KYORITSU 3023 - Manual (Page 15)

(6) Set the Range selector switch to the OFF position, and disconnect
the probes from the instrument.
DANGER
¡ Never touch the circuit under test immediately after testing.
Capacitance stored in the circuit may cause electric shock.
Leave the test leads connected to the circuit until the LIVE LED
and LIVE circuit warning stop flickering.
6-3 Continuous measurement
For continuous measurement, a lock-down feature is incorporated on
the Test button. Pressing and turning clockwise locks the button in
the operating position, the button is released by turning it
counterclockwise.
DANGER
¡While the Test button is locked down, a high voltage is present at
the tip of a probe. Attention should be paid to avoid possible shock
hazard.
6-4 Output voltage characteristics
This instrument conforms to IEC61557. This standard defines that the
nominal current shall be at least 1mA, and the lower limit of the
insulation resistance maintaining the nominal voltage at the
measurement terminal. (See the graph below.)
This value is calculated by dividing the nominal voltage by nominal
current. i.e., in case that the nominal voltage is 500V, the lower limit
of the insulation resistance is found as follows.
Divide 500V by 1mA equals 0.5MΩ.
That is, insulation resistance of 0.5MΩ or more is required to provide
the nominal voltage to the instrument.
― 13 ―
Nominal voltage
1MΩ
1000V
0.5MΩ
500V
0.25MΩ
250V
0.125MΩ
125V
0.100MΩ
100V
50kΩ
50V
Lower limit of ins-
ulation resistance
to supply nominal
current 1mA