Pre-Commissioning Checklist for MCSeT Switchgear

Verification of installation

Alignment, Accessories used as guided in documents, Cubicle placement as per approved GA drawings, Castel-key interlock verification as applicable, Check the rating of the components and equipment, Check external earthing & continuity for all cubicles, Ensuring the identification of cubicles are same on front and rear side, and Check documentation of applied torque on bus bars & other applicable joints.

Control bus and intern cubicle connectivity

Ensure inter-cubicle connections are taken care.

Mechanical operational test

Know your switchgear before performing any operational/interlock test.

Study the applicable scheme and its requirements for this project.

Conduct several racking/rack out and open/close operations for VCB, switches, and earth switches as applicable.

Record operational counter details if applicable before and after the completion of the operational test.

Contact Resistance Test for main bus bars

Apply final torque to identification before starting activities.

Functional Test/Scheme check of the cubicle as per approved schematic diagram

Familiarize yourself with the applicable scheme and its requirements.

Current Transformers and Voltage Transformers testing as applicable

Test applicable components and normalize all links.

Secondary injection testing of protection relays as applicable

Ensure proper functionality of the tripping scheme.

Perform secondary injection with approved protection setting.

Any deviation must be documented, and the end-user must be notified officially if the final relay setting is not available.

Insulation Resistance Test on the power circuit

Remove VT from the circuit.

Remove surge arresters from the circuit.

HIPOT/Power frequency withstand voltage test on a power circuit

Remove VT from the circuit.

Remove surge arresters from the circuit.

Short-circuit CT secondary and ground CT links.

Conduct a HIPOT/Power frequency withstand voltage test at 80% of factory Voltage for one minute.

Check of IP / sealing methods

Prior to closing the front and rear cable doors (covers), it is essential to inspect the IP for cable entry, including checks at front doors such as cable door arrangements, MV doors, and LV compartment doors. It's also important to verify the IP from the cable door or back side covers. Checking IP is crucial for structural enclosure. Additionally, the IP for the top cover needs to be guaranteed, and any unused openings on the sides, top, and bottom of the cubicle should be sealed off to help ensure IP and safe cubicle functioning.

Primary injection test on current transformer and voltage transformer

It is crucial to conduct this test to identify any errors in the CT and VT circuits.

Standardize all the shorting links that were adjusted during the Insulation test and HIPOT/Power frequency withstand voltage test.

Verify that all relays and relevant measuring devices display the appropriate readings.

Once the testing is completed, make sure all the links are returned to their normal state. For instance, the VT circuit should not be short-circuited, while the unused core of the CT must be short-circuited.

Remove temporarily created conditions

Always remember/mark temporarily created conditions to carry out the operation. (Keys/Solenoid/upstream interlocks/process control feedback etc.)