MSD newbie questions

[intereco]

Hello,

Couple years ago I bought on Ebay used HP5890 with FID and EPC. About one year I spent to refurbish device. For now it works ok and as we use it for environment analysis (ambient air and emission sources) often I feel lack of MSD. Could you please share information on my question:

1. is there possible connect MSD to my HP5890 with FID together?
2. is there big differences between MSD 5970 - 5971 - 5972?
3. as far I understand 5970 detector unable to connect to PC or it will be enought difficult?
4. which problems I can meet with used MSD - I mean issues that appears with time?

Thanks a lot!

with best regards,
-vadym

[R13]

1. It can be done, this kind of the instruments were delivered when ordered.

HOWEVER, the MSD needs the hole in the GC column compartment. Factory prepared GC/FID/MSD have it made already - Yours will not have it. Not sure if some internal parts have to be re-arranged to accept MS transfer line. You probably will miss some internal connecting cables.

There is also problem with instrument configuration in the software - even the last Agilent models can not operate MSD and FID simultaneously - you use just one and have to shut down the other and remove it from configuration in the software. One user I know was using this kind of instrument (5890/5971) with PC for MSD measurements and simple integrator for FID.

2. 5970/ 5971=Big differences, 5971/5972= evolutionary improvements.

3. Not sure what You mean. Any MSD has to be connected to PC. However software support probably is not available anymore for this model and new Chemstation versions might not support this model. Which means you have to use old software/PC hardware (including PC communication card) which might be difficult to obtain. Some (or maybe even all) original 5970 software was running under different operating system than Windows as far as I know.

4. Contamination and spare parts availability issues - you will have more different parts failing due to wear/aging. Electron multipliers have to be changed regularely and old types are not available anymore while new types might be difficult to install because of different construction. Rubber parts can start to leak. Electronics might need advanced adjustments to keep the performance.

[mkigls]

It is straightforward to connect an MSD to the 5890 - there is a knockout in the oven wall on the left side, which is where the transfer line comes in. You'll need the G1701 series software (AA for a 5970, AA or BA for the '71 or '72), a PC with an ISA slot and an interface card for the HP-IB. It runs just fine under Windows 98SE.

It is possible to run the MSD and the FID simultaneously; however, you need to pipe the FID signal through a 35900 A/D - HPIB converter box. You can take the signal out of the HP-IL card. The FID signal will appear as a separate channel, which will allow you to overlay both signals.

As far as sensitivity goes, the '70 and the '71 are very similar - in fact, our experience has been that the '70 is slightly more sensitive for semivolatile compounds. You'll get improved sensitivity from a '72 - maybe a factor of 5 or so. The '70, if cared for, is a very rugged box - metal quads, straightforward hardware, etc. Although it is older there is an abundance of parts and support - we still have several that we run. Depending upon your needs, I'd readily recommend a '70 for routine use.