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3.3-3 Model 4116A, 4118A and 4120A have the following features:
● Battery is not used
All models are not battery-operated, but operate by
the voltage supplied from the system.
● Wiring check
Three LEDs indicate if the wiring of the circuit
under test is correct. The P-E and P-N LEDs
illuminate when the wiring polarity of the circuit
under test is correct.
The Reverse LED is lit when P and N are
reversed.
● Over temperature
Detects overheating of the internal resistor
displaying a warning symbol ( ) and automatically
halting further measurements.
● Overload protection
Halts measurement to prevent damages to the
body when voltage between VL-PE is 260V or
more.
"VL-PE Hi" is shown on the display.
● D-LOK circuit
Model 4120A with unique D-LOK circuit avoids the
need to by-pass most RCD's.
● 15mA Loop
Loop impedance 2000Ω range measurement is
carried out with low test current (15mA). The
current will not cause tripping out involved RCD
even the one with the lowest nominal differential
current (30mA).
● Display
The liquid crystal display has 3 1/2 digits with a
decimal point and units of measurement (Ω, A,
kA,V).
● Manual and Autotest mode
Manual − Press and release the "Press to Test" button. The result will be
displayed for 3s and then the display will revert to AC voltage.
Autotest − The "Press to Test" button can be turned clockwise to lock it
down. In this auto mode, when using distribution board lead
M-7121, tests are conducted by simply disconnecting and
reconnecting the red phase prod of the M-7121 avoiding the
need to physically press the test button i.e. "hands free".
protection
measurement
CAUTION
● The D-LOK circuits may not by-pass some RCD's and this will
result in the RCD tripping out as they would do with a conventional
loop tester. Also, in the case of high sensitivity RCD's rated at
10mA or less the D-LOK circuits may not function.
