Chromatography Forum

I'm running a Waters 2767 through a 2996 PDA, Masslynx 4.1 software. A couple of weeks ago we had a brownout that affected some of our instruments. The LC seemed fine, but this week the PDA started failing. When I turn it on the Status LED blinks as if it's going through its self check. There's a repeated clicking and then both the Status and Lamp LEDs blink. I thought it might be the bulb, but I replaced that to no avail. Out of the blue, it started working today for a few hours, but now it's failed again. When I click the status light in Masslynx, it says "PDA: Software failure."

If anybody could point me in some direction to solve this it would be much appreciated. I'm not an analytical chemist, so if I can't figure this out in a reasonable time my options are to call Waters and have them send a tech or get a new PDA. A tech will probably be silly expensive, I doubt I'll go that route. There are some 996's floating around the internet for a decent price (less than bringing a Waters tech in), are they interchangeable with the 2996?

The 996 is more or less interchangeable w/ the 2996 but it is not as good a detector for several reasons.

It could be a sticking shutter that is causing you intermittent grief. Call Waters and ask if your blinking lights and other symptoms as you've described them are consistent with that. Someone else on this forum would likely be able to tell you how to repair or replace that part, thus allowing you to avoid a "minimum" service call (which is expensive absent a contract because of the hourly rate that they apply for a minimum travel time, minimum time per visit etc.). You might also be able to save a buck by shipping the thing to them and having them do the repair in house if you're a klutz with tools, or they do not agree that it's just a sticky shutter.

Thanks DR, very helpful! Waters tech support seemed to agree it might be a sticky shutter (and tried to upsell me on having a tech come by, of course). I found a shutter for a decent price on LabX. Do you know if it's difficult to install? I'm not klutzy, but I'm not an ace with soldering or anything like that.

I've never done one, but I don;t think it would involve soldering... May be as simple as getting in there and doing a little dusting and lubricating.

Hopefully, someone here (with experience) can chime in. Also - (if you haven't done so yet) Google it - someone may have posted something somewhere about it.
Best of luck-