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Loop test functions
Caution
Although fully protected against over voltage to 440V 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
KT63DL 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
Over temperature. If this symbol shows in the display the temperature of the unit has
reached a point where the performance accuracy could not be guaranteed. Allow the
tester to cool down before proceeding
The KT63DL Loop test function has 2 modes for Loop testing that allow the user to conduct
the most accurate test possible whether or not the circuit under test is protected by an RCD.
High Current mode
For Ze testing at the distribution board or at any point upstream of RCD protection there is
a traditional fast high current test mode. The high current mode is a 2-wire test that enables
the user to test the true impedance of both the Line-Neutral Loop and the Line–Earth Loop
and therefore to establish both the PSC (prospective short circuit current) and the PFC
(prospective fault current) for the installation.
Unlike most testers that only measure the resistance of the Loop, the high current mode
of the KT63DL will measure the true Impedance of the Loop which includes an element of
reactance. This can be significant where the distribution board is close to the mains supply
transformer and is therefore much more accurate than older Loop testing techniques. You
should be aware that because of this there may well be variations in readings compared
to ordinary loop testers or to the no-trip function of this tester, particularly when the
measurement is made near to the mains supply transformer.
No Trip Mode
For Zs testing where the circuit being tested is protected by an RCD there is the new NTL (No
Trip Loop) mode. In this mode testing can be made at sockets on the final circuit without fear
of tripping the RCD.
This is achieved by testing at a current that is too low to trip an RCD on an otherwise
healthy circuit.* The No Trip test is a 3-wire test that also checks the Live, Neutral / Earth
conductors are correctly connected before running the loop test.
