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Adding a sub-panel, feeder question

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skeer

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Standish, MI Area
I realize this question has been asked a lot around here, but after searching I couldn't find my exact scenario. So briefly here it is, adding a sub-panel about 1 foot from the main panel in my basement. I have 100a service to the main, wanting to feed say 60 a to the sub, it's a Siemens 120a 12 position.

I mounted it on the wall on 3/4 plywood like the main panel is and my questions are:

Do I need to run the feeder in conduit or in any fittings?
Do exiting circuits needs to be in clamp fittings?
As for feeder cable, I have 4ga AL and 4ga (fine strange) copper, will either work?
Lastly, I assume it needs it's own ground that's clamped onto the ground rod where the main panel's is.. not tied 'to' the main ground wire yeah?


Thanks!
(pic attached)
((I did NOT wire the OG panel.. but I am planning on cleaning that mess up))
 

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wyliesdiesels

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Modesto, CA
skeer said:
Do I need to run the feeder in conduit or in any fittings?
Click to expand...
depends on the type of wire you use. if SER then no. If individual conductors then yes
skeer said:
Do exiting circuits needs to be in clamp fittings?
Click to expand...
again depends on the wire. if NM-b then yes....
skeer said:
As for feeder cable, I have 4ga AL and 4ga (fine strange) copper, will either work?
Click to expand...
60a circuit needs #6 cu or #4 AL.... fine stranded cu sounds like cordage which is not to be used for permanent building wiring... but why would you feed it only 60a? seems like a waste...
skeer said:
Lastly, I assume it needs it's own ground that's clamped onto the ground rod where the main panel's is.. not tied 'to' the main ground wire yeah?
Click to expand...
no requirement to connect to ground rods since main is in same building.

you do however need a 4-wire feeder with isolated neutral in subpanel. if you look at the electrical FAQs this question is answered there
skeer said:
Thanks!
(pic attached)
((I did NOT wire the OG panel.. but I am planning on cleaning that mess up))
Click to expand...
a mess it is.... what is up with the white conductors?
 
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skeer

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Zeke said:
That's interesting. I wonder if that is to monitor so as to balance the load? I'd like to know more.
Click to expand...
Yup it's the Emporia Energy monitor off Amazon. It uses a mobile app to display per circuit power usage. I bought it primarily to help compare the furnace fan motor, water heater and Oven for whenever we replace them. Wife wants an air fryer oven, I've got a bearing going out in the furnace motor so I'll replace it with one of the drop-in ECM motors like an Emerson Rescue. There's a couple others I just can't remember atm. And the water heater for when I replace it with a heat pump variant.
 
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skeer

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wyliesdiesels said:
So admittedly I had to google a few of these..
Click to expand...


wyliesdiesels said:
depends on the type of wire you use. if SER then no. If individual conductors then yes
Click to expand...
So the 4ga AL cable I have is likely SER however it's individual cables not enclose by a common sheathing.
wyliesdiesels said:
again depends on the wire. if NM-b then yes....
Click to expand...
Nope not this.. however I asked because the main panel has those threaded clamp connector for every branch circuit drop entering the enclosure.
wyliesdiesels said:
60a circuit needs #6 cu or #4 AL.... fine stranded cu sounds like cordage which is not to be used for permanent building wiring... but why would you feed it only 60a? seems like a waste...
Click to expand...
The copper cable I have is left over from the car audio days, solid copper, fine stranded, thick sheathing. I assumed it wouldn't be up to code but it's big so I figure it was worth asking. And for the 60 amp.. I have no reason for that really aside from still thinking of what I plan on powering the sub with is all. I could throw a 100 amp breaker in there to feed it, no reason not to I guess unless teh cost from 50-60 to 100 is astronomical.
wyliesdiesels said:
no requirement to connect to ground rods since main is in same building.

