Table of Contents
Advertisement
&KDSWHU
Automatic reclosing function (AR)
&RQWURO
For the example (see Figures in Function block diagrams and Sequence examples), the
AR function is assumed to be 2Q and 5HDG\. The breaker is closed and the operation
gear ready, manoeuvre spring charged etc.
AR01-START is received and sealed-in at operation of the line protection. The AR01-
READY output is reset (Ready for a new AR cycle).
Immediately after the start-up of the reclosing and tripping of the breaker, the input (see
figure in Function block diagrams) AR01-CBCLOSED is low (possibly also AR01-
CBREADY at type OCO). The AR Open-time timer, t1, keeps on running. At the end
of the set AR open-time, the three-phase AR time-out (see figure in Function block di-
agrams) is activated and goes on to the output module for further checks and to give a
closing command to the circuit breaker.
%ORFNLQJ RI D QHZ UHFORVLQJ F\FOH
A new start of a reclosing cycle is blocked for the reclaim time after the selected number
of reclosing attempts are performed.
5HFORVLQJ FKHFNV DQG 5HFODLP WLPHU
An AR open-time time-out signal is received from a program module. At three-phase
reclosing, a synchro-check and/or energising check or voltage check can be used. It is
possible to use an internal or an external synchro-check function, configured to AR01-
SYNC. If a reclosing without check is preferred, configure the input AR01-SYNC to
FIXD-ON (set to 1).
Another possibility is to set the output from the internal synchro-check function to a
permanently active signal. Set Operation = Release in the synchro-check function. Then
AR01-SYNC is configured to SYNx-AUTOOK.
At confirmation from the synchro-check or if the reclosing is of single-phase type, the
signal passes on.
At AR01-CBREADY signal of the Close-Open (CO) type, it is checked that this signal
is present to allow a reclosing.
The synchrocheck and energizing check must be fulfilled within a certain period of
time, tSync. If it does not, or if the other conditions are not fulfilled, the reclosing is in-
terrupted and blocked.
The Reclaim-timer defines a period from the issue of a reclosing command, after which
the reclosing function is reset. Should a new trip occur within this time, it is treated as
a continuation of the first fault. When a closing command is given (Pulse AR), the re-
claim timer is started.
175
Advertisement
Table of Contents
