Manual

48 Gossen Metrawatt GmbH
8.14.3 Milliohm Measurement with 200 mA or 20 mA DC [m
KC4 Kelvin clips and KC27 Kelvin probes (available as accesso-
ries) allow for simple, correct connection. The KCV100 accessory
cable reel for 4-wire measurement (100 meters) can be used for
measurements at large objects (see “
Accessories (sensors, plug
inserts, adapters, consumable materials) ” on page 2).
Resistance at the current jacks should amount to <5.
This measuring method is suitable for resistances with induc-
tances of up to 1 H.
➭ Make sure that the device under test is voltage-free (see sec-
tion 8.6.4). Interference voltages distort measurement results!
➭ Set the rotary switch to “m/4”.
➭ Select desired test current Ip set with the  scroll keys.
➭ If applicable, select the desired measuring range using the
Man / Auto key: 30 m, 300 m, 3 (Ip set = +200 mA) or 30 
(Ip set = +20 mA).
➭ Connect the device under test as shown. When using acces-
sories, refer to their respective product documentation.
➭ Activate the measurement by pressing the Start softkey.
➭ If required, activate thermovoltage correction (see description
below).
➭ Press the Stop softkey in order to end the measurement.
Thermovoltage Correction in the 30/300 m Range
➭ Connect the measurement cables and press the TComp soft-
key in order to measure thermovoltage.
Wait until the measured value has settled in. This may take
several seconds, depending upon inductivity. After the mea-
sured value has settled in, press the Save softkey. The TComp
softkey changes color from black to green. All future measure-
ment results will be corrected based upon the previously mea-
sured thermovoltage value.
Thermovoltage can also be measured during a running mea-
surement after pressing the Start softkey.
Use the same procedure as described above.
Measurements at Inductive Devices
Coils, for example in motors, choke ballasts and contactors, are
highly inductive. Changes in current at inductive devices, includ-
ing those caused by switching the milliohmmeter on and off or
changing the measuring range, result in a corresponding voltage
change. These changes may be of significant magnitude, and
may result in arcing under unfavorable conditions. The milliohm-
meter is protected against arcing by means of suitable voltage
arrestors.
8.14.4 Milliohm Measurement with 1 A Pulsating Measuring Cur-
rent (automatic thermovoltage correction at 3 … 300 m)
➭ Make sure that the device under test is voltage-free (see sec-
tion 8.6.4). Interference voltages distort measurement results!
➭ Set the rotary switch to “m/4”.
➭ Connect the device under test as shown.
KC4 Kelvin clips and KC27 Kelvin probes (available as accesso-
ries) allow for simple, correct connection.
Resistance at the current jacks should amount to < 0.5 .
➭ If applicable, select the desired measuring range using the
Man / Auto key: 3m(Ip set = +1 A), (30 mor300 
(Ip set = +1 A)
➭ Connect the device under test as shown.
Thermovoltage is compensated automatically.
➭ Activate the measurement by pressing the Start softkey.
➭ Press the Stop softkey in order to end the measurement.
The 1 A setting for test current can be password protected. If
applicable, you’ll be prompted to enter the valid password (see
section 8.1 on page 24).
Thermovoltage Correction in the 30/300 m Range
➭ First press the Start softkey and then TComp softkey in order to
measure thermovoltage. The TComp softkey changes color
from black to green. Wait until the measured value has settled
in. This may take several seconds, depending upon inductiv-
ity. Future measurement results will be corrected based on the
previously measured thermovoltage value.