METREL MI 3125 - RCD Testing: General Data and Parameters

MI 3125 EurotestCOMBO Testing RCD
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5.5 Testing RCDs
Various test and measurements are required for verification of RCD(s) in RCD protected
installations. Measurements are based on the EN 61557-6 standard.
The following measurements and tests (sub-functions) can be performed:
 Contact voltage,
 Trip-out time,
 Trip-out current,
 RCD autotest.
See chapter 4.1 Function selection for instructions on
key functionality.
Figure 5.17: RCD test
Test parameters for RCD test and measurement
TEST RCD sub-function test [RCDt, RCD I, AUTO, Uc].
I
ΔN
Rated RCD residual current sensitivity I
ΔN
[10 mA, 30 mA, 100 mA, 300 mA,
500 mA, 1000 mA].
type
RCD type [ , ], test current waveform plus starting polarity [ , , , ].
MUL
Multiplication factor for test current [½, 1, 2, 5 I
ΔN
].
Ulim Conventional touch voltage limit [25 V, 50 V].
Notes:
 Ulim can be selected in the Uc sub-function only.
The instrument is intended for testing of General (non-delayed) and
S
elective (time-
delayed) RCDs, which are suited for:
 Alternating residual current (AC type, marked with symbol),
 Pulsating residual current (A type, marked with symbol).
 Pulsating residual current (A type, marked with symbol).
Time delayed RCDs have delayed response characteristics. As the contact voltage pre-
test or other RCD tests influence the time delayed RCD it takes a certain period to
recover into normal state. Therefore a time delay of 30 s is inserted before performing
trip-out test by default.