ABB RELION 620 Series Technical Manual page 763

1MAC504801-IB E
620 series ANSI
Technical Manual
52
GUID-2AF445C8-388A-42DF-B5B3-070C34F3C7AB V2 EN
Figure 385: A simplified block diagram of SECRSYN in the command mode operation
The closing signal is delivered only once for each activated external closing command
signal. The pulse length of the delivered closing is set with the Close pulse setting.
GUID-0D9A1A7F-58D1-4081-B974-A3CE10DEC5AF V2 EN
Figure 386: Determination of the pulse length of the closing signal
In the command control mode operation, there are alarms for a failed closing attempt
(CL_FAIL_AL) and for a command signal that remains active too long
(CMD_FAIL_AL).
If the conditions for closing are not fulfilled within the set time of Maximum Syn time, a
failed closing attempt alarm is given. The CL_FAIL_AL alarm output signal is pulse-
shaped and the pulse length is 500 ms. If the external command signal is removed too
early, that is, before conditions are fulfilled and the closing pulse is given, the alarm timer
is reset.
Closing
Closing
command
request
25
t = Close pulse
Section 9
Control functions
I
757