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5.2.3 No-trip loop testing using the RED/GREEN test leads
The [No-Trip] loop test can be carried out where a power socket is not available using the 2 wire lead set.
5.2.3.1 Phase to earth loop test
1.
Select the [No Trip] test range on the lower range knob, and [Z] on the upper range knob where present.
2.
Connect the RED and GREEN test leads to the instrument.
3.
Connect the RED test lead to the
Phase
conductor and connect the GREEN test lead to the
Earth
conductor.
4.
The loop test will automatically start and the [
] symbol will appear, and remain on, for the duration
of the test.
5.
After a test period of 10 seconds the measured loop value is displayed.
6.
To repeat the loop test, press the [
TEST
] key.
The symbols [
] and [
] may appear during the test. Refer to section 5.1.1.2 (Symbols) for an explanation of
their meaning.
5.2.3.2 Phase to Neutral and Phase to Phase loop testing
Both Phase to Neutral and Phase to Phase testing can be made using the No-Trip test, as described above for the
Phase to earth test. However a High current test will not trip RCDs when making either a P-N or P-P test, and it is
recommended that a High current test is used for both these measurements.
5.2.4 Earth bonded metalwork testing
Repeat the test 5.2.3.1 (Phase to Earth) test above, but with the GREEN lead connected to the exposed
metalwork providing the earth return path.
5.3 High current loop test [High Current]
The [
High Current
] loop test performs a 2-wire high current test at around 4 A on a 230 V supply, providing a
very stable and fast loop test.
WARNING: This test is designed for non-RCD protected circuits.
Due to the high currents used the instrument adds a brief pause between tests to prevent
overheating. This is indicated by the [
] symbol and appears for a nominal 5 seconds between
tests for voltages <260 V and 10 seconds for voltages above 260 V.
5.3.1 High current Phase to Earth loop test
1.
Select the [
High Current
] test range on the lower range knob, and [Z] on the upper range knob where
present.
7.
Connect the RED and GREEN test leads to the instrument.
8.
Connect the RED test lead to the
Phase
conductor.
9.
Connect the GREEN test lead to
Earth
conductor.
This test can also be performed using the mains socket test lead, using the RED and GREEN connectors).
10.
The loop test will automatically start and the [
] symbol will appear, and remain on, for the duration
of the test.
11.
The measured loop value is displayed.
Note: The AUTO START function will not operate if the instrument is connected to a live supply BEFORE the
range knob is moved to [High Current]. This is to prevent tripping of RCDs by accidentally selecting the [High
Current] test instead of [No Trip] test, with the leads connected to the supply. In which case pressing the [TEST]
button will start a test.
Subsequent connection of test leads will run the AUTO START test.
AUTO START can be disabled in the SETUP procedure as described in section 8.
5.3.2 High current Phase to Neutral loop test
Repeat test 5.3.1 with the Green lead connected to the Neutral conductor.
This test can also be performed using the mains socket test lead, using the RED and BLUE connectors.
5.3.3 High current Phase to Phase loop test
Repeat test 5.3.1 with the Green lead connected to another phase conductor.
