Non Fused Service Entrance Rated Manual Transfer Switch

[tallen98908]

I recently looked at an installation that has a manual non fused transfer switch that is being used a service entrance equipment. I looked through the code and I cannot find and installation that allows this. I was under the impression that to use the transfer switch as service entrance equipment it would have to have over current protection. This installation supplies a domestic water pumping station we are proposing to replace the existing ancient MCC on. I am certain if I am to replace the MCC the inspector will not allow me to reconnect to this existing non fused switch. Am I wrong or is there language in NEC that allows this?

 

[augie47]

Three items you might investigate.
1. 230.91 allows the overcurrent protection to be integral with OR immediately adjacent to the disconnect
2. If I am not mistaken some double throw safety switches are service rated and thus meet 230.70(C) (I believe they have a center off position)
2. Non-fuse safety switches are normally have a 10k AIC rating which may have a bearing.

 

[qcroanoke]

1. 230.91 allows the overcurrent protection to be integral with OR immediately adjacent to

Agreed. if your MCC has a main and is right beside it and/OR if the MCC has 6 or less overcurrent devices in it. And is right beside it. Not sure about the 6 throws of the hand rule being as it is an MCC.

 

[Cow]

My folks have one of these installed in their barn:

https://www.platt.com/platt-electri...e/Eaton/DT224URK-NPS/product.aspx?zpid=429546

I tried to look up the AIC rating on their catalog page listed but I didn't see it in the specs. Being nonfused I'm curious what it is rated at, if it's really only 10k.

 

[jim dungar]

They are 10kA.

http://www.eaton.com/Eaton/Products...ches/DoubleThrow/GeneralDuty/index.htm#tabs-2

Page 28 of the consulting engineers guide.
"...For applications that require a UL listed short-circuit rating
of greater than 10,000 rms symmetrical amperes, an
Eaton non-fusible switch must be properly protected by
the appropriate class and size fusing noted. Otherwise, this
non-fusible switch must be replaced with an Eaton fusible
switch that uses the appropriate fusing required...."