Reuse of Installed Cable

[john_EE]

My cables were already installed in conduits, raceways but we intend to pull it and reinstall it somewhere. Those cables were never energized.

Is there any rule specific in NEC that I cannot reuse a cable after dismantling/pulling them? What section of NEC is that?

[Dennis Alwon]

I am unaware of any NEC that would not allow you to reinstall. As long as there is no damage to the wire I don't see why it would matter even if it were energized.

[Pierre C Belarge]

110.7 Wiring Integrity.
300.17 Number and Size of Conductors in Raceway.

This could possibly trigger a flag, with my requesting a megger test of the completed install of the conductors in the new raceway.


NYS has a section in the code requiring any used equipment to meet the current code standards at the current time of installation.


Check your local laws to see if you may have some similar or more restrictive requirements.

[john_EE]

Thanks Pierre and Dennis... 300.17 is helpful... I may be wrong but I have read it in NEC in exact sense... tsk tsk... i really forgot this article and section...

[infinity]

Who would actually know if you re-used some wire?

[JJWalecka]

Interesting….Technically I always thought that once conductors were installed they couldn’t be pulled and reused, not that it isn’t common practice.

Megging and checking for obvious discrepancies are logical before reuse.


JJ

[mdshunk]

If someone were to say that conductors cannot be reused (nobody's said that so far), they would also be saying that something fundamentally in the installation or reinstallation process damages conductors. If we were to belive that, the whole wired world is in a world of hurt. The same care that was taken to install the conductors originally can be taken in their removal. The conductors can also be re-installed with that same high level of care. I've reused many a conductor (particularly larger than #4), whether energized previously or not, I can attest that it is a sound practice. I would reiterate the suggestion that the conductors be meg'd. Meg them before removal from the old raceway, and meg them again after they're reinstalled in the new location.

[Dennis Alwon]

If someone were to say that conductors cannot be reused (nobody's said that so far), they would also be saying that something fundamentally in the installation or reinstallation process damages conductors. If we were to belive that, the whole wired world is in a world of hurt. The same care that was taken to install the conductors originally can be taken in their removal. The conductors can also be re-installed with that same high level of care. I've reused many a conductor (particularly larger than #4), whether energized previously or not, I can attest that it is a sound practice. I would reiterate the suggestion that the conductors be meg'd. Meg them before removal from the old raceway, and meg them again after they're reinstalled in the new location.


Well said Marc. I totally agree

[JJWalecka]

Meg em especially after they are half hitched a bunch of times and pulled out with an old Ford F150. LOL.

JJ

[mdshunk]

Meg em especially after they are half hitched a bunch of times and pulled out with an old Ford F150. LOL.

JJ
That's not how you remove conductors. That's how you install them. 8-)

[nakulak]

unless they are big conductors, then you use a dodge.

[e57]

Since this is in the LV area - I'll add this - there is/was a code about removing unused LV cabling. No codes on this computer or I would look it up.....

[infinity]

Even if conductors were removed and reinstalled I find no provision of the NEC that would require them to be megger tested. Does such a provision exist?

[mdshunk]

Even if conductors were removed and reinstalled I find no provision of the NEC that would require them to be megger tested. Does such a provision exist?
Of course not, but that's a requirement of sound electrical contracting.

[Pierre C Belarge]

Even if conductors were removed and reinstalled I find no provision of the NEC that would require them to be megger tested. Does such a provision exist?



110.7 Requires one to install conductors without short circuits, ground faults, or any connections to ground...
That is what inspectors may reference to request meggering.

[infinity]

110.7 Requires one to install conductors without short circuits, ground faults, or any connections to ground...
That is what inspectors may reference to request meggering.


IMO that's very weak and unenforceable. You could say that about any conductor in a conduit.

[Pierre C Belarge]

IMO that's very weak and unenforceable. You could say that about any conductor in a conduit.


Exactly...

[mdshunk]

IMO that's very weak and unenforceable. You could say that about any conductor in a conduit.
Yeah, but if I pulled in some medium voltage cable, would you throw the switch without testing? Heck, even 480 can make a mess.

