HT instruments MACROTEST G3 - Manual (Page 47)

MACROTESTG3 - COMBIG3
EN - 46
6.4.7. Verify of protection against indirect contacts (IT systems)
1. Select the options "IT", “25 or 50V”, “50Hz or 60Hz” and
the reference voltage in the general settings of the
instrument (see § 5.1.3).
Touch the icon. The screen to the side appears on
the display.
Touch the lower icon. The following screen appears on
the display:
2. Move the left slide bar reference by selecting the
icon to execute the measurement.
Move the central slide bar reference by selecting the
"L-PE" option. The right slide bar reference is
automatically set in position
.
Confirm the choice by going back to the initial
measurement screen.
3. If possible, disconnect all loads connected downstream
of the measured point, as the impedance of these users
could distort the test results. Connect the alligator clips
or the remote lead to the electrical mains according to
Fig. 21. Note the presence of the correct voltage values
between L-L and L-PE corresponding to the selections
carried out in the initial phase (see § 5.1.3) and a
possible N-PE voltage due to the IT system as shown
in the screen to the side.
4. Press the GO/STOP key or the START key on the
remote lead. During this whole stage, do not disconnect
the measuring leads of the instrument from the system
under test.
In case of positive result (contact voltage at the point
<50V or <25V), the screen to the side is displayed by
the instrument, which contains the value of the first fault
current measured, expressed in mA (see § 12.8). With
Isc < 30mA the Ut value is not mdisplayed
Press the SAVE button or touch the icon to save
the measurement (see § 7.1).
5. In case of negative result (contact voltage at the point
>50V or >25V), the screen to the side is displayed by
the instrument.
Note the presence of the measurement result of the
contact voltage highlighted in red.
Press the SAVE button or touch the icon to save
the measurement (see § 7.1).