METREL MI 3125 - Trip-out Current (RCD I) Measurement

MI 3125 EurotestCOMBO Testing RCD
35
Displayed results:
t ...........Trip-out time,
Uc........Contact voltage for rated I
ΔN
.
5.5.3 Trip-out current (RCD I)
A continuously rising residual current is intended for testing the threshold sensitivity for
RCD trip-out. The instrument increases the test current in small steps through
appropriate range as follows:
Slope range Waveform
RCD type
Start value End value
Note
AC
0.2
×I
ΔN
1.1×I
ΔN
Sine
A (I
ΔN
≥ 30 mA) 0.2×I
ΔN
1.5×I
ΔN
A (I
ΔN
= 10 mA) 0.2×I
ΔN
2.2×I
ΔN
Pulsed
Both models
Maximum test current is I
Δ
(trip-out current) or end value in case the RCD didn’t trip-out.
Trip-out current measurement procedure
 Select the RCD function using the function selector switch.
 Set sub-function RCD I.
 Set test parameters (if necessary).
 Connect test cable to the instrument.
 Connect test leads to the item to be tested (see figure 5.18).
 Press the TEST key to perform the measurement.
Trip-out After the RCD is turned on again
Figure 5.21: Trip-out current measurement result example