What's the legality of lopping the NEMA connector off of the power cord of a UL-listed appliance and hardwiring it?
Specifically, I have an abandoned 15A 3-phase 208Y/120 disconnect switch that's all hooked up and ready to go- 3 free 120V circuits! Can I just lop the plug off the cord of a 115V power strip (or 3) and hardwire it to 1 phase of the disco switch? And yes, I'm well aware of the "right" way to do it, and there are various (admin & $$$) reasons I'm under pressure to do it with no-cost...
How will you keep the neutrals and grounds separate?
Tell them the truth ... you're not an electrician, they should get one to do it right.
Cut the end of the cord off and you violate the listing.
There are legal and ecenomic ways to take advantage of those 3 circuits in a handy location but it is clear from your question that you don't know enough about the circuit to do it right or safe. Call an electrician.
For various OPSEC reasons, I don't really want to go into why we don't "just do it right"- sufficed to say it would cost $5k to nipple a handy box to this switch to plug a power strip into, and despite stereotypes, some of us gumment types ARE interested in minimizing waste! I'm a PE and have AHJ authority here and losing the UL listing on a $20 power strip doesn't bother me in the least. I wasn't sure if replacing the plug was allowed for in listings or not, as hardwiring plugs seems to be a common practice, legal or not.
As to keeping the neutrals and grounds separate, I don't see the issue? I'd bond the grounds, bond the neutrals together and there shouldn't be any issues. Simple multiwire circuit with a shared neutral- no GFCI or AFCI to worry about.
400.8 says flexible cords can not be used as a substitute for fixed wiring. As soon as you hard wire the plug-strip I would consider it "fixed".
Replacing "molded" plugs does not change the UL Listing, however it may make the product unsuitable for performing its function. It is always up to the AHJ to accept or reject a product, the UL label just helps in the process.
From UL.com
What happens to the Listing if a UL-Listed product is modified in the field?
An authorized use of the UL Mark is the manufacturer's declaration that the product was originally manufactured in accordance with the applicable requirements when it was shipped from the factory. When a UL-Listed product is modified after it leaves the factory, UL has no way to determine if the product continues to comply with the safety requirements used to certify the product without investigating the modified product. UL can neither indicate that such modifications "void" the UL Mark, nor that the product continues to meet UL's safety requirements, unless the field modifications have been specifically investigated by UL. It is the responsibility of the Authority Having Jurisdiction (AHJ) to determine the acceptability of the modification or if the modifications are significant enough to require one of UL's Field Engineering Services staff members to evaluate the modified product. UL can assist the AHJ in making this determination.
If a party wishes UL to determine if the modifications made to a UL Listed product comply with UL requirements, the appropriate Field Engineering Service can be initiated to investigate the modifications. This investigation will only be conducted after UL consults with the AHJ to assure that UL's investigation addresses all areas of concern and meets all of the AHJ's needs.
Ah, and age old "(1) As a substitute for the fixed wiring of a structure." that is oft considered to declare extension cords illegal as well. I always took that to mean you can't run W cable like you would SE or NM- but OK when used in situations where NM is illegal, like in an aerial drop in a garage.
I contend this is not substituting for the fixed wiring of a structure, as the only thing being substituted is a hard-wire for a plug.
Thanks for the UL quote, that clears up a LOT for me!
Since "do it anyway" is your sentiment here why not just wire up 3 receptacles in a box the same way you were going to wire up 3 strips?
Steve, Forgetting about 400.8(1) for a moment, which section in 400.7 permits what you want to do?
gfretwell, there are legitimate reasons, I assure you. But I can't to get into that detail of operational readiness on an internet forum. Sufficed to say from a financial standpoint, those 3 receptacles would cost us $5000 of your tax dollars to install, while the powerstrip will cost about $20.
Honestly, what's the difference between installing a receptacle and plugging a power strip into it, and hardwiring the power strip? The only difference I see is that you can yank one out of the socket easier. The disconnect switch provides the same level of disconnect/maintenance safety as the plug. The only real issue I see is perception.
I left NEC at work and the online version isn't working for me at the moment, iwire. I will look at 400.7 though! BTW, I talked with suppo again and it looks like we're scaled back enough that I (thankfully) won't need to do this jerry rig. The question still intrigues me, though!
Edit: A case could be made for both 400.7(A)(3) and 400.7(A)(6) to apply and allow this usage of flexible cord. Clearly, power strips (and their flexible cords) are legal in buildings, I don't think there is any dispute there. 400.7(B)/368.56 allows hardwiring under "hard" usage, which is very open-ended. The specific requirements (approved means of attachment, etc.) aren't difficult to meet.
