High level sub-panel circuit shuffle brainstorm

[pods8 (Rugged Stitching)]

If you can prove your load is sufficient for the 150amp main, then a sub panel won’t hurt anything just make sure you label everything very clearly. Move some loads over to the sub panel add a feed.

A critical loads panel is not a bad idea I have done this for people who wanted everything separated for ease of recognition to them as to what can be run on the genset.

As noted I need to audit the full 12mo of smart meter data if moving forward but I can't find any 15min periods over 2kwh yet (which is <40amps unless I am mistaken).

I'm not concerned about doing the work. Other than identifying any nuances for compliance the wiring and moving things is no issue. I've rewired all the aluminum home runs on a previous house, etc.

The critical panel is just a convenient overlap of needing more capacity. Also it allows me to only move 120V circuits into it which I can power up with the 120V generator I currently have (again idiot proof for someone not trying to power 240V circuits off a 120V generator). I will need to be strategic about which circuits I place where because only 1 leg will be powered up by that 120V generator but later someone could use a 240V generator no problem, they'd just need to put in a different input plug. Additionally I need to be selective about how I move circuits also because a handful of the original wiring was done with 12-3 NM feeding two different circuits (on different legs) with a shared neutral. I don't like that it was done that way but its not worth messing with, I just need to keep the circuits on different legs still.

Point is I'm aware of what is needed and involved in terms of fundamentals. I just will need to do homework on code compliance items. I also don't know off hand if my AHJ would require changing breakers to AFCI and/or GFCI when doing this or not, the circuits aren't changed and I would be extending the input wiring <6'. In some cases I don't know that I physically need to extend the wiring (it would probably reach into the new panel) but that would mean running NM wires between boxes which I'm not sure is allowed. NM isn't supposed to be outdoors but obviously they allow it coming into the outdoor panel here, not sure how they view it if they wiring could reach the new panel as is or if no matter what I need to splice in UF or THHN wires.

 

[BLJ]

Best advice I could give you.

LABEL LABEL LABEL, make life a lot easier

A man after my own heart………

 

[pods8 (Rugged Stitching)]

Best advice I could give you.

LABEL LABEL LABEL, make life a lot easier

I got a label maker.

 

[BLJ]

In reference to your wire jacket question. Are you planning to use conduit between the main panel and sub?

 

[pods8 (Rugged Stitching)]

In reference to your wire jacket question. Are you planning to use conduit between the main panel and sub?

I assumed there would have to be a couple inches of it unless there is a legal way to butt them together with a sealed opening that isn’t considered “conduit”. One of those nuance questions.

 

[BLJ]

I misinterpreted what you wrote.

I thought you were going to free air Romex between the boxes.

You can use a small section of pipe or use a chase nipple between the two.
With the chase you should be able to get them to touch. If space is a concern.

 

[pods8 (Rugged Stitching)]

I misinterpreted what you wrote.

I thought you were going to free air Romex between the boxes.

You can use a small section of pipe or use a chase nipple between the two.
With the chase you should be able to get them to touch. If space is a concern.

Space isn’t a concern. It’s what the AHJ would or wouldn’t allow to route NM between boxes or not. It may be that no matter what I have to splice even if the NM could reach through a couple of inches of chase. Not sure yet.

 

[BLJ]

I think I’m tracking now.

If you do have to splice, I would probably have to recommend THHN between the two boxes since it will be in conduit.
I would assume that this would be what the AHJ would want as well.

I’ve read (not researched myself) the debate about Romex in conduit. Some yes, some no, some depends on AHJ in different city/state.

I will say that THHN in conduit will be correct.
Romex may be “iffy”. IMO.

 

[pods8 (Rugged Stitching)]

I think I’m tracking now.

If you do have to splice, I would probably have to recommend THHN between the two boxes since it will be in conduit.
I would assume that this would be what the AHJ would want as well.

I’ve read (not researched myself) the debate about Romex in conduit. Some yes, some no, some depends on AHJ in different city/state.

I will say that THHN in conduit will be correct.
Romex may be “iffy”. IMO.

Correct. I just don't know if the AHJ would allow it if it reached on its own rather than introducing a splice. The already allow NM in outdoor pain panels here (IE all the homeruns don't start as THHN and then splice to romex on the interior of the house) so there is some allowance for the matter. Its not a major issue either way its just a question to address with them if moving forward.

My plan if going with the critical loads panel is map put what circuits I want to move including which leg to land them on, identify part numbers for all the components and go in an talk to permitting and make sure they're happy with the plan.

The main point of this thread is if others had other ideas for consideration that I may not have considered.

 

[BLJ]

Not that my opinion amounts to anything, but I feel like you’re pretty squared away with your approach.

Be safe and keep the AHJ satisfied and I think you’ll be fine.