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Loop Impedance Testing
Principle of Measurement – No-Trip
The No-Trip Line-Earth loop range measures the same circuit value ZI using a two-stage technique.
In the first stage the Live-Neutral loop
impedance ZLN is measured using the same
principle as for the Live-Earth loop.
The second stage is similar to Hi-I but operates
at a low current to avoid tripping RCDs.
CAUTION
Although fully protected against over voltage to 550VAC this tester should only be used
on a 230V supply.
Important note for calibration check box users: The smart loop test system used by the
KT63 PLUS is immune to sudden high value changes such as voltage spikes. As a result
when changing calibration or check box loop values the tester or the supply must be
switched off between changes of calibration values.
The KT63 PLUS Loop test function has 2 modes for Loop testing that allow the user to conduct
the most accurate test possible depending whether or not the circuit under test is protected by
an RCD.
Intermittent Operation
The KT63 PLUS is designed for a large number of loop tests in rapid succession. In the unlikely
condition this limit is exceeded a thermometer will be shown on the display until the unit cools
down. Testing will be inhibited while the thermometer is shown.
Mains Supply Wiring And Voltage Test
When first connected to a mains supply the KT63 PLUS will automatically conduct a safety test to
ensure that the Live, Neutral and Earth conductors are all connected correctly and that the supply
voltage is in the acceptable range (207-253V)
If all is well the VOLTAGE/POLARITY warning LED will light Green and the supply voltage will be
displayed in the primary display area.
In the event of a problem with either the mains voltage supply or reversed connections the
VOLTAGE/POLARITY warning LED will light Red, a warning tone will be sounded and testing will be
inhibited.
This condition will be indicated for your safety.
