7.1.4.3
Breaker contact travel time
The Breaker contact travel time module calculates the breaker contact travel time
for the closing and opening operation. The operation of the breaker contact travel
time measurement can be described with a module diagram. All the modules in the
diagram are explained in the next sections.
Figure 281: Functional module diagram for breaker contact travel time
Traveling time calculator
The travel time can be calculated using two different methods based on the setting
Travel time Clc mode.
When the setting
Travel time Clc mode is “From Pos to Pos”, the contact travel time
of the breaker is calculated from the time between auxiliary contacts' state change.
The opening travel time is measured between the opening of the
POSCLOSE
auxiliary
contact and the closing of the
POSOPEN
auxiliary contact. The travel time is also
measured between the opening of the
POSOPEN
auxiliary contact and the closing of
the
POSCLOSE
auxiliary contact.
Figure 282: Travel time calculation when Travel time Clc mode is “From Pos to Pos”
There is a time difference t
1
between the start of the main contact opening and
the opening of the
POSCLOSE
auxiliary contact. Similarly, there is a time gap t
2
between the time when the
POSOPEN
auxiliary contact opens and the main contact
is completely open. To incorporate the time t
1
+ t
2
, a correction factor needs to
be added with t
open
to get the actual opening time. This factor is added with the
Opening time Cor (= t
1
+ t
2
) setting. The closing time is calculated by adding the
value set with the
Closing time Cor (t
3
+ t
4
) setting to the measured closing time.
When the setting
Travel time Clc mode is “From Cmd to Pos”, the contact travel
time of the breaker is calculated from the time between the circuit breaker opening
1MRS758755 C
Condition monitoring functions
REC615 & RER615
Technical Manual
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