Megger LRCD200 series, Руководство пользователя

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the RCD should NOT trip.
7. Refer to the application note on Touch Voltage at the end of this section.
NOTE:
If the RCD should trip while performing a 1/2I test the error
message ‘
trP
’ will be displayed instead of the time display.
1x
I
RCD trip time measurement
To test the [1xI] trip time of the installed RCD:
1. Repeat the previous test for 1/2I, but with the bottom range knob set to I.
The RCD trip indicator will display an open symbol .
2. The instrument should display the RCD trip time in milliseconds.
If the display shows >300 ms the RCD has failed to trip in the appropriate
time. Check your test lead connections to the RCD and repeat the test.
If the RCD still fails to trip, suspect a faulty RCD.
Note: See also 0°/180° testing below.
The RCD test may abort with “>25 V” or “>50 V” depending on touch
voltage setting message if the loop resistance is so high that the test cannot
proceed.
5x
II
RCD trip time measurement
1. Repeat the previous test for 1/2I, but with the bottom range knob set to
5xI. The RCD trip indicator should display an open symbol .
2. The instrument should display the RCD trip time in milliseconds.
If the display shows >40 ms the RCD has failed to trip in the appropriate
time. Check your test lead connections to the RCD and repeat the test.
If the RCD still fails to trip, suspect a faulty RCD.
15
RCD type selection
To select the RCD type to be tested:
1. Set the top RCD selection knob (top knob) to the desired RCD current
range.
2. Set the RCD test knob (lower knob) to 1/2I, I or 5I as required.
3. Press the [TYPE] button to select the type of RCD under test:
Options are:
AC Standard (displays ‘AC’) (Default)
AC Selective (displays ‘AC.S’)
DC Sensitive (displays ‘dc’)
DC Selective (displays ‘dc.S’)
1/2
II
RCD (Non-tripping) measurement (LRCD210 and 220)
To test the tripping time of the installed RCD under test:
Range selection:
1. Connect the mains plug or test lead 3-wire Red/Green/Black test lead to
the instrument.
2. Plug in the mains plug test lead to the wall outlet, or the 3 wire test lead
across the RCD (refer to connection drawing, go to page 10), also
ensure the Black lead is connected to earth.
3. Set the top RCD selection knob to the correct range for the RCD under
test.
4. Set the bottom range knob to [1/2I]. The RCD trip indicator will display
a closed symbol .
5. Ensure the display shows the mains voltage.
6. Press the [TEST] button. The instrument should display >1999ms and