scope:

In refineries, all areas are classified for electrical equipment installation (refer to the latest edition of NFPA 70 or applicable local codes, or both, and API RP 500A). Suitable precautions for particular area classifications must be observed for inspection of electrical equipment. In general, inspection should not be exercised on energized circuits; however, the following circuits are exceptions:

1. Infrared surveys.

2. Insulating oil analysis.

3. Vibration analysis.

4. Checking battery voltages and specific gravity.

5. Lubricating oil analysis.

6. Checking general equipment conditions (such as transformer temperature and pressure, electrical loading, metering, ground lights, and so forth). While checking general equipment conditions, the senses of sight, smell, and hearing can be used to confirm the aforementioned mechanical methods.

The voltage levels encountered in refinery systems can vary from millivolts to as high as 138,000 volts.

This chapter provides a basic guide or checklist for electrical equipment inspections and discusses the reasons for inspection, causes of deterioration, frequency and methods of inspection, methods of repair, and records and reports. Safety and efficiency of operation are emphasized. The items that are discussed in Chapter XIV can only be determined locally by the persons responsible for performing the inspection. Local personnel capabilities, equipment age and model, influence of local atmospheric conditions on the rate of deterioration, and the like should be considered.