Dc Current Measurements - Unitest CHB 15 Bedienungsanleitung

4.2.1 DC current measurement
1. Turn selector switch (2) to "200 A
Clamp Adapter CHB 10 "200 A".
UNITEST Clamp Adapter CHB 10:
Connect the UNITEST Clamp Adapter CHB 10 to a Multimeter
i.e. a UNITEST Digital Multimeter Order No. 93428 and select
the correct range.
2. Press the button "ZERO", and make sure that "0.000" is dis-
played.
3. Open the clamp, and close it round the conductor. Make sure
that the clamp properly encircles the conductor, and that there is
no air gap between the jaws.
For a positive reading, the current must be flowing in the direction
of the arrow on the clamp.
If the display is not visible during measurement, press the "HOLD"
button (3) to retain the display. The clamp can then be removed
from the conductor and the stored value read. (Clamp Meter CHB
15 and CHB 35 only).
The measurement is not correct, the reading will be zero, because the sum of all
currents is zero (Kirchhoff's 1st. Law). However, with this circuit and a sensitive
clamp meter (for example, the UNITEST Leackage Current Clamp Meter CHB 3,
Order No. 93481), the Leackage current of the machine can be measured.
22
/ 400 A " / UNITEST
correct current
measurement