This weekend, with help from my wife and kids, I pulled a wire bundle consisting of six 4 AWG conductors and one 8 AWG EGC through about 110 feet of 1 1/4 EMT with about 800 degrees of total bend. To stay within the NEC requirement of no more than 360 degrees of bend between pull points, the total run was divided into three sections. There is a subpanel (not the critical loads subpanel) with a 60A breaker serving as an AC disconnect between the middle and one end section, and an 8" square box between the middle and the other end.
This insane conduit run was necessitated by the placement of my equipment shed outside, the run of conduit along a chain-link fence, the need to go over a doorway in my garage, and the best route I could figure out in the ceiling of my basement. The electrical panel is unfortunately on the other end of my house from where the equipment shed had to go, and the solar array is 150 feet further away from the electrical panel. (For that run, less copper was needed because I'm running at around 440 Voc.)
I needed two hots and a neutral from the main panel to my Outback Radian in the shed, and two hots and a neutral back out again to the critical loads subpanel that sits five feet away from the main panel. I'll be moving my selected branch circuits over to the subpanel soon--fairly simple since the wires go straight down the exposed basement wall to the main panel and I'll just have to move a few of them over. No splicing needed--the branch circuit conductors will be shorter after their move.
I oversized the wire because I don't want the lights flickering every time the well pump kicks on or someone uses the microwave. It doesn't take much resistance per foot to get voltage drop at 20 A with 220 feet from main panel back to the subpanel.
What a project! I fashioned an eye splice in a 3/8" twisted polypropylene rope and attached a "Chinese finger" pulling grip to it. I wrapped four of the 4 AWG wires together with black tape, slid the grip over them, and taped the two other 4 AWG wires and the EGC to the bundle a few inches further from the end, staggering the points of attachment so there was a nice taper. The whole thing barely fit into the conduit, but lots of lube, one person pushing the bundle in at one end, and me pulling with most of my 200+ lbs. on the other end got the job done. I was actually surprised at how well it went.
By the way, the NEC limit for 1 1/4" conduit fill is seven 4 AWG conductors. I was just a little under the limit, and that's without considering the EGC differently from a conductor. But with a 50 A breaker at the Outback Radian, these big wires are not going to get near their 90 degree C temperature limit.
This insane conduit run was necessitated by the placement of my equipment shed outside, the run of conduit along a chain-link fence, the need to go over a doorway in my garage, and the best route I could figure out in the ceiling of my basement. The electrical panel is unfortunately on the other end of my house from where the equipment shed had to go, and the solar array is 150 feet further away from the electrical panel. (For that run, less copper was needed because I'm running at around 440 Voc.)
I needed two hots and a neutral from the main panel to my Outback Radian in the shed, and two hots and a neutral back out again to the critical loads subpanel that sits five feet away from the main panel. I'll be moving my selected branch circuits over to the subpanel soon--fairly simple since the wires go straight down the exposed basement wall to the main panel and I'll just have to move a few of them over. No splicing needed--the branch circuit conductors will be shorter after their move.
I oversized the wire because I don't want the lights flickering every time the well pump kicks on or someone uses the microwave. It doesn't take much resistance per foot to get voltage drop at 20 A with 220 feet from main panel back to the subpanel.
What a project! I fashioned an eye splice in a 3/8" twisted polypropylene rope and attached a "Chinese finger" pulling grip to it. I wrapped four of the 4 AWG wires together with black tape, slid the grip over them, and taped the two other 4 AWG wires and the EGC to the bundle a few inches further from the end, staggering the points of attachment so there was a nice taper. The whole thing barely fit into the conduit, but lots of lube, one person pushing the bundle in at one end, and me pulling with most of my 200+ lbs. on the other end got the job done. I was actually surprised at how well it went.
By the way, the NEC limit for 1 1/4" conduit fill is seven 4 AWG conductors. I was just a little under the limit, and that's without considering the EGC differently from a conductor. But with a 50 A breaker at the Outback Radian, these big wires are not going to get near their 90 degree C temperature limit.
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