2.2
Starting up the megohmmeter
The switch is set to
. All segments of the display unit light for a
few seconds (see Figure 2, §1.1), the screen corresponding to the
chosen function then appears. The megohmmeter is then ready to
make measurements.
2.3
Switching the megohmmeter off
The megohmmeter can be switched off manually, by setting the
switch back to
. It is switched off automatically after 10 minutes
of non-use. At the 9th minute, 5 beeps indicate that the
megohmmeter will soon be switched off. To reactivate the
instrument, press any key on the keypad.
A long press on the HOLD key at start-up de-activates the automatic
switching off of the device.
2.4
The prop
The prop is used to hang the megohmmeter from a support, or to
the place it in an inclined position on a support.
3. FUNCTIONS
3.1
Functions of the switch
To access the functions of the switch, set the switch to 1000V,
500V, 250V,
, VAC, VDC,
3.1.1 Insulation measurement
Description of the measurement principle:
The device generates a DC test voltage greater than the
chosen nominal voltage Un between the COM and V-
terminals. This voltage depends on the resistance to be
measured. It is greater than or equal to Un when R is
greater than or equal to Rn = Un/1mA, less than Un
otherwise. The device measures the voltage and the
current across the two terminals and from them deduces
the value R = V/I.
The instrument measures:
the insulation resistance, at 3 different voltages (1000V, 500V, or
250V);
To measure an insulation resistance, proceed as follows:
1.
Set the switch to 1000V, 500V or 250V.
2.
Connect the black lead to the COM terminal and the red lead to "V- ";
3.
Place the contact tips on the terminals of the circuit to be
measured;
or k .
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