HP 5890 II, 5890 II Plus Chromatographic Troubleshooting

Chromatographic Troubleshooting

Introduction

This chapter is concerned with diagnosis: the process of going from unexpected behavior of the HP 5890 SERIES II (hereafter referred to as HP 5890) (symptoms) to the probable location of the difficulty (causes).

Problems arise from many causes. Some of these are:

CElectronic or mechanical failure

CContamination in critical areas, such as detectors

CIncorrect or inappropriate setpoints

CLeaks, column or septum bleed, or other chromatographic difficulties

These may interact to a bewildering degree: For example, baseline problems may arise from any of the above areas. Accordingly, this chapter is organized by symptoms, with reference to most probable causes.

Baseline symptoms

Position

1.Baseline not at left (lower) part of chart:

C Check the zero of your recording device: An attenuation or range change during the run may be responsible.

C Check TCD signal polarity.

2.Baseline position changes suddenly during the run:

C This usually results from a range or attenuation change.

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