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In L-N (L-L) mode the MFT1800 series offers one type of loop test:
2Hi – A 2-wire high current test. A fast 3-4 second test using high test currents.
Where to use:
On ALL circuits except Phase – Earth measurements on RCD protected circuits.
7.2
MAKING A LOOP IMPEDANCE MEASUREMENT
7.2.1 Ze Measurements at the Origin (Phase to Earth)
.1 Set the LEFT rotary range knob to the
L-PE
range.
The MFT automatically uses the Phase and Earth terminals.
.2 Press the Function key <-> to select the “2Hi” mode. The RCD will not trip, so there is no need to use the 3Lo and 2Lo modes.
.3 Connect test leads as below, with the Red test lead connected to the L1 (Red terminal on the MFT and the Green test lead
connected to the Green (L2) terminal.
L
N
E
MCB RCD
g
.4 Press TEST to start the test sequence. This can be automated in SETUP so the test starts when contacting the circuit. See section
10 – Setup.
.5 On completion of the test, the display will show the loop resistance on the large display segments, and the fault current on the
small display segments.
Reverse Polarity warning:
