Sonel MPI-530-IT - Page 52

OPERATING MANUAL MPI-530-IT version 1.06
50
The meter is ready for measure-
ment.
Value of network voltage and fre-
quency can be read on the dis-
play.
Press START to begin measurement.
Read out the result.
Note:
- Measurement of disconnection time t
AI
(t
A
measured during I
A
measurement) for selective RCD is
not available.
- The measurement of response time t
AI
is not performed as required by applicable standards (i.e with
RCD nominal current I
n
), but with I
A
current measured and displayed during the measurement. But in
most cases where the measurement does not have to be strictly as defined by the standard, this
measurement may be taken into account to assess the proper operation of RCD protection in a par-
ticular installation. When measured I
A
is lower than I
n
(most frequent case), then response time t
AI
will be usually longer than the response time measured in function t
A
, which measures the time at I
n
current. Therefore, when time t
AI
is s correct (not too long), it may be assumed that the time meas-
ured in function t
A
would be also correct (it would not be longer).
Additional information displayed by the meter
U
B
>U
L
!
The touch voltage exceeds a preset U
L
threshold value.
!
Displayed on the right side of the result indicates a fault of
RCD.
No U
L-N
!
Lack of neutral lead that is necessary for I
Δ
n constant and
pulsed with direct current offset
The remaining information is the same as for fault loop measurement (first 7 positions in the table of
section 3.4.1).