ABB RELION Series Technical Manual page 630

Section 9
Control functions
624
module has not removed the external command signal after the closing operation. To
avoid unnecessary alarms, the duration of the command signal should be set in such
a way that the maximum length of the signal is always below Maximum Syn time + 5s.
Maximum Syn time
GUID-4DF3366D-33B9-48B5-8EB4-692D98016753 V2 EN
Figure 321: Determination of the alarm limit for a still-active command signal
Closing is permitted during Maximum Syn time, starting from the moment the external
command signal CL_COMMAND is activated. The CL_COMMAND input must be kept
active for the whole time that the closing conditions are waited to be fulfilled.
Otherwise, the procedure is cancelled. If the closing-command conditions are fulfilled
during Maximum Syn time, a closing pulse is delivered to the circuit breaker. If the
closing conditions are not fulfilled during the checking time, the alarm CL_FAIL_AL
is activated as an indication of a failed closing attempt. The closing pulse is not
delivered if the closing conditions become valid after Maximum Syn time has elapsed.
The closing pulse is delivered only once for each activated external command signal,
and a new closing-command sequence cannot be started until the external command
signal is reset and reactivated. The SYNC_INPRO output is active when the closing-
command sequence is in progress and it is reset when the CL_COMMAND input is reset
or Maximum Syn time has elapsed.
Bypass mode
SECRSYN can be set to the bypass mode by setting the parameters Synchrocheck
mode and Live dead mode to "Off" or alternatively by activating the BYPASS input.
In the bypass mode, the closing conditions are always considered to be fulfilled by
SECRSYN. Otherwise, the operation is similar to the normal mode.
Voltage angle difference adjustment
In application where the power transformer is located between the voltage
measurement and the vector group connection gives phase difference to the voltages
Close pulse
5s
1MRS758755 A
REC615 and RER615
Technical Manual