MULTIOUTLET ASSEMBLIES LISTING REQUIREMENTS
Can a 15-ampere multioutlet assembly (plugmold) be
installed on a 20-ampere circuit?
15-ampere multioutlet assemblies (UL-PVGT) are intended
for use only on 15-ampere branch circuits.
Tom Lichtenstein, Ext. 42160
Staff Engineer, Regulatory Services Underwriters Laboratories Inc.
Mike Holtís Comments:
I personally spoke to Tom about this issue and I was shocked at his answer. I thought a 15-ampere multioutlet
assembly would be permitted on a 20-ampere circuit because Table 210-21(b)(3) in the NEC permits 15-ampere
receptacles (if more than one) to be on a 20-ampere circuit. Tomís response was that if the multioutlet
assembly used a No. 12 wire instead of a No. 14 wire, then the assembly should have a current rating
Now I am curious.† What size conductors are typically used in multioutlet assemblies? If any of my
e-buddies have a multioutlet assembly lying around, would you let me know?† What size wire is used
between the 15-ampere receptacles?
While weíre at it, do they sell (make) listed multioutlet assemblies with 20-ampere receptacles? If
they do, what size conductor is used between the 20-ampere receptacles? Are there any markings on
multioutlet assemblies as to the maximum circuit the assembly can be installed on?
Response No. 1:
I just heard from the Wiremold rep. He confirmed what I said in my E-mail to you the other day. Wiremold
is wired with 12-AWG conductors and is available with 15 or 20-ampere receptacles. So, it would seem
to me that even if you used the Wiremold with 15-ampere receptacles, it would be permitted to connect
that to a 20-ampere branch circuit. I suppose it is possible that another manufacturer might use 14-AWG
for their 15-ampere plugmold, and 12-AWG for their 20-ampere plugmold.
Now I have a simple question for you.† A contractor asked, "How do I install a GEC for a large
service on an industrial building? The service in the rear of the building is about 400 feet from
the front of the building where the main water service comes into the building. Do I have to run the
GEC all the way to make the connection to the first five feet of the water main? The building is of
Must the GEC be run to the first five feet, or is there some other way to do it? Four hundred feet
is an awful long way to run the GEC. What about voltage drop on the GEC for such a long run? Thanks
for your ideas.
Ray C. Mullin, RCMullin@aol.com
Response No. 2:
RE: "plugmold" - I looked at a section I had on hand. It is 15-amp rcptl with No.12
wire. From the Wiremold Catalog - 2000 Plugmold: The harness shall consist of 15A, 125V spec grade
receptacles, factory wired with No.12-AWG-typeTHHN conductors to enable use on 20A branch circuits.
This is from a 1992 catalog. We don't use Wiremold much anymore.
Response No. 3:
The 15-amp multioutlet assembly comes with a 14-AWG
wire. I haven't seen any assembly with a 12-AWG. I guess you can special order them but itís not a
Clifford Rambaran, TSgt, firstname.lastname@example.org
Response No. 4:
We have No. 12 wire in our assemblies and the catalog
lists only No. 12, but only 15A rcpt in a multi of length No. 20A.
Response No. 5:
I opened a couple of old plugmold assemblies a few
months ago but I donít know how old they were. We replaced them because of damage done to them. I
was quite surprised to find No. 16 between the outlets.
Response No. 6:
The plugmold we've used has 12 solid between the
Response No. 7:
I never looked for any markings or ratings on a multioutlet
assembly/plugmold. The ones I installed were on 20A circuits. The receptacles were 20A and the wire
running through the assembly was always 20A. However, I have always felt the individual connections
to the receptacles were a little questionable. The wires are "stabbed" by sharp points as
they pass the receptacles. If each receptacle is rated 20A, how can this kind of connection be good
enough? I thought "backstab" residential receptacles were bad enough. This seems worse!
Response No. 8:
I am responding to your inquiry regarding multioutlet
assemblies listing requirements. I have the following product, which has been lying around in my shop
for several years because the toggle switch failed.
1) The nameplate information is as follows:
MULTIPLE OUTLET POWER STRIP 125 VAC- 15A -60 Hz 1875 watts MAXIMUM #853- 6 OUTLETS CIRCUIT BREAKER
PROTECTION - CAUTION: USE ONLY INDOORS- DRY LOCATIONS -UL LISTED 2781 TEMPORARY POWER TAP, CONSUMER
PRODUCTS DIVISON, SQUARE D COMPANY, PUSH TO RESET ---->
2) Personal Observations:
The three duplex receptacles are rated at 15-amperes- The internal wiring is No.14. The circuit breaker
has the following label- ELECTRICAL PRODUCTS INC., JACKSON, MICH 1600-117-150, 125/250 VAC 2483 -
The reverse UR symbol and the CSA symbol. No specific evidence of a current rating. This device appeared
to be well-made using quality components.