you do however need a 4-wire feeder with isolated neutral in subpanel. if you look at the electrical FAQs this question is answered there
Click to expand...
Isolated Neutral.. ahh so removing the bonding screw then. I had to go ohm things out not realizing that was it's just.. to tie Neutral to ground. I wound up finding a similar post here: https://www.garagejournal.com/forum/threads/wiring-a-detached-garage.340478/ Guy wiring up a subpanel out in his garage where you went over some of the same things esp regarding the neutral and grounds.
So my feeder will be hot/hot/neutral/ground. Does it matter that Neutral and Ground are bonded in the main panel? And if I understand the grounding correctly, since it's in the same building, since the feeder contains a ground the sub will use mains rod?
wyliesdiesels said:
a mess it is.... what is up with the white conductors?
Click to expand...
Emporia Energy Monitor: https://www.emporiaenergy.com/how-the-vue-energy-monitor-works
 
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wyliesdiesels

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Modesto, CA
skeer said:
So the 4ga AL cable I have is likely SER however it's individual cables not enclose by a common sheathing.
Click to expand...
cant be.... SER has an outer sheath

skeer said:
Nope not this.. however I asked because the main panel has those threaded clamp connector for every branch circuit drop entering the enclosure.
Click to expand...
if it isnt NM-b aka Romex then what type of wire do you have? MC or BX/AC would be the only other type that uses clamp connectors...

skeer said:
The copper cable I have is left over from the car audio days, solid copper, fine stranded, thick sheathing. I assumed it wouldn't be up to code but it's big so I figure it was worth asking.
Click to expand...
Definitely not kosher to use for building wiring.... not anywhere near the same wire....dont use that...

skeer said:
And for the 60 amp.. I have no reason for that really aside from still thinking of what I plan on powering the sub with is all. I could throw a 100 amp breaker in there to feed it, no reason not to I guess unless teh cost from 50-60 to 100 is astronomical.
Click to expand...
you would need larger wire if you went with a 100a feeding breaker.... #3 cu or #1 al

skeer said:
Isolated Neutral.. ahh so removing the bonding screw then. I had to go ohm things out not realizing that was it's just.. to tie Neutral to ground. I wound up finding a similar post here: https://www.garagejournal.com/forum/threads/wiring-a-detached-garage.340478/ Guy wiring up a subpanel out in his garage where you went over some of the same things esp regarding the neutral and grounds.
Click to expand...
yes isolated neutral... remove bonding screw or strap

skeer said:
So my feeder will be hot/hot/neutral/ground. Does it matter that Neutral and Ground are bonded in the main panel?
Click to expand...
nope doesnt matter and the main panel is where you want them bonded.

skeer said:
And if I understand the grounding correctly, since it's in the same building, since the feeder contains a ground the sub will use mains rod?
Click to expand...
EGC/grounds and grounding electrodes are not the same animal... they serve different functions... never confuse the 2 as being the same..... I have a post in the electrical FAQ sticky thread that goes over this

but yeah no rods needed on sub since its in the same building as the main...
 
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skeer

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Thanks @wyliesdiesels The advice is much appreciated. So all Home Depot had was a 60 double pole so I grabbed that, also their selection of non-metallic is horrible! I brought home the 60 breaker and two 1" female/male threaded adapters for entry/exit for teh feeder cables. They did not have the right fittings to complete the conduit so I went looking at the Michigan electrical codes. It appears that PVC (Rigid Polyvinyl Chloride) is allowed for feeders: MI Codes So I do have plenty of that I can use to finish this. If their usage of PVC is not the same as typical sch 40 plumbing pvc then I will swap it out later. There's not but two non-critical branch circuits that are going to be off this sub-panel for a while.

Also understood on the cable, I've plumbed through the feeders.. on BTW this is the cable I have: al xlpe
 
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skeer

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Weird it let's me right in..​


E3801.2 Allowable Wiring Methods​


The allowable wiring methods for electrical installations shall be those listed in Table E3801.2. Single conductors shall be used only where part of one of the recognized wiring methods listed in Table E3801.2. As used in this code, abbreviations of the wiringmethod types shall be as indicated in Table E3801.2. [110.8, 300.3(A)]

TABLE E3801.2
ALLOWABLE WIRING METHODS
ALLOWABLE WIRING METHODDESIGNATED
ABBREVIATION
Armored cableAC
Electrical metallic tubingEMT
Electrical nonmetallic tubingENT
Flexible metal conduitFMC
Intermediate metal conduitIMC
Liquidtight flexible conduitLFC
Metal-clad cableMC
Nonmetallic sheathed cableNM
Rigid polyvinyl chloride conduit (Type PVC)RNC
Rigid metallic conduitRMC
Service entrance cableSE
Surface racewaysSR
Underground feeder cableUF
Underground service cableUSE

