01/ 2011
BENNING 044140/ 044141
11
- Otherwise, the measurement of the protective conductor resistance (R
PE
) will be started with
automatic polarity reversal and the highest measured value of both measurements will be
shown on the display
8
.
- After the R
PE
test has been passed, the test of the protective conductor current I
LEAK
will be
carried out as permanent measurement for max. 30 seconds.
- Make sure that the test sample is protected and switch it on.
- Press the
-key
7
to finish early the measurement.
- If the protective conductor current is lower than the admissible limiting value, a
will be
shown next to the I
LEAK
symbol.
- The overall test is considered to be passed, if "PASS" is shown on the display.
See figure 4:
Testing three-phase test objects under operating conditions (test sample
placed on insulated surface)
Note:
- The protective conductor current measurement will be carried out by means of a current
transformer in the protective conductor of the measuring adapter. The test object must be
placed onto an insulated surface. No part of the test object must have a connection to the
earth potential. Otherwise, leakage currents to earth might influence the measuring result.
- When pressing the
-key
7
without previously connecting the measuring adapter to the
BENNING ST 720, the following warning will be shown on the display:
- For measuring the insulating resistance on three-phase test objects, use the optional pas-
sive measuring adapters (CEE coupling/ shock-proof plug, 044122/ 044123).
9. Maintenance
9.1 Cleaning
Clean the exterior of the housing with a clean dry cloth (exception: special cleaning wipers).
Avoid using solvents and/ or scouring agents for cleaning the measuring adapter.
