20% Fill in a Trough Right?

[Joethemechanic]

I took the 3/4 plywood cover someone put on years ago off to use for a pattern to make a new steel cover and discovered another project. What if I fabricate a steel cover with additional space? Or just bite the bullet and replace it with a larger trough?

 

[infinity]

I don't see an issue other than the wood and of course it's very ugly. It's 20% fill for the conductors alone but 75% when there are splices.

376.56(A) Splices and Taps.
Splices and taps shall be permitted within a wireway, provided they are accessible. The conductors, including splices and taps, shall not fill the wireway to more than 75 percent of its area at that point.

 

[LarryFine]

And I'm willing to bet that the fill is nowhere as much as it appears.

 

[kwired]

FWIW, looks like split bolts with several conductors landing in them. Most if not all split bolts were only listed for two conductors.

Looks like it has survived the test of time so far and I can also say I seen very similar installs that lasted for 50 plus years as well.

 

[infinity]

And I'm willing to bet that the fill is nowhere as much as it appears.

I agree. With conductors of that size I would call it impossible to exceed the 75% fill even if you tried.

 

[Joethemechanic]

Looks like it has survived the test of time so far and I can also say I seen very similar installs that lasted for 50 plus years as well.

The original install was 1953 lol. Not sure when additional circuits were added. Roughly 5000 sq feet original building and an additional 5000 added in around 1970

 

[Joethemechanic]

Looks much better with the new cover I made for it. Have to paint it tomorrow

 

[Fred B]

View attachment 2579556View attachment 2579557

I took the 3/4 plywood cover someone put on years ago off to use for a pattern to make a new steel cover and discovered another project. What if I fabricate a steel cover with additional space? Or just bite the bullet and replace it with a larger trough?

Do you count the corrugated cardboard toward the 20% fill? (picture 2)

 

[Joethemechanic]

Do you count the corrugated cardboard toward the 20% fill? (picture 2)

And the wooden blocks. They were about 5 cubic inches each

 

[Eddie702]

I was going to suggest maybe buying a new trough the same size and cutting the back out of it and putting it on like a box extension but your done with it. looks like they put plenty of tape over the split bolts LOL

 

[Joethemechanic]

I was going to suggest maybe buying a new trough the same size and cutting the back out of it and putting it on like a box extension but your done with it. looks like they put plenty of tape over the split bolts LOL

I was going to bend up a cover in the brake kinda like a pan to give it some extra volume, but then I found a scrap of 12 gage sheet that was just about the right size and I got lazy. Not to mention that fused disco on the bottom has got to go, so that should free up some space. It's an unused branch circuit that fed an overhead crane that they removed sometime before I bought the place. They did bucket repairs for the dragline buckets in the back of the shop. When they built a new building at the breaker the crane went there

 

[kwired]

Do you count the corrugated cardboard toward the 20% fill? (picture 2)

And the wooden blocks. They were about 5 cubic inches each

I don't see why not. You may not count them as conductors or connecting devices but they still reduce free cross sectional area at their location.