Outdoor Disconnect Switch

[sonic02]

Hi there,

A quick question on disconnect switch. Can we utilize a 25kv outdoor disconnect switch on an existing 13.8kV line ? I know that 13.8kV disconnect switch exists but the client had purchased a 25kv disconnect switch instead.

Want some thoughts on that..

Sonic

 

[DTR2011]

perhaps. You should check the current rating and any fault closing ratings.

 

[jraef]

There is a Medium Voltage class of gear referred to as 15kV Class that is intended to cover 12.47 and 13.8kV systems. There are plenty of mfrs of 15kV gear, but it is not something typically sold through distribution. If you state what part of the world you live in we can likely guide you to some appropriate resources.

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[sonic02]

Hi,

I'm in Canada. The ratings (i.e continuous rating (900A) & mom.asymmetrical (40kA))for the 13.8 and 25kv outdoor disconnect switch is the same. I'm under the impression that a 25kV outdoor disconnect switch can be used on an exiting 13.8kV line but would just like to get some clarifications.

Note that this is an outdoor application on a riser pole.

Thank you..Sonic

 

[davidbeach]

Overkill, but it shouldn't be a problem if the rest of the ratings work.

 

[desrod]

The utility (in Canada) I used to work for, did a number of voltage conversions from 12kV to 25 kV. We used to rebuild/replace the existing network using 25 kV design and double voltage transformers.

Conversion was usually done over a number of years (3-5 year). New network sections would have been built as at 25 kV naturally.

With proper ratings, there is usually no problem as mentioned by David.

Desrod

 

[cuky2000]

Disconnect switches rated for 25 kV should be larger than the 13.8 kV.
Check if there is not issues with electrical clearances or other constains.