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Vern Heiler
09-21-2011, 04:58 PM
Is there a maximum allowed bare wire at the breaker?

Jerry Peck
09-21-2011, 05:10 PM
Basically, yes.

The breaker will have a "strip gage" on it, typically molded into the side of the case, and that is the length the wire should be stripped back, and that length will provide the wire seating into the terminal and almost no extra stripped wire.

I've often heard that 1/4 inch is allowed, but I have not found that stated anyplace when I was looking for it (which was years ago, I have not looked for it in recent years).

Vern Heiler
09-21-2011, 05:17 PM
Thanks Jerry, I think I'll go out on a limb and call this too much.

Jerry Peck
09-21-2011, 05:20 PM
Thanks Jerry, I think I'll go out on a limb and call this too much.

Vern,

Instead of calling it too much was stripped, call it as "unsafe, this condition was caused by stripping the insulation back farther than necessary".

Rollie Meyers
09-22-2011, 02:24 PM
Thanks Jerry, I think I'll go out on a limb and call this too much.


There is enough insulation stripped back that you could cross the 2 conductors & short circuit them, your not going out on a limb, IMHO.

Vern Heiler
09-22-2011, 02:28 PM
There is enough insulation stripped back that you could cross the 2 conductors & short circuit them, your not going out on a limb, IMHO.
Even though I knew I was not going to touch or get shocked by them, I had that same feeling you get when an unloaded gun is pointed at you.

Jerry Peck
09-22-2011, 06:13 PM
There is enough insulation stripped back that you could cross the 2 conductors & short circuit them, your not going out on a limb, IMHO.

One slip of the screw driver anywhere near them and you could find out what an arc flash looks like (worst case) or do some arc welding (best case).

How do you make a long screw driver into a stubby? Hold it across those two wires ... :)

Bill Hetner
09-22-2011, 09:47 PM
that one is a good call to call out on. no limbs involed. that is just plain dangerous. someone messed up and any first year sparky could tell you that. looks like a diy job and someone didn't care enought to fix it right.

and thanks Jerry for the note of the strip gage. good imfo!!

Rollie Meyers
09-22-2011, 10:47 PM
Strip gauges are a underused aid, just look at how many poorly done cord caps & connectors there are that would have been done right if the installer had used the strip gauge.......:(

Jerry Peck
09-23-2011, 03:51 AM
Strip gauges are a underused aid, just look at how many poorly done cord caps & connectors there are that would have been done right if the installer had used the strip gauge.......:(

Yes, and a strip gage is molded into almost every receptacle, switch, etc., too. Probably look at any item with a terminal connection and you will find a strip gage.

Donald Kane
09-23-2011, 08:26 AM
NECA 1, cited in (2008) NEC, 110.12 FPN states that "Terminations of insulated conductors.....stripped length of bare conductor is not longer than required for the equipment terminal, lug or connector. The conductor insulation shall bear against the terminal or connector shoulder, but not extend into the terminator point." NECA 1 Chapter 9, section o

Donald W. Kane, PE

Jerry Peck
09-23-2011, 01:11 PM
NECA 1, cited in (2008) NEC, 110.12 FPN states that "Terminations of insulated conductors.....stripped length of bare conductor is not longer than required for the equipment terminal, lug or connector. The conductor insulation shall bear against the terminal or connector shoulder, but not extend into the terminator point." NECA 1 Chapter 9, section o

Donald W. Kane, PE

There we have it ... NO extra insulation is allowed to be trimmed off - and that makes sense too as the uninsulated conductor which is outside the terminal is a potential hazard, and Vern's photo shows an exaggerated example of the condition and why it is not allowed.

bob smit
09-23-2011, 03:55 PM
Your opinion is not enforceable although reasonable.
The strip gage length is enforceable per 110.3(b).
Whether a fuse block or breaker termination, most include a pocket of sorts that protect to some degree, incidental contact via a stray screwdriver or finger.
As an AHJ, I consider this 'pocket' to be the Manufacturers' listed intent in which to contain terminations. This of course is my opinion as to interpreting the intent of said pocket.