Application Note

6 Fluke Corporation Clamp Meter ABCs
Glossary
Accuracy. How close the
displayed measurement is to
the actual value of the signal
being measured. Expressed as a
percentage of reading or a as a
percentage of full scale.
Analog Meter. An instrument
that uses a needle movement to
display the value of a measured
signal. The user judges the read-
ing based in the position of the
needle on a scale.
Annuciator. A symbol or icon that
identifies a selected range or a
function
Average Responding Meter.
A meter that accurately measures
sinusoidal waveforms, while
measuring non-sinusoidal wave-
forms with less accuracy.
Non-Sinudoidal Waveform.
A distorted waveform such as
a pulse train, square waves,
triangular waves, sawtooth waves
and spikes.
Resolution. The degree to which
small changes in a measurement
can be displayed.
RMS. The equivalent dc value of
an ac waveform.
Sinusoidal Waveform. A pure
sine wave without distortion.
True-rms Meter. A meter that
can accurately measure both
sinusoidal and non-sinusoidal
waveforms.
Independent testing is the
key to safety compliance
How can you tell if you’re getting a genuine
CAT III or CAT II meter? Unfortunately it’s not
always that easy. It is possible for a manu-
facturer to self-certify its meters as CAT II or
CAT III without any independent verification.
Beware of wording such as “Designed to meet
specification...” Designer’s plans are never a
substitute for an actual independent test. The
IEC (International Electrotechnical Commis-
sion) develops and proposes standards, but it
is not responsible for enforcing the standards.
Look for the symbol and listing number of
an independent testing lab such as UL, CSA,
TÜV or other recognized approval agency.
That symbol can only be used if the product
successfully completed testing to the agency’s
standard, which is based on national/inter-
national standards. UL 3111, for example,
is based on IEC 1010-1 2nd Edition. In an
imperfect world, that is the closest you can
come to ensuring that the multimeter you
choose was actually tested for safety.
Meter ratings and capabilities vary
by manufacturer. Before working with
a new meter, be sure to familiarize
yourself with all operating and safety
procedures for that meter contained in
the users manual.
LISTED

950 Z
R
Fluke Corporation
PO Box 9090, Everett, WA 98206 U.S.A.
Fluke Europe B.V.
PO Box 1186, 5602 BD
Eindhoven, The Netherlands
For more information call:
In the U.S.A. [phone] or
Fax [phone]
In Europe/M-East/Africa [phone] or
Fax [phone]
In Canada (800)-36-FLUKE or
Fax [phone]
From other countries [phone] or
Fax [phone]
Web access: http://www.fluke.com
©2005-2010 Fluke Corporation.
Specifications subject to change without notice.
Printed in U.S.A. 10/2010 2562791C A-EN-N
Modification of this document is not permitted
without written permission from Fluke Corporation.
Fluke. Keeping your world
up and running.
®
NOTE: The N number is different for each company i.e. Agilent, Fluke etc.
N10149
Preferred size Minimum size
Agilent
N10149
N10140
Preferred size Minimum size
Fluke
N10140