Measurement of the triggering time t
Ai
(t
A
measured during I
A
measurement) for se-
lective RCDs is not available.
The measurement of triggering 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. 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 particular instal-
lation. When measured I
A
is lower than I
n
(most frequent case), then triggering time
t
Ai
will be usually longer than the triggering time measured in function t
A
, which
measures the time at I
n
current:
I
A
< I
Δn
t
Ai
> t
A
where:
t
Ai
= f (I
Δn
)
Therefore, when time t
Ai
is s correct (not too long), it may be assumed that the time
measured in function t
A
would be also correct (it would not be longer).
Phase connected to N terminal instead of L terminal (for
example, exchange of L and N in the mains socket).