​

​

E3801.4 Wiring Method Applications​


Wiring methods shall be applied in accordance with Table E3801.4. (Chapter 3 and 300.2)

TABLE E3801.4
ALLOWABLE APPLICATIONS FOR WIRING METHODSa, b, c, d, e, f, g, h, i, j, k, l
ALLOWABLE APPLICATIONS
(application allowed where marked with an "A")		ACEMTENTFMCIMC
RMC
PVC		LFCaMCNMSRSEUFUSE'
Services-AAhAiAAiA--A-A
FeedersAAAAAAAA-AbAAb
Branch circuitsAAAAAAAAAAcA-
Inside a buildingAAAAAAAAAAA-
Wet locations exposed to sunlight-AAh-AAA--AAeAe
Damp locations-AAAdAAA--AAA
Embedded in noncinder concrete in dry location-AA-AAj------
In noncinder concrete in contact with grade-AfA-AfAj------
Embedded in plaster not exposed to dampnessAAAAAAA--AA-
Embedded in masonry-AA-AfAA-----
In masonry voids and cells exposed to dampness or below grade line-AfAAdAfAA--AA-
Fished in masonry voidsA--A-AAA-AA-
In masonry voids and cells not exposed to dampnessAAAAAAAA-AA-
Run exposedAAAAAAAAAAA-
Run exposed and subject to physical damage----Ag-------
For direct burial-Af--AfAAf---AA
For SI: 1 foot = 304.8 mm.
  1. Liquid-tight flexible nonmetallic conduit without integral reinforcement within the conduit wall shall not exceed 6 feet in length.
  2. Type USE cable shall not be used inside buildings.
  3. The grounded conductor shall be insulated.
  4. Conductors shall be a type approved for wet locations and the installation shall prevent water from entering other raceways.
  5. Shall be listed as "sunlight resistant."
  6. Metal raceways shall be protected from corrosion and approved for the application. Aluminum RMC requires approved supplementary corrosion protection.
  7. RNC shall be Schedule 80.
  8. Shall be listed as "sunlight resistant" where exposed to the direct rays of the sun.
  9. Conduit shall not exceed 6 feet in length.
  10. Liquid-tight flexible nonmetallic conduit may be encased in concrete where listed for direct burial and only straight connectors listed for use with LFNC are used.
  11. In wet locations under any of the following conditions
    1. The metallic covering is impervious to moisture.
    2. A lead sheath or moisture -impervious jacket is provided under the metal covering.
    3. The insulated conductors under the metallic covering are listed for use in wet locations and a corrosion-resistant jackets is provided over the metallic sheath.
  12. Type USE cable not permitted above ground except to terminate at the exterior of a building in an approved enclosure and protected in accordance with Section E3803.3.
 
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dave*99

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skeer said:
Thanks @wyliesdiesels The advice is much appreciated. So all Home Depot had was a 60 double pole so I grabbed that, also their selection of non-metallic is horrible! I brought home the 60 breaker and two 1" female/male threaded adapters for entry/exit for teh feeder cables. They did not have the right fittings to complete the conduit so I went looking at the Michigan electrical codes. It appears that PVC (Rigid Polyvinyl Chloride) is allowed for feeders: MI Codes So I do have plenty of that I can use to finish this. If their usage of PVC is not the same as typical sch 40 plumbing pvc then I will swap it out later. There's not but two non-critical branch circuits that are going to be off this sub-panel for a while.

Also understood on the cable, I've plumbed through the feeders.. on BTW this is the cable I have: al xlpe
Click to expand...
Do you mean white PVC plumbing pipe? Don't use that. Use gray electrical PVC conduit.
 
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skeer

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Location
Standish, MI Area
alfredeneuman said:
It's not. Just buy the correct material for the job. You said yourself that it was "about a foot" away. Just a foot could be accomplished for under $2
Click to expand...
You;d think it could. Just mentioning this for clarity but not b/e it's some impairing cost factor. Nearest sources for conduit for me, min cost to run the 1 1/4 conduit with elbow and screw fittings: ~$30. But, to be fair, this area ***** hard in all aspects.
 
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alfredeneuman

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