I cannot address many of the code issues but it is possible to purchase a power strip that is suitable for hard wiring. One brand comes in two versions identical except that one has a plug and one is for hard wiring.
Steve are you sure you have the same 2005 NEC as the rest of us?
400.7(A)(3)?
A plug strip is not a portable lamp, sign or appliance. Listings Steve, it's all in the listing.
FWIW Fire inspectors regularly force the removal of 'relocatable power taps' (That is the listing of what we are talking about) When they decide they are being used in place of real wiring.
Say at the the local Mega-marts TV department, the Fire inspector walks in and finds daisy chained relocatable power taps or relocatable power taps supplied by an extension cord or a relocatable power tap fastened in place they are likely to force the removal of them as any of those conditions are listing violations.
One brand comes in two versions identical except that one has a plug and one is for hard wiring.
That is correct, however the hardwired one will not have any rubber cord at all. It will be supplied from a chapter 3 wiring method.
I guess I just can't comprehend the twisted bureacracy that will allow a plug strip to be hard wired in place and wouldn't allow 3 pendants but I lived and worked around the government in DC for 40 years so I am not shocked. My advice is get some good cord grip fittings and go for it. 90-4 as AHJ it and get on with your life.
Eh nuts, listed (3) twice, didn't I? I meant to say "A case could be made for both 400.7(A)(3) as an appliance and 400.7(A)(6) Connection of utilization equipment to permit frequent interchange".
When I say "power strip" I actually mean "surge supressor" which is.... ah... an appliance for stopping surges and not just acting as a relocatable power tap, right??
It's sad when a lawyer would be better able to tell us how we do electrical work than we can. And when we run into technicalities like a power strip vs a surge supressor. There's something wrong with that. Maybe that's what gets me- when I try to apply logic to a legal document and get frustrated when I can't find the code that lets me do what I think I should be able to do something that makes sense not just permitted but quite literally required in far more restrictive applications.
http://youtube.com/watch?v=plAAuk9VwLs What does this youtube have to do with this topic you might ask? Well, try to imagine what might happen to a plug under those conditions... (If you're having trouble imagining, it looks something like this:
http://www.aeronavlabs.com/shockfirst30degreemarlocoil.wmv ) Anyhow, that's why I didn't hesitate to consider just lopping off the plug and hardwiring.
Steve, I can not see how 400.7(A)(6) will help you at all for your proposed installation.
Take a look at 400.7(B) and notice that it requires an attachment plug used with flexible cords used as allowed by 400.7(A)(3), (A)(6) and (A)(8)
And when we run into technicalities like a power strip vs a surge supressor.
In all likelihood if you look at the UL tag on this device you will see "Relocatable Power Tap"
Here is the UL white book info for ‘‘Relocatable Power Tap,’’ ‘‘Power Tap’’ or ‘‘Outlet Strip.’’
RELOCATABLE POWER TAPS (XBYS)
USE AND INSTALLATION
This category covers relocatable power taps rated 250 V ac or less, 20 A or
less. They are intended for indoor use as relocatable multiple outlet extensions
of a single branch circuit to supply laboratory equipment, home workshops,
home movie lighting controls, musical instrumentation, and to provide
outlet receptacles for computers, audio and video equipment, and
other equipment. They consist of one attachment plug and a single length of
flexible cord terminated in a single enclosure in which one or more receptacles
are mounted. They may, in addition, be provided with fuses or other
supplementary overcurrent protection, switches, suppression components
and/or indicator lights in any combination, or connections for cable, communications,
telephone and/or antenna.
Relocatable power taps are intended to be directly connected to a permanently
installed branch circuit receptacle. Relocatable power taps are not
intended to be series connected (daisy chained) to other relocatable power
taps or to extension cords.
Relocatable power taps are not intended for use at construction sites and
similar locations.
Relocatable power taps are not intended to be permanently secured to
building structures, tables, work benches or similar structures, nor are they
intended to be used as a substitute for fixed wiring. The cords of relocatable
power taps are not intended to be routed through walls, windows, ceilings,
floors or similar openings.
Relocatable power taps have not been investigated and are not intended
for use with general patient care areas or critical patient care areas of health
care facilities as defined in Article 517 of ANSI/NFPA 70, ‘‘National Electrical
Code’’ (NEC).
Component power taps may be factory installed on relocatable equipment
intended for use in general patient care areas or critical patient care areas as
defined in the NEC. They are intended to comply with 60601-1, ‘‘Medical
Electrical Equipment, Part 1: General Requirements,’’ and 60601-1-1, ‘‘Safety
Requirements for Medical Electrical Systems.’’ Refer to Medical Equipment
(PIDF).
