Commissioning of isolators and earthing switches

Commissioning of isolators and earthing switches

Guidelines of Commissioning of isolators Some of the important guidelines to be followed before energizing the isolators and earthing switches. For your reference, please find below the step by step process of commissioning of isolators: Isolators can be of the following types Centre break Double break Pantograph Operation of isolators can be motorized or manually operated. The nameplate details of an isolator consists of rated current, rated voltage, short circuit current rating, the auxiliary voltage required for operation etc. For a motorized isolator closing & opening is normally controlled by ‘close’,…

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Commissioning Procedure for Electric HT Motor

Commissioning Procedure for Electric HT Motor

Quick Guidelines of Industrial Electric HT Motor Pre-Commissioning checks:- Check for the proper fixing motor on the foundation. Check that the motor can be easily turned over by hand. Check motor winding resistance on each phase; verify that they are equal. IR value and PI value of the motor to be checked. IR values and HV test on the cable to be performed. Check all the tripping and alarm signals from winding and bearing TRDs (through scanner if provided) Testing of ht motor protection relay and tripping of the circuit breaker…

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Commissioning Procedure for HV / HT Cable

HT-CABLE

Step by step Commissioning guidelines of HV/ HT Cable Check continuity of the HT cable to confirm R, Y  and B phase at both ends as per marking. This is especially important when there is more than one run of cable phase; any cross-over will result in a dead  short circuit. The Cable screen is to be earthed at one end only. Cable gland plate should be of non- magnetic type e.g. aluminum. Perform HV / HT test on the cable.Apply only Dc voltage, as cables have relatively higher capacitance. Check…

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Electrical Testing and commissioning -Safety Guidelines

Risk and Safety assessment for Electrical Testing and Commissioning Safety of testing and construction personnel should be the primary  consideration at all times. The following are some guidelines to ensure safety :   Ensure that proper safety gear is used. These include safety shoes, safety helmet, safety gloves(Rubber-Electrical), Rubber mat, fire extinguishers etc Whenever work is dine on power circuits (LT or HT), all power sources must be isolated by opening and withdrawing the circuit breakers. Earthing switches should be closed or if not available local  earthing should be done.…

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Power transformer factory acceptance test checklist

Power transformer factory acceptance test checklist

Why Power transformer factory acceptance test checklist is required ? Every power transformer has gone through 2 type of testing before charging.The  First testing is done at the factory, under the supervision of vendor( who purchase it) and the second testing is done after installation at the site. Actually, the manufacturer offers the pre-inspection check before dispatching the material from its store and all of the testing cost carried by the manufacturer. So many of the manufacturer try to hide or bypass some test. Every person has no idea which…

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