User Guide Addendum -
MFT1741-MFT1845
Addendum to Section 7.0
Supplementary information for the MFT1741 and
MFT1845 User Guide
Applies to: Loop Impedance Tests (MFT1741 and MFT1845
only).
New feature: Confidence Meter (Patent Applied For) for non-trip
(3Lo) loop impedance tests.
Display information:
Confidence
meter
3Lo (3 wire
non-trip)
Mode indicator
Noise detected
Standard non-trip loop
impedance mode test
indicator
Figure 1. Instrument Display
Confidence Meter Function (Patent Applied For)
Variable test results in a Loop Impedance test are usually
a result of electrical noise on the circuit during the test. The
Confidence Meter analyses this electrical noise and, if necessary,
automatically extends the duration of the test to arrive at an
accurate figure (as per the instruments stated accuracy).
The analogue arc is used to indicate the degree of confidence in
the accuracy of a measurement.
Trim this off
Units of
measurement
Test "in progress"
warning
Non-trip loop impedance test
mode for circuits with Type B
RCD
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