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Joined: Oct 2000
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OK then, maybe this would work:
A permit and plans have been submitted for a plan review and the AHJ begins that procedure, and in the specifications it states that "NEMA says we don't need the bushings", and I ask the question:
"Are you planning not to use bushings? You say, I plan on it anyway and I will use the bushings."
Some electricians have to wear the AHJ hat for a while, and that may come later after they tire from the cold, and climbing the ladder, and the dirt and sore back!
Bushings are required for AC but not for MC cable.
Joe Tedesco, NEC Consultant
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Joined: May 2002
Posts: 132
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If they have been deemed "not required" then why do the manufacturers still go through the trouble and cost of attaching a complimentary bag with each spool? Just curious??
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Joined: Jan 2003
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Tradition ![[Linked Image]](https://www.electrical-contractor.net/ubb/smile.gif) We would ask for them I actually had to buy some recently. I often grab up partly used 1000' spools from job close outs and all the red heads are gone.
Bob Badger
Construction & Maintenance Electrician
Massachusetts
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Joined: Nov 2002
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I wonder how many of us would feel comfortable about the job if we didn't use'em?
Russell
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Joined: May 2002
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As a unbiased comment to this thread, some manufacturers recomend using "anti short" bushings on MC regardless of code requirements. Now with that said, does this manufacturers "recomendation" mean anything or have any substance as far as liability is concerned?
Roger
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Joined: Feb 2003
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Remember about 10 years ago red devils where redesigned with the little points sticking up so inspectors could see them being used.
Every fault I have seen in an m/c install was do to the lack of not using a bushing!
It should be a code requirement, not a design issue!
Shoot first, apologize later.....maybe
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Joined: Sep 2001
Posts: 806
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I always use the redheads, but they often tend to fall out of the cable unless secured with a wrap of tape.
AC cable allows you to backwrap the bonding wire to secure the redhead...
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Joined: Jul 2003
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After all is said and done, the listings and code call for the use of "approved fittings" be used for termination. Most if not all AC fittings are not approved for terminating MC cable. MC fittings have a guide built in that hold the wire centered, away from the edge. AC connectors do not. The biggest problems I have seen analyzing failed industrial equipment have been 1)cutting MC or AC with improper tools; 2) using AC connectors with MC cable and no bushings; 3)failing to properly torque the termination fitting so that the cable pulls out. The next time you go to the supply house to get MC fitting, especially 90s, look and see exactly what you get. You might be surprized.
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Here is the text from NEMA statement on Anti-Short bushings that Joe and I referenced. You can download it from NEMA here. NEMA Bulliten 90 Use of Anti-Short Bushings (pdf) NEMA ENGINEERING DEPARTMENT BULLETIN No. 90
August 14, 2002
Use of Anti-Short Bushings for Terminating Type MC Cable
There has been much confusion within the Installation and Inspection communities regarding the use of anti-short bushings for terminating Type MC cable. The confusion stems from the fact that some MC cable manufacturers include anti-short bushings with their cable. The inclusion of anti-short bushings with coils or reels of MC cable is based on historical practice relating to the requirements of 320.40 of the NEC, which mandates the use of anti-short bushing or its equivalent protection for Type AC Cable.
Fittings used with Type MC Cable are required to be listed per 330.40 of the NEC. NEMA supports the use of listed fittings for MC Cable. The design of these fittings may or may not include an insulated throat however, they are required to be provided with a smooth, rounded end stop so that the metal sheath of the cable will not pass through and the wires will not be damaged in passing over the end stop. Whether or not an insulated throat is part of the listed product, these listed MC fittings do not require an additional anti-short bushing. Anti-short bushings that may be supplied by MC Cable manufacturers are for optional use by the installer, however they are not required.
ROP #7-116 from the May 2001 Report on Proposals (ROP) for the 2002 NEC was a proposal seeking to require anti-short bushings on all MC Cable termination installations.
The following is an excerpt from the Panel statement rejecting the proposal:
Anti-short bushings are not required for Type MC cable in accordance with the listing for the product. The termination fittings approved for use with Type MC cables are designed such that the wires will not come in contact with the cut edge of the armor; the throat of the fitting is small enough to prevent contact with the armor. Type MC termination fittings perform the same function for Type MC cable as Type AC terminations plus the anti-short bushing do for Type AC cable.
NEMA supports the uniform adoption and enforcement of the NEC and recommends that local Authorities Having Jurisdiction follow the requirements of NEC Section 330.40, Boxes and Fittings for MC Cable. Section 330.40 requires that the fitting be listed, but does not mandate the use of an anti-short bushing.
Distribution List:
Standards and Conformity Assessment Policy Committee
Codes and Standards Committee
NEMA Executive Staff
Bob Badger
Construction & Maintenance Electrician
Massachusetts
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Joined: Dec 2000
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I ALWAYS use them.
The hole in the fitting is for inspecting the required AC bushing.
ALWAYS use them, why not, they're FREE!!
...S
[This message has been edited by electure (edited 11-28-2003).]
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