I hope that this one data point together with others that you gather will be helpful. I am looking
forward to the conclusions reached after you collect all of the responses.
Dr. Dale Rummer, P.E.email@example.com
Response No. 9:
On somewhat of a related UL note... A few years back, I wrote to UL asking them to confirm my suspicion
that a UL listing does not necessarily mean compliance with the NEC. They confirmed it. Here's the
My circular saw has a nameplate of 115 volts and 13-amps. The saw has a NEMA 15-amp plug and is UL
listed. The NEC states that any cord-connected load shall not exceed 80% of the branch circuit rating
(see postscript).† Eighty percent of 15-amps is 12-amps. Therefore, connecting the saw to a 15-amp
circuit seems to be a code violation.
I received a letter back from UL laboratories indicating that compliance with the NEC was not a prerequisite
to receiving a listing.† Looking at it from the other direction, the NEC takes a 'hands off' approach
to anything that is listed. Therefore, it can be interpreted that the NEC only applies to installations,
not listed assemblies. Now, if one were to build a multioutlet assembly using parts from a hardware
store, code compliance becomes an issue because this is most certainly not a listed assembly.
Table 210-21(b)(2) shows this. 210-23(a) specifically states "The rating of any one cord and plug
connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating."
Response No. 10:
Just a few comments on 15-amp multioutlet assemblies, which I take to mean plugmold and similar, such
as made by Wiremold. I have frequent occasions to specify data and wire raceways and plugmold for
computer installations. Often, for capacity reasons, I need two 20-amp circuits in the raceway or
plugmold and Iím annoyed that Wiremold does not offer plugmold hardware in full 20-amp capacity wire
and does not offer the double neutral that is needed for harmonic currents in polyphase installations.†
I spoke to my Wiremold sales rep several times on the matter and he said he would take it up with
the factory staff to add the double neutral to their product line. The result has been the same sound
as one hand clapping. I no longer use their plugmold and now use only dual-channel raceway, such as
Panduit or Wiremold for harmonic producing loads.
I got the same lack of response on the issue of the
15-amp wire in plugmold when I pointed out numerous times that commercial grade wiring is almost always
full 20-amp minimum.
I hope others have additional comments for your subscribers.
Response No. 11:
†I have a 20-ampere assembly that has No. 12 wire.
Daniel Vance, firstname.lastname@example.org
Response No. 12:
According to the specification in the Wiremold catalog, plugmold 2200 comes factory-wired
with No. 12 THHN conductors "to enable use on 20A branch-circuits."
P. J. McGuire, email@example.com
Response No. 13:
I have only seen No. 12 Cu [THW for older,
THHN for newer] conductors on "plugmold" strips, which have 15-amp receptacles. This is
true of the strips with receptacles at 6-inch centers and 12-inch centers. I don't recall seeing any
20-amp receptacles, so I'll ask around and check out plugmold at our wholesale house.
Scott E. Thompson, adst@SoCA.com
Response No. 14:
At our facility, we have primarily Wiremold products
installed varying in age from 15 years to new. In all I have encountered, 12-gage wire is used. We
have both 15 and 20-amp receptacles in pre-fab and onsite fabrications of surface raceways. The Wiremold
catalog I have (1991) does note the applicable section of the NEC for derating ampacity of conductors
when more than three conductors are contained in a raceway (Tables 310-16 through 310-19). One note
is the derating factors do not apply to conductors installed in surface raceways when all conditions
of Article 352-4 are met. I mention this for multicircuit plugmold applications.
Hope this helps.
Response No. 15:
I am looking at a Wiremold catalog. They show 15-amp,
120-volt, (NEMA 15R) receptacles for one series using 12-AWG THHN conductors. They show 20-amp, 120-volt,
(NEMA 20R) receptacles for another series using 12-AWG THHN conductors. I cannot find 14-AWG conductors
in their plugmold series. I put in a call for the Wiremold rep. He is on vacation, so I will try to
reach him again next week.
Ray C. Mullin
Response No. 16:
I found a plugmold multioutlet assembly manufactured by Brooks, model A-506, with 10-15-amp spec grade
receptacles. Conductors inside are No. 12 THHN/THWN. Sticker on the back says, "to be used with
not more than two additional conductors No. 14 or No. 12-AWG. Types TW, THHN or THWN conductors 15A,
125V". I thought they could only be used on 15-amp ckt. An additional question I have is do they
have to be hard wired to circuit or can you put a cord on them with a plug?
Steve Spooner, firstname.lastname@example.org
Response No. 17:
You aroused my curiosity. I went to our warehouse
and found several pieces of multioutlet assembly wireways of different brands. I didn't see any 20-amp
rated receptacles though but all the different pieces lying around had No. 12 wire installed in them.
Fred Madden, email@example.com
Response No. 18:
Page 735 of the current W.W GRAINGER catalog shows
both 15 and 20-amp versions spec'ed with 12- ga and 15-amp NEMA 5-15 receptacles.