ryan hedlund
New member
were in the code can i find that you cant use conduit instead of fuses in a disconnect
fuses
- Thread starter ryan hedlund
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- Location
- Lockport, IL
- Occupation
- Semi-Retired Electrical Engineer
That's a scary question! I presume this is an academic question, and that you are not really trying to prove to someone who wants to do this that it is not allowed.
My book is not handy. But I believe early in 240 it will say something about having to protect all conductors from overcurrent. That is the function of a fuse, and a conduit cannot perform that function. I think your answer can be found there.
My book is not handy. But I believe early in 240 it will say something about having to protect all conductors from overcurrent. That is the function of a fuse, and a conduit cannot perform that function. I think your answer can be found there.
mdshunk
Senior Member
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- Right here.
Probably 110.3(B) is the closest you're going to get. Some people use a 4-pole disconnect to switch the neutral and put in a "dummy fuse" in the neutral position. (3-pole disco for single phase). The "dummy fuse" is an actual manufactured part, made for that purpose, whereas a piece of conduit or copper pipe is not.
- Location
- Massachusetts
I will assume that the conductors in question are already properly protected somewhere.
Even then you can not use conduit as a conductor.
At the very least there is 110.3(B) which requires us to use listed and labeled equipment as instructed. I am very sure you will not find any instruction allowing conduit to be used in the switch.
Then there is 110.5 which requires conductors normally used to carry current be copper unless another material is allowed by the code elsewhere.
There are 'dummy fuses' that are made to turn a fused disconnect into a non-fused disconnect but the application of even those is pretty limited.
Even then you can not use conduit as a conductor.
At the very least there is 110.3(B) which requires us to use listed and labeled equipment as instructed. I am very sure you will not find any instruction allowing conduit to be used in the switch.
Then there is 110.5 which requires conductors normally used to carry current be copper unless another material is allowed by the code elsewhere.
There are 'dummy fuses' that are made to turn a fused disconnect into a non-fused disconnect but the application of even those is pretty limited.
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