Chromatography Forum

I am experienceing waves in my baseline on several instruments (not all) that began when the air conditioning started. I am on a waters system with a 2487 dual wavelength detector. The period of the wave is about 10 minutes and it does not correlate with the room temperature. This happened last summer and then went away also.

There have been many threads about this in the past. You should check the archives for more detailed discussions.

We had the same thing happen here at my facility. Turns out the problem was linked to the air conditioning cycling on and off every 10 minutes.

Hi David

We also have the problem with the wavey baseline since we have installed an air conditioner. First, we thought it's a temperature effect. But immediate after turning on the conditioner (when the temperature hasn't changed yet significantly), the baseline drifted very strong.

You say you had the same problem. May I ask you how you solved it ?

Regards
Florian

First, don't rely on the thermometer on the wall to judge the temperature. Get an electronic thermometer and measure it at your detector; the forced-air ventilation might be blowing directly on the device.

If temperature really is not the problem, check the line voltage. You will need a voltage monitor for that.

Florian,

I was not clear in my original post; Mark Tracy's post reminded me of my error. Yes, the problem was linked to the air conditioning, but it was not temperature related. Instead, the HPLC, the data collection system, and the air conditioner were all connected on the same power grid, so when the the air conditioning kicked on, the power draw caused the baseline to spike up (or down, I don't remember which). Thus, when it turned off the baseline returned to normal. So, to fix the problem, we put the air conditioning on a different circuit or grid.

Sorry if I got the electrical terminology wrong - I am neither an engineer nor an electrician. Regardless, I hope this helps you out!

-Dave

Hi David

Thanlks a lot for your explanation. This helps a lot !! We just called the electrician...

Regards
Florian