Confusion with SE/USE/SER/SEU

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I posted this question elsewhere and got one response to the effect of "because it is", but I'm looking for something more concrete.

In another thread running SEU cable inside/outside/inside to feed a attic furnace is being discussed. I am studying for my Journeyman's license so I've been trying find all these code issues on my own.

While researching the question, I looked in 338 and found that type SE could not be used for outdoor branch circuits and it had to be protected from physical damage. Type USE could not be used to feed an indoor circuit. However, I do not see type SEU specifically listed.

I have looked elsewhere (on the internet) to see if type SEU is rated to be outside, and in other parts of the country (I'm in WI) it is common to run SEU exposed for the service...see picture below.

SEU service.jpg

My confusion is as follows:
1) If this cable falls into the category of type SE cable, how is it not subject to physical damage?
2) If this cable falls into the category of type USE cable, how does it not violate 338.12 B 2?
3) (and most likely) If this cable does not fit in either of the categories, where can I find the section of the code that talks about type SEU cable?


 

acrwc10

Master Code Professional
Location
CA
Occupation
Building inspector
Thanks for that...that does clear some stuff up, but not how the picture posted is legal. Sure looks to me that that SEU is subject to physical damage.

From what? A plane, a weed wacker, or an ax wielding crazy person?
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
Thanks for that...that does clear some stuff up, but not how the picture posted is legal. Sure looks to me that that SEU is subject to physical damage.

I agree with that. I put mine in conduit, above and below(if not out the back).
 
From what? A plane, a weed wacker, or an ax wielding crazy person?

The first thing I thought of was a kid outside swinging a shovel or rake around. How bout animals? You said it yourself...a weed wacker.

300.5 d 1 requires underground conductors emerging from earth to be protected by enclosures or raceways to 8' above grade, and theoretically these undergrounds are protected by an OCD.
 

Gac66610

Senior Member
Location
Kansas
We are not allowed to use SEU for the mast, we can use SER to feed the panel but only if it penetrates the house form back of box and is less the 3ft inside (NE Kansas)
 

acrwc10

Master Code Professional
Location
CA
Occupation
Building inspector
It all comes down to "its a local AHJ call". Around here all service risers, overhead and underground, need to, be in conduit. No SER, no USE on the line side of the service. But I use SER all over the house on feeders and branch circuits, on anything I can, just like NM, but only on 40amps and up. The price is one third that of copper and in 35 years I have yet to see AL fail where CU would not have also failed.
 

kwired

Electron manager
Location
NE Nebraska
From what? A plane, a weed wacker, or an ax wielding crazy person?

Even if you run it in GRC it might be subject to physical damage - but might just take a little bit more abuse than the SE cable will take. Especially when it comes to a plane or an ax wielding crazy person:happyyes:
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
As I mentioned in the other forum. SE cable is comprised of SEU- service entrance ungrounded or 3 wire cable - 2 insulated one uninsulated and ser service entrance round- which is 3 insulated and an uninsulated wire.

I agree that there may be local amendments and we rarely see se cable here except as a riser for temp. poles or feeders but it is listed for outdoor. The fitting used is the appropriate protection going thru the wall.

BTW- here is a list of our forum acronyms--
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
K-Buz,

SER and SEU are types of SE cable. The picture you posted appears to be depicting service conductors, not branch circuits.

Branch circuits are permitted to be installed on the surfaces of buildings, it says it's not permitted unless it complies with Article 225. 225.10 permits multiconductor cable to be attached to the surface of a building.

Looking at your service conductors, the code that could be cited to reject the installation is 338.12(A)(1) or 230.50(A) - which feature the phrase "subject to physical damage" and are always in the eye of the beholder, which in this case is the AHJ. All wiring methods are prohibited from being installed where subject to physical damage, to one degree or another.

On the east coast, they do not see a threat to the SER in your picture. In other areas, they do. That type of install is not permitted in my area.

230.70(A)(1) does not specify a distance for outside or "inside nearest the entry of service conductors", so it again becomes an AHJ call for how close is close enough. In my area, I would expect to see a panel on the other side of that penetration into the building. In other areas there may be more leeway, and in others an outside service disconnect could be required.
 
I posted this question elsewhere and got one response to the effect of "because it is", but I'm looking for something more concrete.

In another thread running SEU cable inside/outside/inside to feed a attic furnace is being discussed. I am studying for my Journeyman's license so I've been trying find all these code issues on my own.

While researching the question, I looked in 338 and found that type SE could not be used for outdoor branch circuits and it had to be protected from physical damage. Type USE could not be used to feed an indoor circuit. However, I do not see type SEU specifically listed.

I have looked elsewhere (on the internet) to see if type SEU is rated to be outside, and in other parts of the country (I'm in WI) it is common to run SEU exposed for the service...see picture below.

View attachment 6603

My confusion is as follows:
1) If this cable falls into the category of type SE cable, how is it not subject to physical damage?
2) If this cable falls into the category of type USE cable, how does it not violate 338.12 B 2?
3) (and most likely) If this cable does not fit in either of the categories, where can I find the section of the code that talks about type SEU cable?



I pity the unsuspecting firefighter that hits an unprotected, unfused, melting installation like this with a hose stream.

Can you say "big kaboom!" :(
 

kwired

Electron manager
Location
NE Nebraska
I pity the unsuspecting firefighter that hits an unprotected, unfused, melting installation like this with a hose stream.

Can you say "big kaboom!" :(

Why?

They likely have pulled the meter at very least shortly after arriving, If the riser is in major involvement in the fire, the drop may already be laying on the ground. Electircity does not conduct (especially 120 volts) very well through a mist or spray - needs to be solid stream - which wastes a lot of water when fighting a fire, and they are wearing PPE that may not have electrical rating yet I would think is pretty effective at only 120 volts. And I don't know what is going to go kaboom.
 
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