Service-Entrance Cable (SER)

Hi, came across a job last week where a customer had a splice box on outside wall with LFNC (about 5ft) going out straight to generator. Turns out customer wanted the cables buried. An 18” trench was dug and 1” PVC was used to run SE Stye R XHHW-2 (ground was bare) along with control wires (18 AWG 7 Type TC DIR BUR).
I was told that if jacket on XHHW-2 is taken off, it can get buried (Jacket was taken off). As I read the code 338, I’m not finding that SER is okay to bury unless TYPE USE is used. As for the control wire, jacket is rated 600v. Any insight is greatly appreciated. Thanks.
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Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Ser is not permitted to be installed underground even if it is in conduit. The bare aluminum cable is the issue, I believe.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
I think the flex connectors are usually shipped with the generators. Or do you not like the way it's installed??
I would have liked to see it come up out of the ground right next to the pad. That's prone to damage. I would put an elbow facing down on the inlet of the generator and form the flex into a U back up to a 90 on the supply keeping it close to the unit. Better, I would have piped it without the flex.

-Hal
 

retirede

Senior Member
Location
Illinois
I would have liked to see it come up out of the ground right next to the pad. That's prone to damage. I would put an elbow facing down on the inlet of the generator and form the flex into a U back up to a 90 on the supply keeping it close to the unit. Better, I would have piped it without the flex.

-Hal
I had always thought the manufacturers wanted the flex for vibration isolation.
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
I had always thought the manufacturers wanted the flex for vibration isolation.
It looks like what you have is the "corrugated metal flex tube" that is not listed for vibration, it will break under constant movement, only intended for allowance to move for installation alignment. For purposes you state of intent you would need something like this from generac, it comes in different lengths and used to isolate the gen vibration from the rest the gas line.
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Eddie702

Licensed Electrician
Location
Western Massachusetts
Occupation
Electrician
It looks like what you have is the "corrugated metal flex tube" that is not listed for vibration, it will break under constant movement, only intended for allowance to move for installation alignment. For purposes you state of intent you would need something like this from generac, it comes in different lengths and used to isolate the gen vibration from the rest the gas line.
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I just helped my co-worker install a Generac. It came with the corrugated metal flex shown in the OPs picture
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
I just helped my co-worker install a Generac. It came with the corrugated metal flex shown in the OPs picture
Well, there is a reason they are called Junkerac. :p I wouldn't expect them to know plumbing issues. If you install it like I said it would eliminate any vibration issues but as Fred said, I would be concerned about the vibration causing it to fail.

-Hal
 

hillbilly1

Senior Member
Location
Atlanta,Ga
Occupation
Field coordinator/ technical support
Generac had an issue years ago with the cheap plastic flex gas line they sent with the generator, after a while in the weather, it would deteriorate and crack. Also, generator looks a little too close to that basement window. If it was originally up against the house, it was definitely too close.
 
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