Datasheet

WZ11 and WZ12
Clip-On Transformers and Sensors for
Alternating Current
3-349-017-03
6/7.14
GMC-I Messtechnik GmbH
WZ11
WZ12
Description
The basic model WZ12A includes a soft-iron core and is used for
general current measurement starting at 15 A. It demonstrates
traditional, cost-effective current transformer design with a
transformation ratio of 1000:1.
All other WZ12 series clip-on current sensors are equipped
with a top quality metal core which reduces eddy-current loss,
and allows for accurate measuring results even with low primary
current.
Damping diodes integrated into the measurement output of the
current transformers (with current output) protect the secondary
side against overvoltages which occur if the measuring circuit is
interrupted, or if the measuring instrument has not been
connected.
This function is performed by internal load resistors for the current
sensor models (with voltage output).
Thanks to their compact design, these current clips easily fit into
any service case or accessory compartment. Depending on type,
they are suitable for the measurement of motor current, for
measurements at distributor terminals (WZ12A) or for the mea-
surement of minimal to intermediate current (WZ12B) at machin-
ery and current consumption at electronic devices, or for the
measurement of residual current as of 1 mA (WZ12C, Clip 0100S
with selectable measuring ranges), right on up to measurements
in systems with up to 240 A.
Rugged mechanical construction and all requirements set forth by
the latest international safety standards are taken into consider-
ation in the design concept of the clip-on current transformers.
WZ11 current clips are physically somewhat larger than WZ12
series devices, but they offer a larger spectrum of current
measuring ranges and a higher voltage category.
Applicable Regulations and Standards
Characteristic Values
* Max. 10 min followed by 30 min pause
IEC 61010-1/EN 61010-1/
VDE 0411-1
Safety requirements for electrical equipment
for measurement, control and laboratory use
EN 60529
VDE 0470, Part 1
Test instruments and test procedures,
protection provided by enclosures (IP code)
DIN EN 61326
VDE 0843 Part 20
Electrical equipment for measurement, control and
laboratory use – EMC requirements
Type WZ11A WZ11B
Measuring Range 1 200 A~ 0.5  20 A~ 5  200 A~
Allowable Overload 240 A~ * 240 A~ *
Frequency Range (Hz) 48
65400 30 48 65 500
Output Load R
b
<1 >1M
Intrinsic Error
 (% reading + 0.5 A)
0.510 A: 3%
0.1 A20 A:
1%+50 mV
0.510 A: 3%
1040 A: 2.5% 1040 A: 2.5%
40100 A: 2% — 40100 A: 2%
100240 A: 1% — 100240 A: 1%
Phase Angle Error
under Reference
Conditions
0.510 A: — 0.510 A: — 0.510 A: —
1040 A: 5° 1020 A: 5° 1040 A: 5°
40100 A: 3° — 40100 A: 3°
100240 A: 2.5° — 100240 A: 2.5°
Transformation Ratio 1000:1 1 mV/mA 1 mV/A
Features
• Pointed clip jaws for easier access
with dense cable arrays
• Safety in accordance with IEC 61010-1 and IEC 61010-2-032
• Minimal transformation error
• Suitable for use with power meters
thanks to minimal phase angle error (exception: WZ12A)
• Compact, handy design
• Permanently connected safety cables
• Current or voltage output
Applications
WZ11 and WZ12 clip-on current transformers and sensors have
been developed as accessories for multimeters, power meters,
power analyzers, recorders and data loggers. They are used for
electrically isolated measurement of alternating current within a
broad range, without interrupting the current conducting cable.