METREL EasiPLUS MI 3000 User Manual

MI 3000 EasiPLUS Measurements
33
Notes:
 Parameters set in this function are also kept for all other RCD functions!
 The measurement of contact voltage does not normally trip an RCD. However,
the trip limit may be exceeded as a result of leakage currents flowing through the
PE protective conductor or a capacitive connection between the L and PE
conductor.
 RCD trip-lock sub-function (function selector switch in LOOP position) takes
longer to complete but offers much better accuracy of a fault loop resistance
result (in comparison with the R
L
sub-result in Contact voltage function).
5.3.7 Trip-out time
Trip-out time measurement is used to verify the effectiveness of an RCD. This is
achieved by a test simulating an appropriate fault condition. Trip-out times vary between
standards and are listed below.
Trip-out times according to BS EN 61008 / BS EN 61009:
½I
N
*)
I
N
2I
N
5I
N
General (non-
delayed) RCDs
t

> 300 ms t

< 300 ms t

< 150 ms t

< 40 ms
Selective (time-
delayed) RCDs
t

> 500 ms 130 ms < t

<
500 ms
60 ms < t

<
200 ms
50 ms < t

<
150 ms
Trip-out times according to BS 7671:
½I
N
*)
I
N
2I
N
5I
N
General (non-
delayed) RCDs
t

> 1999 ms t

< 300 ms t

< 150 ms t

< 40 ms
Selective (time-
delayed) RCDs
t

> 1999 ms 130 ms < t

<
500 ms
60 ms < t

<
200 ms
50 ms < t

<
150 ms
*)
Test current of ½I
N
cannot cause trip-out of the RCDs.
For additional information concerning trip-out time measurement refer to the Metrel
handbook
Measurements on electric installations in theory and practice.
How to perform trip-out time measurement
Step 1 Select the RCD function with the function selector switch and use the /
keys to select the Trip-out time function (RCDt). The following menu will be
displayed:
Figure 5.17: Trip-out time measurement menu

METREL EasiPLUS MI 3000 Specifications

General

Brand	METREL
Model	EasiPLUS MI 3000
Category	Test Equipment
Language	English