These warnings only end if the voltage falls below 25 V
(disconnection of the leads or removal of the voltage) or if the
yellow key is released or, naturally, if you turn off the instrument
by returning the switch to the OFF position.
The instrument indicates if the value measured is outside
its measurement range. Above 600 V, the digital display
indicates OL.
3.1.2 Insulation Measurement
If there is not a dangerous voltage (see § 3.1.1.), the user can
then measure the insulation by pressing the yellow key. The
high voltage is then generated between the terminals (marked
+ and -). The value of the measurement is shown on the
logarithmic scale of the bargraph and on the digital display, with
the corresponding MΩ or GΩ symbol. As soon as the yellow
key is released, the instrument returns to voltage measurement
mode.
If the voltage generated may be dangerous, the
is displayed.
The instrument indicates if the value measured is outside
its measurement range. If the insulation resistance is greater
than 400 MΩ (1039), 2 or 20 GΩ (1035), the OL symbol
is displayed on the digital measurement display. When the
measurement is greater than 1.1 GΩ (even on the 1039),
the
symbol lights up on the right-hand side of the bargraph.
Similarly, the digital measurement display indicates " - - - " if the
insulation resistance is less than:
1039
10 kΩ at 50 V or 20 kΩ at 100 V
1035
10 kΩ at 50 V, or 20 kΩ at 100 V, or 50 kΩ at 250 V, or 100 kΩ at
500 V
When the measurement is less than 7 kΩ , only the
lights up on the left-hand side of the bargraph.
To measure high insulation values, you are advised to use the
"G" guard terminal to remove the influence of superficial leak
currents and "hand capacitance" (see § 10.2.2).
3.2
Resistance
Resistance measurement corresponds to the 40 kΩ position of the
switch on the 1039 and the 400 kΩ position on the 1035.
The measurement is indicated on the digital measurement
display, accompanied by the Ω or kΩ symbol if necessary.
The instrument indicates if the value measured is outside
its measurement range. If the resistance is greater than 40 kΩ
or 400 kΩ , depending on the instrument, the OL symbol is
displayed on the digital measurement display.
A programmed threshold may trigger an alarm (see § 4.5).
30
symbol
symbol