Siemens siprotec 7SD5 User Manual page 316

2 Functions
• Measuring request from the manual CLOSE detection. The manual CLOSE detec-
• Request to execute a check synchronism measurement from an external closing
• Measuring request from the integrated control function via control keys or via the
The synchronism-check function gives permission for passage „Sync. release"
(No. 2951) of the closing command to the required function. Furthermore, a separate
closing command is available as output indication „Sync.CloseCmd" (No. 2961).
The check of the release conditions is limited by an adjustable synchronous monitor-
ing time T-SYN. DURATION. The configured conditions must be fulfilled within this
time. Otherwise synchronism will not be checked. A new synchronism check se-
quence requires a new request.
The device outputs indications if, after a request to check synchronism, the conditions
for release are not fulfilled, i.e. if the absolute voltage difference Max. Volt. Diff,
the absolute frequency difference Max. Freq. Diff, or the absolute phase angle
difference Max. Angle Diff lie outside the permissible limit values. A precondition
for these indications is that voltages within the operating range of the relay are avail-
able. When a closing command is handled by the integrated control function and the
conditions for synchronism are not fulfilled, the command is cancelled, i.e. the control
function outputs „CO–" (refer also to Section 2.25.1).
Operating Modes The closing check procedure can be selected from the following operating modes:
SYNC-CHECK =
Usync> U-line< =
Usync< U-line> =
Usync< U-line< =
OVERRIDE =
Each of these conditions can be enabled or disabled individually; combinations are
also possible (e.g., release if Usync> U-line< or Usync< U-line> are fulfilled).
Combination of OVERRIDE with other parameters is, of course, not reasonable.
The release conditions can be configured individually either for automatic reclosing or
for manual closing or for closing via control commands. For example, manual closing
and control closing can be allowed in cases of synchronism or dead line, whilst, before
316
tion of the central function control (Section 2.23.1) issues a measuring request pro-
vided this was configured in the power system data 2 (Section 2.1.4.1, address
1151). This requires the device to be informed of the manual closing via binary
input „>Manual Close" (No 356). The release conditions for manual reclosing
apply.
command. Binary input „>Sync. Start MC" (No. 2905) fulfills this purpose.
Unlike the „>Manual Close" (see previous paragraph), this merely affects the
measuring request to the synchronism check function, but not other integrated
manual CLOSE function such as instantaneous tripping when switching onto a fault
(e.g. overreaching zone for distance protection or accelerated tripping of a time
overcurrent stage). The release conditions for manual reclosing apply.
serial interace using DIGSI
tions for manual closure apply.
®
on a PC or from a control center. The release condi-
Release at synchronism, that is, when the critical
values Max. Volt. Diff, Max. Freq. Diff and
Max. Angle Diff lie within the set limits.
Release for energized busbar (UBus>) and de-ener-
gized line (ULine<).
Release for de-energized busbar (UBus<) and ener-
gized line (ULine>).
Release for de-energized busbar (UBus<) and de-en-
ergized line (ULine).
Release without any check.
7SD5 Manual
C53000-G1176-C169-1