fails the MS Quad electronics test on the RF drive scan part, the
chart is spikey instead of a straight line
-the machine is powered up and otherwise functional.

With all that information, what do you think whats wrong? Any suggestions are greatly appreciated!

John
I'm looking for technical help with an Agilent/HP 1946D MSD. Here's what's happening:

- if i try to do an autotune it comes up with "difficulty with ion
optics electronics - Quad DC fault"
- it fails all points of the MSD ion optics test giving "quad DC fault"
for each of the failures
-it fails the MS Quad electronics test on the RF drive scan part, the
chart is spikey instead of a straight line
-the machine is powered up and otherwise functional.

With all that information, what do you think whats wrong? Any suggestions are greatly appreciated!

John
It could be several things. The first thing I check on any sort of power or electronics fault is making sure all the connections are good. I have had our 5973 MS lose connection where the pins from the quad attach to the side board. Cleaning the pins and re-assembling does the trick. If all the connections are good, and there is no physical damage to the quad,then you are most likely looking at a bad board or power supply. I have not worked on a 1946 so I can't really give specifics.
2 posts Page 1 of 1

Who is online

In total there are 41 users online :: 3 registered, 0 hidden and 38 guests (based on users active over the past 5 minutes)
Most users ever online was 5108 on Wed Nov 05, 2025 8:51 pm

Users browsing this forum: Amazon [Bot], Google [Bot], Majestic-12 [Bot] and 38 guests

Latest Blog Posts from Separation Science

Separation Science offers free learning from the experts covering methods, applications, webinars, eSeminars, videos, tutorials for users of liquid chromatography, gas chromatography, mass spectrometry, sample preparation and related analytical techniques.

Subscribe to our eNewsletter with daily, weekly or monthly updates: Food & Beverage, Environmental, (Bio)Pharmaceutical, Bioclinical, Liquid Chromatography, Gas Chromatography and Mass Spectrometry.

Liquid Chromatography

Gas Chromatography

Mass Spectrometry