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Posted By: shortcircuit Building Disconnect - 01/05/05 02:01 AM
Today at the supply house I asked for a Nema 3R 240 volt 60 amp single phase non-fusible disconnect switch suitible for service equipment.Well they came out with a 3-pole safety switch.

I want to use this for a Building Disconnecting Means on the exterior of the accessory building before entering to the panel.My overcurrent protection is where the feeder originates.

Maybe it is more common to use a Nema 3R circuit breaker enclosure with a circuit breaker as the disconnect instead of a non-fusible switch.

What have you used or seen in the field. Any part #'s would be helpful.

shortcircuit
Posted By: resqcapt19 Re: Building Disconnect - 01/05/05 03:04 AM
I don't think that you will find many non-fusible disconnects that are listed as service equipment.
Don
Posted By: JBD Re: Building Disconnect - 01/05/05 02:31 PM
Most of Square D's non-fusible 240V and 480V disconnects/safety switches are UL Listed as service entrance.

Square D does not make a knive blade design 2 pole non-fusible switch except as NEMA 3R 240V 30 & 60A sizes. So, it is likely that your supply house only stocks 3 pole devices.
Posted By: velect Re: Building Disconnect - 01/05/05 07:06 PM
A breaker disconnect would be a lot less expensive. Almost half the price
Posted By: Wirenuttt Re: Building Disconnect - 01/06/05 01:07 AM
We sell the enclosed circuit breaker 3R for service disconnects. It is a lot less expensive. Smallest we sell is the 100 amp rated size. Just place a 60 amp 2-pole cb in it.
Posted By: Steve Miller Re: Building Disconnect - 01/06/05 01:59 PM
If there is a breaker at the source of the feeder and it's coming from another panel, it's a sub panel not service eqpt. Use any 3R disconnect.
Posted By: shortcircuit Re: Building Disconnect - 01/07/05 02:10 AM
I decided to get a Nema 3R circuit breaker enclosure suitable for service equipment for my accessory building disconnect which has a feeder run underground to it from a seperate building.

A knife style non-fusible disconnect suitable for service equipment was unavailable in the supply house.

I wanted to use a knife style disconnect outside the building because I envisioned that it would be easier for emergency personal to identify it as the building disconnect and it would be just a throw of a handle to shut down the building power.

Steve Miller...225.31 requires a disconnect and 225.36 says it must be suitable for service equipment.

thanx

shortcircuit
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