RELATED PRODUCTS
For relocatable power taps employing cord sets provided with leakage
current detection and interruption, see Cord Sets with Leakage Current
Detection and Interruption (ELGN).
For portable ground-fault circuit interrupters, see Ground-fault Circuit
Interrupters (KCXS).
ADDITIONAL INFORMATION
For additional information, see Electrical Equipment for Use in Ordinary
Locations (AALZ).
REQUIREMENTS
The basic standard used to investigate products in this category is UL
1363, ‘‘Relocatable Power Taps.’’
UL MARK
The Listing Mark of Underwriters Laboratories Inc. on the product is the
only method provided by UL to identify products manufactured under its
Listing and Follow-Up Service. The Listing Mark for these products
includes the UL symbol (as illustrated in the Introduction of this Directory)
together with the word ‘‘LISTED,’’ a control number, and the product name
‘‘Relocatable Power Tap,’’ ‘‘Power Tap’’ or ‘‘Outlet Strip.’’
I find this thread to be very interesting because there are some valid points made by all. iWire's UL references are some I'd not looked at before, about the way UL sees "relocatable power strips".
As for article 400, there is no way that "Uses Permitted" could be all inclusive and I've seen many ways people have safely used these devices. I've also seen them abused by daisy chaining etc.
As for permanently installed, it gets done all the time with UL's blessing by virtue of the fact that most of them come with tabs, ears or slots for mounting. Just to drift for one moment, the code does frown on using cord and cap connection plugged into track lighting. Forgot the article but it's there (I think).
As for permanently installed, it gets done all the time with UL's blessing by virtue of the fact that most of them come with tabs, ears or slots for mounting.
Yes they do often come with mounting means.
But not with ULs blessing as they specifically tell us not to mount them.
Relocatable power taps are not intended to be permanently secured to building structures, tables, work benches or similar structures,
To tell you the truth I mounted a surge suppressor plug strip to a clean room bench just last week. It's odd to me that UL feels it safer to leave it floating than fastened.
I do not see how this can be argued that it is not a substitute for fixed wiring.
It seems to me that this is one of the intents of 400.8.
Its always frustrating when an engineer comes up with a "great" idea on how to jerry-rig something...lol.
I guess I am confused on how a surface mounted 4" square with an offset nipple, device and duplex or double duplex raised mulberry cover would cost $5000.00
From a safety aspect - frayed and overloaded extension cords are a huge hazard no matter how you look it.
Hire a good electrician and get it done right - this sounds like the shoddy work done by "maintenance" in many gov't & commercial buildings
The fact that is "blessed" by an engineer makes no difference to me
In Steve's defense I must point out that you should never under estimate the insanity of federal government rules, particularly in secure sites. As I said upthread, I don't understand the details either but I am not shocked. They do some strange spit.
OK, for the "how-to" part....
The cord connectors with the rubber grommets have over twice the strain relief capability of a simple strap two-screw clamp. They will grip your cord quite well.
I do not know the current available to the disconnect .... I am assuming that the circuit breakers on the power strips will allow you to apply the tap rules.
George,
As for permanently installed, it gets done all the time with UL's blessing by virtue of the fact that most of them come with tabs, ears or slots for mounting.
I haven't seen any with tabs, but the ones with keyhole slots cannot be permanently installed as there is no way to tighten the screw. The plug strip just sets on the screw.
Don
NJ_WVUGrad, it costs the same to contract out a $20 job as it does to contract out a $500,000 job. We get charged a flat fee for "design" and a flat fee for "oversight". So even the smallest job will cost $5000 right off the bat. I guess I could put in a trouble call and complain the outlet is "broken" and needs replaced, which would only cost $500... but paying $500 for a $20 job is still waste. And a lie.
It doesn't actually cost $500 for a hammer- not if you buy a case of 1000 of them at a time. It's when you buy just 1 that it gets outrageous.
I saw an easy solution, one I can safely do myself without ruffling anyone's feathers, and end up with a safe product in the end, even if it doesn't look like the standard way of doing it. I'm well capable of bending EMT and putting boxes precisely where they need to go, but not authorized to do work like that myself- hardwiring a surge supressor, though, that's different!
