69 kV KSO OCB Tripping and closing coil current

[tem1234]

Hi,

The Tripping and closing coil are feeded by the battery at 125 Vdc. Do you know how many amperes and how much times is needed to open and close the breaker?

I check the manual but didn't see the answer.

Thanks

 

[crshears]

Model? Serial number?

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

 

[tem1234]

The model is a GE KSO 69 kV 1965
serial number 58135.

The mecanism is SD-19.

My question is for this specific breaker, but also for others of the same type because this question is often raised in battery calculation

 

[stevenal]

Per IEEE 485, momentary loads (less than a minute) are assigned a period of 1 minute for battery sizing, so the actual time period is not needed.

Watch out for aging type U bushings on those old oil circuit breakers. They make for an explosive combination.

 

[marks1080]

In my experience the older those KSO oil breakers get the more current they pull for a trip/close.

I wouldn't be surprised to see 20A through the trip cct. They're on the slow end for breakers. 3 cycles at least I would expect.

 

[crshears]

I started a response a while ago, then changed my mind, as I have no documentation to hand [and I don't trust my memory] to confirm whether this particular style of KSO breaker is compressed air close, spring open or big honkin' solenoid close, spring open; but I can't say I've ever heard of the trip coil current going that high with age...interesting.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]