Chromatography Forum

Hi all,

I am a postgraduate student working at my year project with LC/MS/MS.
But instrument is not well supported from the organization.
And many technical problems are critical.
Now a problem happened with Nitrogen generator. Compressors are OK, but compressor test fault and pressure on the pressure sensor is 0. There is no input of nitrogen from the tube to the sensor. Solenoids are OK.
What can cause such a problem?
If somebody had similar problem please help.

Thanks

Hi,

Your description is somewhat confusing.
Is the air pressure high enough? N2 generators need some "limit pressure" to be reached before they start generating N2, when the pressure is too low- internal electronics shuts down the process.

First, You could mention the model of the generator, maybe somebody has the same type and there might some specific problems with the particular model.

Second question is - most N2 generators need regular maintenance (for example each 4000 hours) involving filters and sometimes internal valves exchange - was maintenance performed on Yours as required by the manual?

You should try to find authorised seller/service company in Your area for this generator. At first try to discuss the problem with the service by phone - it is free (if they cooperate). It is likely that service person visit might be needed as You do not have tools/knowledge to test function of the generator internal parts.

Hi

Thanks for your answer


It is difficult to uderstand if the air pressure high enough.
Generator is Peak Scientific.
Pressure sensor show 0 while testing air pressure (Compessor Test Fault, all 4 compressors)
But all inside the compressor is OK, required maintenance was performed.

I have already asked authorised seller/service company and even sent a solenoid for test. But unfortunally they cannot help. And service person visit is needed indeed. We tested some by phone and e-mail, but the reason is not uderstandable. The problem is that the organization does not support this visit and.....it seems that I have 2 ways - switching to nitrogen balloongs or finding the reason of failure by myself or with volunteer help. (((((((

Looks like one of the valves is closed ans air is not comming to the sensor, but I can not test it yet(((
Air comes to the block with inscription "copmressor test", but no air input is near in the tube connected to the pressure sensor....

P.S.: sensor is OK, It shows 0 cause there is no air it the tube, when I took another tube with air and connected it to the sensor it showed pressure.

And yes...I was wrong in previous post, not nitrogen but air pressure is not enough during the compressor test.

You need an engineer who understands compressed gas installations. It's quite possible you've got a stuck solenoid (it happens), but if you tinker with this yourself, you could potentially explode something or send bits of generator flying around at alarming speeds. If you injure yourself or others, your organisation's unwillingness to pay for a service visit will pale into insignificance compared to the lawsuit and safety-inspector trouble they'll be in. You could maybe use this argument to persuade them to repair it?

As a student, if you need a quick fix, it is quite possible to run an LC-MS on cylinders of oxygen-free nitrogen. It will just cost a good bit in cylinders, and you'll be carrying them around a lot as consumption is high. Maybe after you've got through the first 20, someone will see sense and invest in a decent generator.