This disconnect is fed from 3x 15A breakers on a single yoke. It's a fused disconnect switch and missing the fuses (1/phase), so I'd have to install some fuses, but that's not a big deal. (There are 2x 20A fuses in another abanded switch I could use, considering the breaker is already protecting the cable, but I'd rather use 15A) There's a fitting on the switch already, left over from the previous usage, but I didn't look too closely- I highly doubt it's the right kind, but I don't mind swinging by the supply house and spending $2 out of pocket for the right one. So, 15A breaker, 15A fuse and 15A breaker on the surge supressor itself- should be pretty well protected!
I'd want to mount the surge supressor(s) to the wall to make the install look cleaner, but that's just a couple expanding drywall screws.
Responce to Don:
I haven't seen any with tabs, but the ones with keyhole slots cannot be permanently installed as there is no way to tighten the screw. The plug strip just sets on the screw.
Don
I wonder how Bob [iWire] mounted his? But you are correct about the ability to tighten the screws or nail the units to the surface. I personally have bolted them to a surface using bolts and nuts to 1/2" plywood. The feet of the unit were turned in so a self taping screw could not be used. I inspected it myself and gave myself a green sticker
The one I just did had four keyhole slots on the back.
I ran four screws into the bench adjusting them so that I had to bang the plug strip onto them with my fist.
Then I ran a fifth screw in at the end so it could not slip off the key hole slots.
I say it is not 'permanently' mounted, it is just secured for the time being.
It simply plugs directly into a wall receptacle.
Well, try to imagine what might happen to a plug under those conditions... (If you're having trouble imagining, it looks something like this:
http://www.aeronavlabs.com/shockfirst30degreemarlocoil.wmv ) Anyhow, that's why I didn't hesitate to consider just lopping off the plug and hardwiring.
Well one could use twist lock plugs and outlets.
Well one could use twist lock plugs and outlets.
Well, commercial twist-lock plugs unfortunately fail under those conditions, and generally give off too much toxic smoke when they burn. Hell, most commercial products in generally fail under those conditions!
There are mil-spec plugs that are shock rated (and obscenely expensive) but considering all the equipment, including desks and file cabinets, are generally bolted to specially constructed steel foundations that are welded to the structure of the ship, it's not really necessary to use a plug at all for most stuff, and a lot easier and cheaper and takes far less man-hours just to hardwire it- costs about the same to hardwire a plug as it does to install a dedicated 115VAC receptacle.
There are every variety under the sun, but here's a typical MIL-C-26482 plug:
![[Linked Image from schusterusa.com]](http://www.schusterusa.com/images/mini26482.jpg)
Hardwired cord with the NEMA plug chopped off is mostly for commercial stuff adapted for use. Actual mil-spec equipment will never have a cord and plug like that- you don't plug it in, you run a special cable straight from the power panel and plug the cable into the mil-spec equipment. Same with all the data cabling.
What gives you the idea that because you are a PE, you are qualified to perform commercial/government electrical work.
We all work very hard to build a reputation, pay the proper insurances and business permit & license fees and all other associated costs.
I do not agree with the intent of this thread nor the message you are sending to your subordinates or higher-ups at you installation, wherever it mat be
Why have you taken such offense to this thread?
I've worked hard for my licenses and reputation too, and worked extremely hard to get my current position and authority. This is all within my authority and qualifications. I just rarely get my hands dirty because my program's funds aren't unlimited, and I can't afford my own labor rate for work like this. The only reason I'm involved at all is that the suppo asked for my help. I tell ya, after this little escapade, he's going to owe me a new data logging fluke too!
As to what by higher-ups think, I told them straight up what I wanted to do (6 dedicated receptacles, each on 20A circuits, fed via EMT with compression couplings from the distribution panel) and was shot down by my boss, a naval captain, who told me straight up to do it on the cheap. I report to him, it's his call if he wants to make it. I won't condone anything unsafe, but the only thing "unsafe" about this is that it will look cheezy. But it will be hidden anyhow, so that doesn't really matter.
ok so if that is what you want to do then do it. nobody's stopping you, but we're not blessing this installation either as it isn't good practice. to me it sounds as though you just want someone to say "good job!" it should be clear that nobody's going to. it's a shame that it would cost so much to do it right. good luck.
Yeah, I know about your tippy top secret little world where the security concerns border on paranoia. I worked jobs like that in the Pentagon. No inspectors, no permits, nobody to answer to. In spite of this, I felt it was just proper to do the job as close to the code as possible. I was a Federal employee, we did not charge those exorbitant rates to the customers. Now, however, as politics has mandated the contracting of private companies to do the work, we as taxpayers all have to pay the price. If you require top secret, agency approved electricians just so you don't have to have an escort to watch them, you are faced with this dilemma. Just pay the 5,000. It's not your money, and forget about it.
