User manual

GMC-I Messtechnik GmbH 17
1)
Leakage current measurement must be performed if the applicable limit value is fallen short of.
Note: „OL“ means measured value > 20 MΩ.
Attention!
!
If a value of 0.3 MΩ is fallen short of for safety class I devices with heating elements,
equivalent leakage current measurement must be performed and passed in accor-
dance with chapter 5.6.1, page 19.
Each exposed conductive part must be contacted with the test probe connected to
the jack (10), and insulation resistance must be measured for safety class II and III
devices, and battery powered devices.
No insulation resistance measurement is required for safety class III devices, or for
battery powered devices which fulfill both of the following conditions:
– Nominal power ≤ 20 VA
– Nominal voltage ≤ 42 V.
Batteries must be disconnected during the performance of measurements at battery
powered devices.
Discharge of the DUT for the avoidance of electrical shocks
➭ After insulation resistance measurement on capacitive objects:
Set the measuring function selector switch one position further to the left to switch posi-
tion „I
EA
20 mA“, in accordance with the standard-compliant test sequence. The DUT is
automatically discharged. Contact with the device under test must be maintained to this
end.
5.5 Measurement of protective conductor current
Protective conductor current must be measured
in instruments featuring a protective conductor/
earth-contact plug.
The following methods may be used for mea-
surement:
• Measuring Equivalent Leakage Current
• Measuring Residual Current
Frequency response is taken into consideration
in accordance with the graph to the right during
leakage current measurement.
Note!
The following schematic diagrams refer to DUTs with a mains plug. See also
chapter 4.4
Device Type Limit Value
Minimum Display Value
Safety class I devices 1 MΩ 1.15 MΩ
Safety class I devices with heating elements 0.3 MΩ
1)
0.38 MΩ
Safety class II devices 2.0 MΩ 2.25 MΩ
Safety class III devices and battery powered devices 1000 Ω/V or 250 kΩ
10 10
2
10
3
10
4
10
5
10
6
+20
0
–20
–40
–60
Frequency (f) in Hz
Relative Quantity (dB): 20 log
U(f)
U(f=10)