Another Monday Picture

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brian john

Senior Member
Location
Leesburg, VA
Somebody was not reading their NEC.

300.3 (B) 1



CTInductance.jpg
 
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brian john

Senior Member
Location
Leesburg, VA
Parallel conductors not routed together through a ferrous metal barrier. All they had to do was slot the barrier. Though I would have cut a 8" X 36 in hole and utilized insulaliner.
 

iwire

Moderator
Staff member
Location
Massachusetts
Which side of the metering is the hot metal?

If it is on th supply side they are steeling electricity to heat the building. :wink:
 

Twoskinsoneman

Senior Member
Location
West Virginia, USA NEC: 2020
Occupation
Facility Senior Electrician
Great pic! I really enjoy your IR pics.

I don't have my code book. But I am guessing it has some thing to do with smooth surfaces and plastic bushings.

(1) Paralleled Installations.​
Conductors shall be permitted
to be run in parallel in accordance with the provisions
of 310.4. The requirement to run all circuit conductors
within the same raceway, auxiliary gutter, cable tray,
trench, cable, or cord shall apply separately to each portion
of the paralleled installation, and the equipment grounding
conductors shall comply with the provisions of 250.122.
Parallel runs in cable tray shall comply with the provisions
of 392.8(D).

Exception: Conductors installed in nonmetallic raceways
run underground shall be permitted to be arranged as isolated
phase installations. The raceways shall be installed in
close proximity, and the conductors shall comply with the​
provisions of 300.20(B).
 

ibew441dc

Senior Member
Parallel conductors not routed together through a ferrous metal barrier. All they had to do was slot the barrier. Though I would have cut a 8" X 36 in hole and utilized insulaliner.

I would have done the same (8'' x 36"):smile:


Ultimately it should have complied with.....
300.20(B) Individual Conductors. Where a single conductor
carrying alternating current passes through metal with magnetic
properties, the inductive effect shall be minimized by
(1) cutting slots in the metal between the individual holes
through which the individual conductors pass or (2) passing
all the conductors in the circuit through an insulating wall
sufficiently large for all of the conductors of the circuit.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
I pulled the Discrepancy Report and the tech did not record the amperage. An over sight on his part.
The reason I asked is because it is my understanding that the equivalent to 300.20 in the Canadian Electrical code only applies to circuits that exceed 200 amps. Based on the number of conductors this was designed for a lot more than 200 amps, but the hot spot is only an 112 or so. I would expect that the current was a lot less than design load.
 
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