Underwriters
Laboratories
Inc.®
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Are AFCIs required to undergo monthly testing like
GFCIs?
Some GFCIs are “switch
rated.” Are all GFCIs with
a deadfront “switch rated”?
Similar to GFCIs, UL 1699,
the Standard for Arc-Fault
Circuit Interrupters does
require monthly testing. This requirement is communicated in the
installation instructions. The installation instructions are also standardized to reduce the likelihood of
miswiring.
Information and current Listings
for AFCIs can be found under the
category of Arc-Fault Circuit Interrupters, Branch/Feeder Type (AVZQ)
and Arc-Fault Circuit Interrupters,
Outlet Branch Circuit Type (AWBZ)
on the UL Certification Database at
www.ul.com.
The “TEST” and “RESET”
buttons on a GFCI are only
intended to check the
proper functioning of the GFCI.
They are not intended as “ON”
“OFF” controls of motors or other
loads. Only GFCIs that are specifically marked “ON”/“OFF” have been
“switch rated.” Products with “ON”
and “OFF” markings have been additionally Listed as “Miscellaneous
Motor Controllers” (NMFT).
Do GFCI receptacles carry
a horsepower rating?
GFCI receptacles do have
a horsepower rating; the
horsepower rating of the
receptacle would correspond to the
standard horsepower ratings found
in the Guide Information for the category, Receptacles for Attachment
Plugs and Plugs (RTRT). For a 125V,
15A receptacle the horsepower rating is ½ horsepower and for 125V,
20A receptacle the horsepower rating is 1 horsepower.
GFCIs are Listed under the category Ground-Fault Circuit Interrupters (KCXS) and are not intended to act as “ON/OFF” controls
for motors or other loads, unless the
buttons are specifically marked
“ON”/“OFF.”
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IAEI NEWS
Since it is required as part
of the Listing to use a
bubble cover with GFCIs in
wet locations, shouldn’t the NEC be
revised to indicate this?
orientations or are markings indicating the proper orientation required?
Damp location receptacle
covers can be mounted in
any position as long as the
cover will close when the receptacle
is not in use. However, wet location receptacle covers should only
be mounted in the positions illustrated in the installation instructions
provided with the Listed product.
Are antioxidant compounds required on all aluminum wire connectors?
When used in wet locations, UL Listed GFCI receptacles are required to
have a weatherproof (“bubble”)
cover. This is specified in the “standardized” installation instructions
provided with all UL Listed GFCI receptacles. These installation instructions are outlined in UL 943, the
Standard for Ground Fault Circuit
Interrupters.
In regard to revising the NEC, in
the proposed 2002 NEC, new Article
406, Section 406.8(B)(1) will require a weatherproof cover for 15
and 20A outdoor receptacles in wet
locations.
Some UL Listed aluminum
wire connectors are prefilled
with the UL Listed antioxidant compounds at the factory. For
the non-prefilled connectors, the
antioxidant compounds should be
used if recommended by the manufacturer. However, the non-prefilled
connectors meet the requirements in
UL 486B, the Standard for Wire Connectors for Use with Aluminum
Conductors, without the compound.
Wire Connectors for use with aluminum conductors are Listed under
the category Wire Connectors and
Soldering Lugs (ZMVV). Antioxidant
compounds are Listed under the
category Conductor Termination
Compound (DVYW). Compounds
under this category have been evaluated and shown not to cause adverse effects on the conductor/conductor combination.
Does UL test wet location
and damp location receptacle covers in all possible
What metals are permitted
to be used for ground
clamps?
Underwriters
Laboratories
Inc.®
Ground Clamps are Listed
under the category Grounding and Bonding Equipment (KDER).
A grounding or bonding device is
required to be constructed of a metal
or metals that, when the device is
installed under conditions of actual
service and exposed to moisture, it
is not likely to be adversely affected
by electrolysis. A grounding or bonding device marked as acceptable for
burial in earth or embedment in concrete is required to be constructed
of copper or a copper alloy contain-
TESTING LABORATORIES FORUM
ing not less than 80 percent copper,
or stainless steel.
The Standard for Grounding and
Bonding Equipment, UL 467, does
allow for other materials for a device
intended for burial in earth or embedment in concrete if it has been investigated and found to be acceptable for
the application. Among the factors
that are taken into consideration
when judging the acceptability of such
a material are the change of resistance
across the bonding-grounding
joint, and the amount and degree of
corrosion. Aluminum or aluminum
compound is not permitted for
“direct burial” applications.
The special UL meetings for government inspectors provide us an excellent opportunity to ask questions of UL engineers and to clarify UL requirements. The “UL Question
Corner” answers questions of general interest that are sent in
from authorized governmental inspectors and we believe will
have interest for many inspectors.
Please send us questions you may have that are of
general interest, and we will have UL engineers answer them
in a future issue. If space does not permit answering all
questions received, we’ll see that you get an answer by letter.
Send your questions to:
UL Question Corner - IAEI News
PO Box 830848
Richardson, TX 75083-0848
SEPTEMBER/OCTOBER 2001
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