SER or not?

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Smart $

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Ohio
BTW, it sounds like you're talking about top-down installations. It'd be a little different for bottom-up installations, right?
 
Wow, this is great! Thanks. To follow up I'll say that no, there is no copper in the house, or building steel for that matter. I will definitely drive 2 ground rods and will also scrub the idea of using the LB and instead use an 8x8x4 PVC JB. Also, yes, the entrance into the building would only be a stub into the joists and then free cable up into the panel one flight up. It's a modular home and already has a 2" PVC sleeve from the "basement" sacrifice floor up into the panel. But if I use SER (AL 4/0) cable with an outer jacket, 3 insulated conductors and a bare ground, how would I correctly use the ground in the cable from the panel on the "2nd" floor all the way to the Ground rod? I do understand that certain utility providers may have a preference, but of course the AHJ supersedes and I would like to know about providing the ground from the panel to the ground rod as I know this is more often preferred over bonding at the service disconnect (non-fused). Again, much thanks.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
IMO, it would be easier - if possible- to just pipe to the panel. I do this all the time rather than switch over or fight se cable inside conduit
 

augie47

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Location
Tennessee
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State Electrical Inspector (Retired)
Sounds like we may be swallowing the elephant and gagging on a gnat :)
Before you ever get to that LB, is there any overcurrent protection at the meter ?
It appears you have a long run on the interior of the house and I missed any mention of an OCP before the 2nd floor.
 

Smart $

Esteemed Member
Location
Ohio
... But if I use SER (AL 4/0) cable with an outer jacket, 3 insulated conductors and a bare ground, how would I correctly use the ground in the cable from the panel on the "2nd" floor all the way to the Ground rod? I do understand that certain utility providers may have a preference, but of course the AHJ supersedes and I would like to know about providing the ground from the panel to the ground rod as I know this is more often preferred over bonding at the service disconnect (non-fused). Again, much thanks.
You can't have a non-fused service disconnect and remote overcurrent protection (OCP). Has to either be a fused disconnect or non-fused with OCP immediately adjacent thereto.

The service disconnect is also where service neutral and EGC system are bonded (main bonding jumper). Where the service neutral is a lateral, you have to connect your GES system to the neutral in the disconnect or meter pan (POCO rules apply here in addition to NEC). Neutral and EGC are isolated from each other after service disconnect. Can't connect GEC's on load side either.
 

ritelec

Senior Member
Location
Jersey
Not sure what you mean by 'deflection formulas'.

Conduit fill is simply 53%. Cable area is pi*D?/4, where D is the widest cable dimension.

You also have pull requirement(s) of 314.28.

***
I suppose I should have mentioned this earlier, but we could make the LB a moot discussion if OP just terminates the PVC at one of the sill plate covers posted by iwire. Bending radius requirement must still be met, but shouldn't be a problem with a full size, perhaps even slotted hole under the sill plate cover.

Cable area is pi*D?/4..............wow, ok ???? lol

I got 4/0 3w with a 2/0 to be 1496 mils , 1496x1496= 2238016 x .0000007854 = 1.7577 (inches squared)

2.5 " pvc @ 53% = 2.488
3" pvc @ 53% =3.852

I can sleep in peace tonight. (if my wife and dog don't snore which I doubt).
 
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Little Bill

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Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
Wow, this is great! Thanks. To follow up I'll say that no, there is no copper in the house, or building steel for that matter. I will definitely drive 2 ground rods and will also scrub the idea of using the LB and instead use an 8x8x4 PVC JB. Also, yes, the entrance into the building would only be a stub into the joists and then free cable up into the panel one flight up. It's a modular home and already has a 2" PVC sleeve from the "basement" sacrifice floor up into the panel. But if I use SER (AL 4/0) cable with an outer jacket, 3 insulated conductors and a bare ground, how would I correctly use the ground in the cable from the panel on the "2nd" floor all the way to the Ground rod? I do understand that certain utility providers may have a preference, but of course the AHJ supersedes and I would like to know about providing the ground from the panel to the ground rod as I know this is more often preferred over bonding at the service disconnect (non-fused). Again, much thanks.

The ground in the cable is the EGC. You can't land an EGC on a ground rod. The EGC will land on the ground bar in the panel. You need a GEC (grounding electrode conductor) to run to the ground rod. That is usually a bare solid copper conductor but can be stranded. It can also be Aluminum under certain conditions. That will either terminate to the grounded/neutral lug in the meter or neutral buss in the panel. Can even go to the weatherhead and crimped onto the neutral there if your POCO allows that.

But you never run a 4-wire (2 hots, neutral, grounding conductor) from the service meter. You would just run a 3-wire (2 hots & neutral) from meter to the first disconnect w/ocp. Now if you have a disconnect outside with OCPD, that is your first disconnect and you run 3-wire from meter to there. From the disconnect to any other panel is where you would run the 4-wire that contains the EGC (grounding wire). The panels after the first means of disconnect are subpanels and must be wired accordingly.
 

Jgreagori

Member
Location
South Jersey
Catching this at the end but..Yes to fused disconnect outside adjacent electric meter. SER to the panel inside the modular home (however you get there.) e sure to bond the neutral bar to the disconnect. Grounding electrode conductor #6 from your fused disconnect to two ground rods 5/8 x 8Ft. Don't forget you will have to separate grounds and neutrals in the panel installed inside the house and also remove the bonding screw. Also check with the AHJ about the correct mounting height for the service equipment as it relates to the flood DFE (design flood elevation). In south jersey where i am inspecting it is a concern to have the main switch out of flood but the meter requirements are up to the the power company.
 
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