Megger LCB2000/2 Guide De L'utilisateur page 25

Operation - RCD Testing
Setting A: The contact or fault voltage is displayed with
the Loop or earth resistance and trip time available by
pressing the ENTER key.
Setting b: The trip time is displayed with the
contact/fault voltage and Loop/earth resistance
available by pressing the ENTER key.
150mA 40ms test
When an RCD is fitted for personal protection, a test
current of 150mA must cause the RCD to trip in less
than 40ms.
1. Select 150mA 40ms on the rotary switch.
2. Connect to the supply as detailed below.
3. Select and set the Trip Test to 0° or 180° using the
TEST TYPE key.
4. Press the TEST key.
If the RCD trips within 40ms, the trip time is displayed.
Ramp Test (measuring the trip current)
The trip current is measured by applying a test current
of half the rated trip current and increasing this every
200 ms. When the supply is cut, the current flowing is
recorded and displayed.
A low trip current could be due to an overly sensitive
RCD, or to leakage currents in the supply.
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To determine the trip current of an RCD.
1. Select an appropriate RCD rated current on the
rotary switch.
2. Connect to the supply as detailed on the next page.
3. Select the Ramp test using the TEST TYPE key.
4. Select the RCD type using the TYPE key.
5. Press and hold the Test button.
If the RCD trips, the first displayed result depends upon
the Setting selected.
RCD Rating Current Range
10mA 5..15mA
30mA 15..50mA
100mA 50..150mA
300mA 150..300mA
500mA 250..500mA
1000mA 500..1040mA
Step Value
1mA
1mA
2mA
6mA
10mA
52mA