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Load break switches

Load break switches

Load break switches

(OP)
How many times can switches like these break full load current, or at least interrupt normal feeder current (200amps)?

http://www.sandc.com/en/products--services/product...


I can't find any duty cycle listed. Asking around I am getting answers from never, to parallel loop splitting only, to as needed without any concern.

RE: Load break switches

You use the term "switches like these" but it's not clear if you mean "this specific brand and model", or "this kind of generic switch".

1. Call the manufacturer of the specific make and model you propose using, with your duty cycle and limits (voltage, current, number of cycles, length of time between cycles).

2. Call two other makes of similar switches, ask the same question. Get the answer in writing, not by voice mail or telephone.

RE: Load break switches

Please see snapshot attached which belongs to EATON make LBS.
So it is better to get detailed info from mfg.

As per this specific brand is concerned, I think it can close for 42kAp = 2 operations, 21kAp = 10 operations.

Thanks,
Vijay

RE: Load break switches

(OP)
@racookpe1978: More specifically Omnirupter/alduti rupter switches as I hear those have the best reputation. A lot of similar switches by competitors are known to be nothing more than decorations in that they seize up.


Here is an interesting powerpoint on the matter, but sadly the manufactures are not listed in the final test results, however the results pretty much sum up what many in the field have discovered.

https://www.neetrac.gatech.edu/publications/OHLB_I...

RE: Load break switches

(OP)
@vijaypandiyan: Those look like they are for underground gear?

RE: Load break switches

At the bottom of the S&C link you provided, there is a Product Literature tab.

According to the descriptive bulletin for the Omni-Rupter, the expected life is ~500 full load operations,~2000 mechanical operations.

RE: Load break switches

(OP)
Thanks :) Found it:

http://www.sandc.com/globalassets/sac-electric/doc...

Quote (S&C)

In typical feeder-switching applications with
a mix of duties including switching magnetizing
current, line-charging current, moderate-load
current, plus occasional switching of full-load
current at maximum voltage, these interrupters have
a life expectancy of 500 operations. Omni-Rupter
switches are designed and tested for a mechanical
capability of 2000 operations

Sounds like full load current should be avoided unless an emergency? I have a feeling its 3-5 operations for 900amps at 25kv.

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