[infinity]

Yeah, but if I pulled in some medium voltage cable, would you throw the switch without testing? Heck, even 480 can make a mess.


True, but most conductors are tested when the CB is turned on for the first time. If there's a problem you'll know then. :rolleyes:

[mdshunk]

True, but most conductors are tested when the CB is turned on for the first time. If there's a problem you'll know then. :rolleyes:
I know you're only joking, but stories abound of conductors that lasted for a short while, without being tested, after the breaker was turned on. Could be days, weeks, or months, but without testing you have no idea where you stand. The breaker might be on the razor's edge of a ground fault.

[Pierre C Belarge]

True, but most conductors are tested when the CB is turned on for the first time. If there's a problem you'll know then. :rolleyes:


That is not testing, that is taking a chance...which seems to be the way some in our industry have been introduced as to how it should be done.

I have been surprised as an inspector in regards to how many shops actually test prior to energizing circuits/feeders/services. It is more than I expected.

[quogueelectric]

I always drool when demoing parking lot pole lighting because I know I will not have to buy hot tub spa wire for a while. Usually 100' or better 4s 6s and 8s Cha Ching!!

[infinity]

When was the last time an electrician meggered every branch circuit before energizing them? Close to never. Like it or not the testing happens when the circuit is turned on for the first time.

[Pierre C Belarge]

I have been told that in Ireland, the inspectors megger the house as part of the inspection. ;)


Quog
Would you be adverse to your mechanic installing used brake shoes in your car?

One, you or him would not know the actual condition of the shoes, just as you may not know the actual condition of wiring you pull from one location and then save for another time.
These "unknowns" are what make me wonder...

[LarryFine]

Quog
Would you be adverse to your mechanic installing used brake shoes in your car?

One, you or him would not know the actual condition of the shoes, just as you may not know the actual condition of wiring you pull from one location and then save for another time.
These "unknowns" are what make me wonder...Wire doesn't physically wear during normal use, while brakes do.

How about comparing new to used plastic, glass, or metal parts.

[mdshunk]

Would you be adverse to your mechanic installing used brake shoes in your car?
Actually, if you get work done like a new wheel bearing, your mechanic will install (or rather, re-install) your used brake pads back on your car if they still have life left in them. Pretty normal thing to do. You wouldn't want to see the bill if they put back on new parts for everything they had to dismantle to get to what they were really working on.

[ptonsparky]

True, but most conductors are tested when the CB is turned on for the first time. If there's a problem you'll know then. :rolleyes:

Had a tech school instructor that said he loved working with 480 because mistakes were easy to find.

[76nemo]

I have been told that in Ireland, the inspectors megger the house as part of the inspection. ;)


Quog
Would you be adverse to your mechanic installing used brake shoes in your car?

One, you or him would not know the actual condition of the shoes, just as you may not know the actual condition of wiring you pull from one location and then save for another time.
These "unknowns" are what make me wonder...


Ever read up on British compliance? We have it easy here.

[weressl]

When was the last time an electrician meggered every branch circuit before energizing them? Close to never. Like it or not the testing happens when the circuit is turned on for the first time.

In industry Meggering cables are a MUST and reports are filed. Using the breaker to 'test' the wiring is inexcusable. The MCB's are built for one single full fault after which they should be replaced as per manufacturers directives.

There is a much greater chance of the conductors being damaged while pulling out as there is no lubricant AND the dried lubricant is in the conduit that produces additional resistance. Its a case-by-case decision and the cable should be Megger-ed both after pulled out and after pulled into the new location. Visulal observation while the conductors are coming out also helpful to find weakened spots on the insulation that do not show up on the Megger but could become troublesome later on.

[infinity]

Using the breaker to 'test' the wiring is inexcusable.



I'm not making a judgment as to whether or not it's right or wrong but that is SOP for most of the world. If we put up a poll as to how many residential/commercial electricians megger their branch circuits before they turn on the CB's I would think that the poll would show that almost none do. :rolleyes: