Chromatography Forum

Hello,

we have a old HPLC (agilent 1100), no one was using it for a longer period. Now I'm working with it since 3-4 weeks. Yesterday I performed a run with a few samples. after the 2nd sample the autosampler-arm took the sample to the needle, injected the sample and on the way back the arm simply stuck in the middle (lights turned red) => restart of the module did not help!

Seems like it is a mechanical problem, since I think the autosampler was not maintained for a long time.

Does someone know how to get the arm back on the starting position?

Thanks,
Mike

Hello

If it is mechanical problem like tension belt or stepper motor it is quite serious, you will probably have to replace transport assembly (or you can try to fix it if you know how)
However you can make simple test:
1.Switch sampler off
2.use your fingers to move transport arm somwhere in the middle (you need to turn metal rods behind)
3.Swith sampler on

If you had just accidental error sampler should initialize without problems.
Just watch sampler during initialization and see (and hear) if you spot something unusual. If you hear any strange sound when arm is moving you've got problem with transport arm.

Just keep in mind that if you have error you have to wait about 30 min before you switch sampler on again - motor(s) need to cool down a bit.

Regards

Tomasz Kubowicz

Works!
Thanks a lot for your help!