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Hi vacuum of Triple Quad 6400 fluctuates

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

8 posts Page 1 of 1
Hi all,

Our Trible Quad 6400 Agilent is working well. But it has a problem recently. The high vacuum reading is normally 5e-5 , and sometimes it jumps to 5e-1 suddenly then jumps back to normal value. But now, it jumps more to the low reading and stay there for long and it prevent us from analyzing samples. As I know the vacuum is normal. There's no leak.
Any of your advice is very precious for us.

Regards

Hi haiedc,

I vaguely recall getting this issue after a motherboard replacement. The firmware was a bit askew.

Assuming that you haven't just had your motherboard replaced, I'd go through pump down/vent and power cycle your ms to see if you can return to high vac. {edit:} upon rereading your post, I see that it isn't likely to be software related, but you may as well power cycle your instrument because it will be the first thing your engineer asks you to do.

I think this might be a problem with the ion gauge. Take a close look at it to be sure that it looks OK. Might need replacement or possibly just a loose or worn cable. Of course, be sure to power down your instrument before messing with the gauge.

Thank you both. I now have to deal with it by shuting down and power back on. It's OK say, for a week or so.

Get this fixed! If you shut down your instrument every week, you'll be buying a new turbo pump fairly soon, not to mention other parts that don't like being powered on and off.

Does it have a reset button? (our Agilent single quad does). If so, if this is a software issue, you would do much better to use the reset button.

Hi haiedc,

1. Which version of the 6400 do you have? i.e. how many pumps do you have?

2. This is worth a service call. If, for example, your collision cell valve is getting stuck open (just as an example), you'd prefer to have that fixed vs. paying for a new pump.

To Matthew : I do not think it's a pump problem because even when the reading jumps down to 9.9e-1, the instrument still operates normally. Only if the Hivac reading stays at that value too long (about 5-10min), the system shifts to Not Ready Status. It's a 6410 .

To Lmb : I will find the reset button. So i can reset the MS during standby?

I would also strongly suggest to find out what the problem is or get it fixed by a service engineer. It could be a safety hazard (worn cables) or could end up costing you a lot more money in the long run (turbo or worse).
8 posts Page 1 of 1

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