Benning ST 725 Notice D'emploi page 41

step 1 of 2:
- After a measuring time of 5 seconds or by pressing the key 4 , mains polarity will be reversed
and the contact current will be measured with reversed mains voltage ("L/N" - "N/L"). The
highest measured value of both measurements will be displayed. (step 2 of 2)
step 2 of 2:
- If the contact current is lower than the admissible limiting value, a
the I symbol.
LEAK
- The overall test is considered to be passed, if "PASS" is shown on the display.
As an alternative:
BENNING ST 725 in battery operating mode (without mains supply):
- Similarly, a
leakage current measurement method) is lower than the admissible limiting value.
- The test is considered to be passed, if "PASS" is shown on the display.
See figure 5: Testing of devices of protection class II (shock-proof devices without protec-
tive conductor and with accessible conductive parts) and testing of devices of
protection class III (safety extra-low voltage)
Note on measuring the contact current in mains operating mode:
- During contact current measurement by means of the direct measurement method, no part
of the test object must have a connection to the earth potential. The test object must be
placed onto an insulated surface. Otherwise, leakage currents to earth might influence the
measuring result.
- Alternatively, the measurement of the contact current I
measurement (max. 2 x 5 minutes). Press the key 4 for approx. > 5 seconds to start
permanent measurement. After 5 minutes, the polarity of the mains voltage will be reversed
automatically ("L/N" - "N/L"). By pressing the key 4 earlier, the mains voltage polarity
reversal can be activated manually and by pressing the key 4 again, the measurement can
be stopped.
Please observe that the BENNING ST 725 is not designed for carrying out repeated
permanent measurements at a high load current. If the admissible internal operating
temperature is exceeded, the "StOP" and "hot" symbols will be shown on the display. In this
case, the BENNING ST 725 must be disconnected from the mains and can be used again
after a sufficient cooling phase.
Note on measuring the insulating resistance for test objects of protection class III:
- Due to the preset limiting value of 2 MΩ for test objects of protection class II, for the testing
of test objects of protection class III it has to be observed that measured values between
the limiting values of 2 MΩ (protection class II) and up to 0.25 MΩ (protection class III) are
indicated with a
evaluated by a competent person.
07/ 2018
will be shown next to the I
next to the R
ISO
BENNING ST 725
symbol, if the contact current I
EA
LEAK
symbol. In this case, the measured value has to be
will be shown next to
EA
can be carried out as permanent

(alternative
32