Maintenance and troubleshooting

While the air-assisted gravity conveyor has a relatively straightforward construction, and a limited number of moving parts to cause problems, there are issues with its maintenance 

---

Stand-alone computer systems, usually based on a personal computer (PC) or programmable logic controller (PLC), provide a separate computer system for each pilot plant. This allows for economical expansion for new units, separates pilot plants completely for maintenance and troubleshooting, and often has the lowest initial cost. Standardization can be a problem and software control, data gathering, and storage packages can be limited in size, scope, and capabiUty these are usually acceptable trade-offs. 

D. Rood, A Practical Guide to the Care, Maintenance, and Troubleshooting of Ctqjillary Gas Chromatographic Systems, 3rd Edn, Wiley-VCH, New York 1999. ISBN 3527297502. 

This section contains a list of steps the analyst can take to ensure successful HPLC operation and includes highlights of key maintenance and troubleshooting strategies. 

The control system is based on an industrial programmable logic controller (PTC). It includes all software required for the completely automatic operation, maintenance, and troubleshooting of the accelerator. ... 

Most manuals supplied by chromatograph manufacturers provide instructions for proper maintenance and troubleshooting. When checking the detector, it is advisable to use a sample that will not be adsorbed by the column, such as a hydrocarbon. For electron capture detectors a suitable test substance would be a halo-carbon, rather than a sensitive chlorinated pesticide. 

An additional feature of chemometrics that is appealing to process analytical applications, is the use of qualitative models to detect (and possibly even characterize ) faults in the analyzer s calibration, the analyzer system itself, and even sample chemistry and process dynamics. Such faults can be used to trigger preventive maintenance and troubleshoot specific analyzer or process problems — thus supporting the long-term reliability of the analyzer. Specific examples of such fault detection are given by Miller.3,4... 

Fundamentals of Maintenance and Troubleshooting. Dionex Corporation Training Manual, Dionex Corporation, Sunnyvale, California, 1992. 

Maintenance and troubleshooting. Due to their layered structure, grids are easy to install, remove, inspect, and maintain. Grid cleaning (especially if coked up) may be difficult, often impractical, but even in such cases, it is easier than that of random or structured packings. 

Good records of maintenance and troubleshooting actions should be kept. 

Referring to the maintenance and troubleshooting sections of an instrument s manual is highly recommended. Many individuals consult manuals only after a catastrophic failure and then only when all other problem-solving approaches have been exhausted. Modern HPLC systems often have self-diagnostic capabilities that help isolate the problem area within the instrument. 

Figure 6-15 Cross-sectional view of a dual-piston reciprocating pump. (From Walker JQ, Jackson MT Jr, Maynard JB Chromatographic systems Maintenance and troubleshooting, 2nd edition, New York Academic Press. 1977.)...

Rood D. A practical guide to the care, maintenance, and troubleshooting of capillary gas chromatographic systems, 3rd ed. Weinheim, Germany Vch Verlagsgesellschaft Mbh, 1999 344pp. 

---