ThirstyEndgrain
New User
- Location
- Woodacre CA
Hi all, thank you in advance for your help. I've poured through some older posts on the question I'm asking and I just want to make sure I'm getting things right. I'm a general contractor rebuilding a house that was once half mine (long story), and I'm pretty comfortable doing most general residential wiring tasks, since this is "my" house and in the interest of savings I'm not planning to hire an electrician to do this panel replacement.
Posts I've read:
https://forums.mikeholt.com/forum/a...es-in-pipe-sleeve-into-breaker-panel?t=179892
https://www.electriciantalk.com/f9/nm-cable-through-back-surface-mount-panel-58938/
Among others...
I can post pictures later when I'm at the job but I'd like to get this out there because we're trying to get moving. I'm replacing an old exterior surface mounted 100A main panel with a new 200A main panel, old panel is fed from above and new panel will be fed from below once we run conduit from pole. Need to install new panel temporarily since we're running all of the siding right now, and don't want a big old extra hole where the old panel was.
Old panel has all branch circuits coming through a ~2 1/2" hole in the back of panel, unsecured of course. New panel is a Siemens combination meter/load center. I was hoping to bring all circuits through a similar hole in the back of the panel but I'm realizing this is not accepted. There is only one knockout in the back of the panel, and a small handful of varying sizes at the bottom. I'd like to keep the install clean from the exterior since it's a few feet away from the front door, so I'd like to come in through the back of the panel, but it would mean drilling like 20 holes for the two screw connectors where there are no k/o's. First question, is this accepted? And if so, what do folks do to allow for all those holes in the back against a wall?
Second option seems to be to run a raceway 18"-10' in length from top of panel, following rules below as I believe this situation is the exception. Next question is then, does this mean I can run an appropriately sized PVC/EMT conduit from the top of the panel and use a 90 or LB to penetrate the exterior wall to get into the interior, terminate that into a big fat j-box and properly secure (clamp) all of my romex/branch circuits into that j-box? In that case, do I have to junction the wires in the box, or can I simply use it as a passthrough into the raceway?
"All cables must be secured to the enclosure with fittings designed and listed for the cable [312.5(C)]. See 300.12 and 300.15.
Cable clamps or cable connectors must be used with only one cable, unless that clamp or fitting is identified for more than one cable. Some Type NM cable clamps are listed for two Type NM cables within a single fitting (UL White Book, product category PXJV).
Exception: Cables with nonmetallic sheaths aren't required to be secured to the enclosure if the cables enter the top of a surface-mounted enclosure through a nonflexible raceway not less than 18 in. or more than 10 ft long, if all of the following conditions are met:
(a) Each cable is fastened within 1 ft from the raceway.
(b) The raceway doesn't penetrate a structural ceiling.
(c) Fittings are provided on the raceway to protect the cables from abrasion.
(d) The raceway is sealed.
(e) Each cable sheath extends not less than ¼ in. into the panelboard.
(f) The raceway is properly secured.
(g) Conductor fill is limited to Chapter 9, Table 1 percentages (Figure)."
A long first post, I know, and I greatly appreciate any and all help you can give, cheers!
Posts I've read:
https://forums.mikeholt.com/forum/a...es-in-pipe-sleeve-into-breaker-panel?t=179892
https://www.electriciantalk.com/f9/nm-cable-through-back-surface-mount-panel-58938/
Among others...
I can post pictures later when I'm at the job but I'd like to get this out there because we're trying to get moving. I'm replacing an old exterior surface mounted 100A main panel with a new 200A main panel, old panel is fed from above and new panel will be fed from below once we run conduit from pole. Need to install new panel temporarily since we're running all of the siding right now, and don't want a big old extra hole where the old panel was.
Old panel has all branch circuits coming through a ~2 1/2" hole in the back of panel, unsecured of course. New panel is a Siemens combination meter/load center. I was hoping to bring all circuits through a similar hole in the back of the panel but I'm realizing this is not accepted. There is only one knockout in the back of the panel, and a small handful of varying sizes at the bottom. I'd like to keep the install clean from the exterior since it's a few feet away from the front door, so I'd like to come in through the back of the panel, but it would mean drilling like 20 holes for the two screw connectors where there are no k/o's. First question, is this accepted? And if so, what do folks do to allow for all those holes in the back against a wall?
Second option seems to be to run a raceway 18"-10' in length from top of panel, following rules below as I believe this situation is the exception. Next question is then, does this mean I can run an appropriately sized PVC/EMT conduit from the top of the panel and use a 90 or LB to penetrate the exterior wall to get into the interior, terminate that into a big fat j-box and properly secure (clamp) all of my romex/branch circuits into that j-box? In that case, do I have to junction the wires in the box, or can I simply use it as a passthrough into the raceway?
"All cables must be secured to the enclosure with fittings designed and listed for the cable [312.5(C)]. See 300.12 and 300.15.
Cable clamps or cable connectors must be used with only one cable, unless that clamp or fitting is identified for more than one cable. Some Type NM cable clamps are listed for two Type NM cables within a single fitting (UL White Book, product category PXJV).
Exception: Cables with nonmetallic sheaths aren't required to be secured to the enclosure if the cables enter the top of a surface-mounted enclosure through a nonflexible raceway not less than 18 in. or more than 10 ft long, if all of the following conditions are met:
(a) Each cable is fastened within 1 ft from the raceway.
(b) The raceway doesn't penetrate a structural ceiling.
(c) Fittings are provided on the raceway to protect the cables from abrasion.
(d) The raceway is sealed.
(e) Each cable sheath extends not less than ¼ in. into the panelboard.
(f) The raceway is properly secured.
(g) Conductor fill is limited to Chapter 9, Table 1 percentages (Figure)."
A long first post, I know, and I greatly appreciate any and all help you can give, cheers!
