140% Recloser Coil

[Mbrooke]

When would you use a 140% trip coil? What about a 200% for the matter?

https://www.eaton.com/content/dam/e...ly-controlled-recloser-catalog-ca280005en.pdf

https://www.eaton.com/content/dam/e...phase-trip-time-current-curves-tc280006en.pdf

 

[Mbrooke]

Somewhat- some major utility wanted 140X coils. Still don't fully understand why though.

 

[RRaghunath]

I am not much familiar with Eaton reclosers but think 140% will be able to provide protection against overloads as well, to some extent.

 

[waross]

How far past the rated KVA does the utility push their transformers for short time loading?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Mbrooke]

Pole pigs can be pushed to 200-300% when feeding cyclic resi load- 105-125% commercial with varying loads- station transformers are typically 50-60% loaded at peak but off the top of my head 115% overload for the loss one unit on the basis a reasonable loss of life is acceptable on behalf that a mobile unit will be brought in or the peak load will occur only on the few hottest days of the summer.

Here is one POCOs over loading limits- see page 7 and 8:

https://files.engineering.com/getfi...t-transformers_overloading_limits.pdf_001.pdf

 

[waross]

Pole pigs can be pushed to 200-300% when feeding cyclic resi load-

Past experience is probably a driving factor when selecting trip coils.
When A/C is the major load on a very hot day there is not much diversity.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[bwen08]

I don't know the context in the application, but 200% coils are the standard for Kyle reclosers. As the 140% pickup coils start at 280A, my assumption would be to provide increased sensitivity downline of the recloser. I could also envision the application of them if I were stuck utilizing a hydraulic recloser for 3 phase with a trip coil size exceeding 280A.

 

[Mbrooke]

Yup 200% is standard, but somehow X (140%) seems like an alternative option.