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6.9KV Vacuum circuit breaker rack in/rack out procedure
6.9KV Vacuum circuit breaker rack in/ rack out procedure

Dear Gents,

I have prepared the 6.9KV vacuum circuit breaker rack in/rack out procedure, I request you to kindly give your inputs to safe guard the personal to prevent hazards associated with rack in /rack out circuit breakers

Earlier we are rack in/rack out the breaker with the compartment door open, now we have modified the door & now we are able to rack in/rack out with compartment door closed

6.9KV Rack in Procedure

1. Identify the correct Breaker

2. Check Breaker visually for cluster condition, left out tools or any other external materials

3. Check the breaker is open & spring is fully discharged

4. Check the breaker is on local mode

5. Ensure that breaker control supply is switched off

6. Place the breaker in the compartment in test position & insert the breaker control supply plug

7. Close the breaker compartment door

8. Rack in the breaker

9. Open the breaker compartment door & check that breaker is in "connect" position & spring is in discharged condition

10. Close the breaker compartment door

11. Switch on the breaker control supply (MCCB#02)

12. Select the breaker in Remote mode

Breaker Rack out procedure

1. Identify the correct breaker

2. Confirm the breaker is open

3. Select the breaker in Local mode

4. Rack-out the breaker with the compartment door closed

5. Switch off the control supply (MCCB#02)

6. Open the breaker compartment door, ensure that the breaker is in test position, also check the breaker indication "Dis-connect" at local

7. Remove the control supply plug

8. Discharge the spring

9. Close the breaker compartment door

By William \(Bill\) L Mostia Jr PE on 19 February, 2011 - 3:10 pm

I am not a heavy electrical guy but it would appear that consideration of personal protection equipment (PPE) has been left out. See link below to see how PPE is important.

Have you considered NFPA 70E requirements in this regard or equivalent?

Dealing with heavy duty electrical stuff isn't for amateurs. Have your procedure reviewed by a qualified and competent electrical engineer in high voltage electrical systems.

William (Bill) L. Mostia, Jr. PE
Sr. Consultant
SIS-TECH Solutions, LP

Any information is provided on Caveat Emptor basis.