HT Breaker

Better not to use your valued time in arguments.

the maintenance activity depends upon Indoor or outdoor.

Environment - is friendly or highly polluted.

Common to both of above is the interrupters and mechanism.

If the gas pressure is intact inside interrupters, The maintenance activities are same as of Bulk Oil CB. These are:

1. Periodic inspection of Arching contacts (Specially after a heavy fault cleared by the CB).

2. Measure contact resistance and ensure it is within limits (cross check with original factory test report).

3. Check closing and opening time.

4. Check simultaneously opening of all 3 phases (cross check with factory test report).

5. Check functions such as anti-pumping and Trip free functions etc.

6. Replace seals if suggested in O&M manual of manufacturer under PM schedule.

7. Lubrication of operating linkage.

8. Tightening of all moving parts to torques specified in O&M manual and tightening of all control wires.

In case of outdoor:

1. Cleaning of insulators.

2. Check temperature of joints of conductor to insulator, GOD (isolator contacts) using remote IR temperature detector.

3. Lubricate linkage and castle key mechanism of GOD.

For indoor:

1. Cleaning of insulators and visual inspection of any tracking.

2. Maintenance of fixed and moving contacts.

Common:

1. Secondary injection Test of Protection relays.

2. Primary Injection of CT.

3. Ratio test PT .

4. Measure station earth.

If other readers can add more of checks to the benefit of member concerned, he will be obliged, than pulling his leg.

Other advice:

Pl never think of sacrificing man power: Your priorities shall be:

First Safety of Personnel.

Next Safety of equipment

Last continuity of Power