VR2250
Page 51 of 131
6.5.1. Measurement procedure and results of "2-W"and "3-W" mode
1. Select "
2-W
" or "
3-W
" Earth measurement mode by means of the
F1
key.
2. Connect the Red, Yellow, Green and Black cables to the corresponding input
terminals of the instrument
B1
,
B2
,
B3
,
B4
(see possible connections in the following
pictures).
B2
B3
B4
B1
I1
1
3
N
Connection for 3 point Earth resistance
measurement
B2
B3
B4
B1
I1
1
1
3
3
N
N
Transf
Connection for 2 point Earth Resistance
measurement
B2
B3
B4
B1
I1
1
3
N
Connection for measuring the resistance between an extraneous conductive part and the earth system
3. Press the
START
key. The instrument starts the test.
At the end of the test
the instrument emits a
double sound signal
indicating that the
test is correctly
terminated
and
displays the values
alongside.
EARTH
05.06.01
Earth Resistance value
expressed in
Ω
.
0.77
Ω
Vd= 1V
Test:04
RAVG=0.74
Ω
3-W
Voltage value of electrical
noise
Number of test
Average Value of Earth
Resistance calculated over
the Number of tests
displayed.
"3 Point" Working mode
FUNC CLR
4. The instrument will show automatically the Average value of the Earth resistance
calculated over the tests performed. Press
F2
to RESET this value and the number
of Tests.
This result can be stored pressing the
SAVE
key
twice
(according to paragraph 9.1).
START
STOP
Red
Red
Red
Black
Black
Black
Yellow
Green
Green
Green
Yellow
Yellow