If dealing with Government stupidity bothers you, just quit, like I did, and get a real job.
Let's not get too far off topic here. It's just too easy to do ...
That Steve is an engineer doing electric work - well, that's a whole 'nother issue.
As is the very idea that the US military, with the tens of thousands of trained troops, can't produce a single electrician's mate to do this right ... well, who ever expects sense from the government?
Think of it as "Vigilante action." Steve gets to design, install, inspect, and approve his work. Sort of like being jugge, jury, and prosecutor
Anyway ... I've tested, and examined lots of stuff of this sort in the past; some was even for a testing agency.
By far the main problems discovered had to do with strain relief and abrasion protection. That's why I suggested the heavy duty cord grips.
In a quirk of bureaucratic logic, UL will not list a power strip that can be easily, securely mounted. Their concern has to do with the fear that the circuit would then have too many receptacles (remember that 90 watt per recep thing in the load calcs?) Therefore, the strips can only be 'temporary' ... which in turn suggests NOT being able to bolt them in place.
I didn't say I agreed with this silliness; I'm just reporting it.
A PE is as qualified as an EM in this case. EMs are trained to do wiring on ships as a general rule. They are exempt from the NEC and use very much different systems.
Steve is just humoring us anyway. The Federal Government writes it's own rules, even out in "civvie land". I have worked in lots of government data centers where GSA does the wiring and they pretty much do what they want. They don't get permits and they self inspect. Things do move at "government speed". I had one customer who got frustrated with the plodding pace GSA set and contracted an outside electrician to get his system up. All hell broke loose but he eventually got away with it because it was rental space in a privately owned building so GSA really wasn't supposed to be doing the work in the first place. (although they regularly did).
Heh, I really didn't want to derail the thread with an attack on governmental oversight- I only brought it up to try to preemtively cut off the inevitible "JUST DO IT RIGHT!" comments. The security is always a hinderence and a pain, but it's there for a reason and we have no choice but to accept the cost. The contracting practices border on the absurd sometimes, but it's fundamentally no different than any other large company and designed to stop fraud and favortism.
I've never been active military, always been a civilian. My background is largely shipboard electronics engineering; I worked some shipboard power when it was incidental to my projects, but it was never my bread and butter. My present job is all about shoreside emergency power. NEC is the law, and though I could technically 90.4 whatever I want, that's not the right way to do it- I use strict accordance with NEC wherever possible. When other codes apply, like installs in France, Italy, Germany, Japan, etc- it's strict accordance with whichever code is more stringent. (Usually NEC is the more stringent.)
Think of it as "Vigilante action." Steve gets to design, install, inspect, and approve his work.
Don't forget "answer for" and, unfortunately, "fund"! If, say, the pacific fleet loses satellite communications because I ****ed something up, oh man there would be hell to pay! Redundancy, redundancy, redundancy- practically everything I do is hospital grade.
This particular job is nothing, a side-thought. It's not tactical, it's not terribly important, it's just moving some vending machines. Hell, $5k is nothing, either- it would actually be personally easier for me to submit the job through channels than do it myself, especially considering I'd be funding the material costs from my own pocket! I'm trying to do the right thing here. If I was allowed to, I'd lop the cord off the coke machine and hardwire it directly, but I don't think the coke guys would like that, and the cord's probably wouldn't quite reach. A surge supressor appeared to be an easy, if imperfect, solution.
So, anyhow, I knew hardwiring plugs is safe and common and we did it on ships as a matter of normal practice. I posted the question to this forum because most of us here live and breathe the code and love to play "stump the expert" for a hobby, and figured a few people could probably quote the code permitting or prohibiting off the top of their head! And, armed with that knowledge, I could proceed or come up another plan.
steve, i guess another option you may want to look at is a product made by "wiremold". they make a strip that is intended to be hard wired. it has 1/2" ko's in the back, it comes in different lengths. i think a 5ft strip is about $45 at the big orange..... (fix up your office and sponcer my driver at the same time!)
How about using a Woodhead pendant station?
I like the 34047 style on the bottom right of this page:
http://www.woodhead.com/data/current3054/multitap%20902.pdf or the style on the bottom right of this page:
http://www.woodhead.com/data/current1486/GFCI%20Outlet%20boxes%20902.pdf They are designed to be hardwired.
Not to add to the problems you're dealing with but, if the receptacles are to supply vending machines you need to check section 422.51 of the 2005 NEC. This is a new section and requires ALL vending machines to be GFI protected.
ALAN--
Oh snap, didn't know that! Thanks for bringing it to my attention! Not that they're GFCI protected now, but that's an easy fix.