Tests for installation and troubleshooting
The following are a few tests used during commissioning and troubleshooting:
1. Insulation test: This is the most important test for troubleshooting of any electrical equipment. Depending on the system, a suitable test voltage is applied to check the insulation resistance between the live conductors and earth.
2. Earth continuity test: For electrical equipment, continuity between the exposed portion (metallic) of earthed equipment and the earth terminal is
checked. Resistance value should be low. If resistance value is high, then it is indicative of poor earthing.
3. Flash test: To check the insulation strength of cables, a high voltage (as
specified by the cable manufacture) is applied in the same way as for the insulation test. This determines the withstand capability of the cable insulation.
4. Electronic earth test: Generally, for microprocessor-based or electronic- based sensitive devices, separate earthing is provided. This is called electronic
earth. The voltage between the electronic earth and the power earth should be lower than 2 V.