Advertisement

Support for Waters 501 Pump & Applied Biosys. 757 detect

Discussions about HPLC, CE, TLC, SFC, and other "liquid phase" separation techniques.

4 posts Page 1 of 1
I have an old pump and detector I'd like to use for some non-critical work. The manuals are long gone.

Both units power up. The pump runs and pumps liquid. The detector lamp powers up and ignites.

I'd be a lot farther along testing if I had manuals to refer to. A source of spare parts would also be nice.

Waters and Applied Biosystems do not have these manuals on their websites, as far as I can tell.

Any assistance in getting reference materials or in getting these operating would be greatly appreciated.

We have manuals for those instruments but paper version.

However there is nothing hard with those pump except prime heads if it is with old style check valves.
About detector it is one of the best and simple to use detectors i ever know... If you have any questions about controls just ask.

Thank you for offering assistance.

The pump seems to work, but the pressure pulses a bit, probably because I've yet to test it with a column or restrictor downstream. However, there's apparently some internal component disconnected. I have not previously worked with this pump, so I don't know what that is. Perhaps you can help by identifying for me the various components of these systems.

Let me describe the pump, which can be seen in this photo:
http://www.gcmsservice.com/Artwork/784.jpg

At the bottom is the inlet and purge valve. That is connected to the pump head on the left.

The output of that pump head goes to some component mounted inside the case. Can you tell me what that component is? (It is bypassed on my pump.)

Next the fluid travels to what is apparently a second pump head on the right, lacking check valves. I presume that this is a pump head that reduces pulsation from the first pump head. I do not want to disassemble these pump heads yet because I do not yet have a source of replacement parts.

From there the fluid travels to a component mounted near the top of the case. I'm guessing that this is a pressure sensor, since pressure does register on my pump. Can you confirm that?

I have confirmed that the detector lamp is operable, though probably weak. Fluid goes through the cell, and the cell doesn't leak.
I have confirmed that the cell windows are not obscured. With the detector set to the visible range, the lamp on and the cover open, I cannot perceive any color through the cell or reference beams, but this might just be because this detector lacks an incandescent lamp and the UV lamp produces too little visible light for the eye to perceive.

However, I have not been able to get a signal from the detector. Can you confirm for me that this signal would be read between the "REC" and "COM" terminals on the back of the detector? (The only other connector I find is a 25-pin connector like used for old RS-232 connectors.) I may have to open the case and check the electronics, but I'd rather avoid that if possible.

Thanks again for any assistance you can provide.

How you find that pressure pulses a bit? If it is about 5 bar (80 psi) it is ok for that model. About second head it is right about no valves on it. On top it is pressure transducer, so it looks smart and complete. Default lamp for 757 detector is a UV range 190-360 nm. It is still possible to order new UV or VIS lamp from PE and replace UV with VIS... But they won't work together at once. UV lamp sometimes work much longer ~4000 hours or more.
About REC and COM it is recorder and integrator outputs - 10mV and 1V. You just need a simple jack like microphone to obtain signal from it.
Good luck :)
4 posts Page 1 of 1

Who is online

In total there are 62 users online :: 2 registered, 0 hidden and 60 guests (based on users active over the past 5 minutes)
Most users ever online was 4374 on Fri Oct 03, 2025 12:41 am

Users browsing this forum: Amazon [Bot], Semrush [Bot] and 60 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