- 10 -
instrument interface or poor contact; to avoid the error caused by the user
to replace or lengthen the test line, the line resistance check function is
specially designed to measure the low-value resistance more accurately.
After connecting the test line and the meter, short the other end of all
the test lines. As shown in the figure below, press the function button R
to switch to the corresponding ground resistance measurement position. Press
“
”
key to start calibration, LED indicator flashes during calibration,
LCD countdown display, LCD display after calibration.
Shutdown does not save the verification line resistance. The next time
it is turned on, it needs to be recalibrated.
5
．
Four-wire precision test grounding resistance
When testing the grounding resistance, first confirm the
grounding voltage of the grounding wire, that is, the voltages
of H and E or S and ES must be less than 20V. If the grounding
voltage is above 5V, the meter displays the NOISE symbol, then,
the measurement value of the grounding resistance may be
inaccurate. At this time, the measured grounding device is first
de-energized so that the grounding voltage is lowered and then
the grounding resistance test is performed.
Four-wire test: The four-wire test eliminates the influence of the
contact resistance (usually dirt or rust) on the measured grounding body,
auxiliary grounding bar, test clip, and the input interface of the instrument
to the measurement, can eliminate the impact of wire resistance on the
measurement, better than the three-wire test.
See the following figure: Beginning with the measured object, generally
Summary of Contents for ES3001
Page 1: ......
