Is it improper to tap a feeder from the line side terminals of a fusible disconnect switch? A design I have observed is calling for a 60 amp feeder to terminate on the line side of a 30 amp fusible disconnect swith. The disconnect is fused at 30 amps and feeds an indoor air handling unit. The design call for additional line side lugs on the disconnect and 30 amp tap conductors feeding a roof top condensing unit. I'm not sure of the tap conductor distance as it relates to the tap rules. At the very least I would expect that the disconnect would have to be rated for 60amps. Any insight?
tapped conductor within a disconnect switch
- Thread starter whe4
- Start date
- Status
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- Semi-retired engineer
Re: tapped conductor within a disconnect switch
If the tap is on the line side, the switch itself will never see the tap current.
If the tap is on the line side, the switch itself will never see the tap current.
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
If the 60 amp supply is terminated at the lugs of the disconnect and the disconnect is rated 30 amps, this is not permitted. The addition of lugs to the disconnect so it can be used to tap conductors to another load does not make this a permissible installation.
If the tap occurs ahead of the disconnect and all other requirements are followed (such as 240.21(B)), this may be fine.
If the tap occurs ahead of the disconnect and all other requirements are followed (such as 240.21(B)), this may be fine.
- Location
- Massachusetts
Pierre C Belarge said:
I agree if we are talking about a 30 amp non fused disconect, however if it is a 30 amp fusible disconect I can use a 60 amp supply.
- Status