Amprobe DMIII-Multitest Power-Quality-Recorder - Manual (Page 32)

AMPROBE
DMIII MULTITEST
EN-30
6.4. GROUND TEST: SOIL RESISTANCE AND RESISTIVITY MEASUREMENTS
Turn the rotary knob to the GROUND TEST position.
The F1 key permits to select one of the following measuring modes (which
can be shown cyclically when pressing the key):
 Mode "2-W" (the instrument measures the resistance between 2 points).
 Mode "3-W" (the instrument measures the resistance using two auxiliary
earth rods).
 Mode " 
" (the instrument measures the ground resistivity).
ATTENTION
Never disconnect the test leads from the circuit under test when the message
"MEASURING" is displayed
6.4.1. Measurement procedure and results of "2-W"and "3-W" mode
1. Select "2-W" or "3-W" Ground measurement mode by means of the F1 key.
2. Connect the Black, Red, Blue and Yellow cables to the corresponding input terminals
of the instrument T1, T2, T3, T4 (see possible connections in the following pictures).
1
3
N
T1 T2 T3 T4
I1 I2 I3
(V1) (V2) (V3) ( COM)
Connection for 3 point Earth resistance
measurement
1 1
3 3
N N
Transf
T1 T2 T3 T4
I1 I2 I3
(V1) (V2) (V3) (COM)
Connection for 2 point Earth Resistance
measurement
1
3
N
T1 T2 T3 T4
I1 I2 I3
(V1) (V2) (V3) (COM)
Connection for measuring the resistance between an extraneous conductive part and the earth system
3. Press the START key. The instrument starts the test. START
STOP