PRE-COMMISSIONING TESTS AND CHECKS
1- Visual Check and Inspection of all Electrical Equipment
A visual check will be carried out on all electrical equipment, internally and externally, to determine that no transit/erection damage has occurred (or where this has happened that satisfactory rectification work has been done). All control and relay panels, local control panels, Switchgear and electrical devices will be internally checked for compliance with the approved drawings and approved connection wiring diagrams.
The tests carried out in order to satisfy the above will be: ‑
1. Internal Panel Wiring Compliance Visual Check
2. Internal Panel Wiring/Devices Insulation Check
3. D.C. Supply Checks
4. A.C. Supply Checks
5. Scheme Checks (Positive and Negative Rail Principle)
All relays will be visually checked to see that there is no packing, dirt, metal swarf, etc., present in the magnet gaps or on the contacts. All connections will be checked for tightness on the relays and at all other wiring terminations including the terminal blocks.
All devices shall be checked to see that they are clearly numbered/identified in accordance with the general arrangement drawings and that the phases are marked where appropriate.
These tests will be repeated during the acceptance testing stage by the erection staff in liaison with a commissioning team member, when they will be witnessed by the client. www.sayedsaad.com
3- Bus Wiring
All inter-panel bus wiring will be tested and checked in accordance with the appropriate termination diagrams.
Insulation checks will be made using a 500V Megger on each bus wire to earth and from each bus wire to all others. These checks should be carried out with all individual fuses, links, miniature Circuit Breakers, etc., open or removed at a) the source of supply and b) all incoming and outgoing circuit panels and Switchgear. www.sayedsaad.com
4- Multi-Core Cables
All multi-core cables will be tested and checked in accordance with the appropriate termination diagrams.
The insulation resistance will be measured using a 1000V megger after all the multi-core cables have been connected to the erected equipment. (These tests on the multi-core cables although done at the pre-commissioning stage to sort out any obvious problems will be repeated during the acceptance testing stage).
5 - Batteries and Chargers
The batteries and chargers will be checked to see that they have been erected / assembled correctly in accordance with the manufacturers recommended procedures.
The tests that are carried out at this stage will be to determine that the batteries and chargers are functioning correctly, within the recommended tolerances, so that their performance can be relied upon during the commissioning of the rest of the substation equipment.
The responsibility for carrying out the above will be taken by a SCE. The actual acceptance tests, including the time-consuming discharge tests, to be witnessed by the client, are carried out towards the end of the commissioning programme.
6- 132kV GIS Site Tests
These tests are carried out in accordance with the format of the Works Site Test Report. The tests conducted are:
1. Bus-Bar and Connections - Conductivity Tests
2. Circuit Breaker - Contact Resistance Checks
3. Circuit Breaker - Contact Timing Tests
4. Mechanical and Local Electrical Operational Checks
5. Air and Gas Leakage Tests
6. SF6 Gas Pressure Switch Setting Check
7. Compressed Air System Sequence Checks
7- 132/11.5kV 30 MVA Transformer Site Tests
The Transformers are inspected and tested in accordance with the factory check sheets for Transformer installation. As well as detailed inspection this also includes oil testing.
8- Shunt Reactor
These tests are carried out in accordance with the format of the Works Site Test Report. The tests conducted are:‑
(1) Visual Checks. www.sayedsaad.com
(2) Winding Insulation Level.
(3) Oil Tests. www.sayedsaad.com
Oil / Winding Temperature Gauge Calibration Fan Control