Trip-Out Current (Rcd I); Rcd Autotest - METREL MI 3122 Instruction Manual

MI 3122 Smartec Z Line-Loop / RCD

5.1.3 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:
RCD type
AC
A (I
A (I
Maximum test current is I
Trip-out current measurement procedure
Select the
RCD

Set sub-function RCD I.

Set test parameters (if necessary).

Connect test cable to the top of the instrument.

Connect test leads to the item to be tested (see figure 5.2 ).

Press the TEST key to perform the measurement.

Store the result by pressing the MEM key (optional).

Trip-out
Figure 5.5: Trip-out current measurement result example
Displayed results:
I .......... Trip-out current,
Uci ...... Contact voltage at trip-out current I or end value in case the RCD didn't trip,
t .......... Trip-out time.

5.1.4 RCD Autotest

RCD autotest function is intended to perform a complete RCD test (trip-out time at different
residual currents, trip-out current and contact voltage) in one set of automatic tests, guided
by the instrument.
Additional key:
HELP / DISPLAY
Start value
0.2  I
 30 mA) 0.2  I
N
0.2  I
= 10 mA)
N
(trip-out current) or end value in case the RCD didn't trip-out.

function using the function selector switch.
Toggles between top and bottom part of results field.
Slope range
End value
1.1  I
N N
1.5  I
N N
2.2  I
N N
After the RCD is turned on again
27
Testing RCD
Waveform
Sine
Pulsed