Compensation Of Earth Electrode Connecting Lead - Fluke 1625 User Manual

1625
Users Manual
Example:
Your clip-on transformer has a transformation ratio of tr = 1000:1. The meas-
urement without clip-on transformer results in a value R
clip-on transformer a value of R
The deviation thus reads (1.175 - 0.983) = + 0.192
0.983 an error evolves as following:
The new transformation ratio to be set calculates:
trnew 1000

Compensation of Earth Electrode Connecting Lead

If the line resistance to the earth electrode can not be ignored, a compensation
of the connecting lead resistance to the earth electrode is possible. Proceed as
described below:
Measuring process:
1625 EARTH / GROUND TESTER
START
TEST
DISPLAY
MENU
AC
Resistance
Earth/Ground Resistance 300 k 300 k
RA R
2
POLE
4
POLE
3
POLE
4 POLE
CHANGE
ITEM 3 POLE
OFF
SELECT
Figure 15. Compensation of Earth Electrode Connecting Lead
1. Turn central rotary switch to position "R
2. Wire instrument according to picture.
44
= 1.175
E
. 1 175
1195
. 0 983
H /C2
S/P2
DC Low Resistance 3k
R
2 POLE
4 POLE
ES/P1
E /C1
Earth
electrode
is measured.
. 0 192
100 %
. 0 983
3pole".
E
= 0.983 . With a
E
and referring to R
19 5 . %
Auxiliary
earth
electrode
edw019.eps
=
E