Alstom MiCOM P545 - 1.21.1 Switch onto fault mode

P54x/EN OP/La4 Operation
(OP) 5-52 MiCOM P543, P544, P545 & P546
OP
(559)
DDB:Phase_A_Undercurrent (864)
20ms
0
|
&
&
&
DDB:CNV Active(556)
DDB:QuarterCycleOV PhB (560)
DDB:QuarterCycleOV PhC (561)
DDB:Phase_B_Undercurrent (865)
DDB:Phase_C_Undercurrent (866)
DDB:CNV Active (556)
&
DDB:CNV TOR Trip (557)DDB:TOR Active (878)
SET:TOR Tripping
-
>
Current No Volts
DDB:CNV SOTF Trip (558)
DDB:CNV Active (556)
&
DDB:SOTF Active (879)
SET:SOTF Tripping
-
>
Current No Volts
ADDB:QuarterCycleOV Ph
P2046ENc
Figure 30 Trip on close based on CNV level detectors (Distance option only)
1.21.1 Switch onto fault mode
The setting
s applied are as follows:
SOTF Status
- SOTF can be activated in three different manners:
1. Enabled by using pole dead logic detection logic. A ‘SOTF Delay’ timer starts if “all
pole dead” condition is detected. Once this timer expires, SOTF becomes enabled
and remains active during the period set on TOC Reset Delay setting.
2. Enabled by an external pulse. SOTF becomes enabled after an external pulse (as a
circuit breaker close command for example) linked to DDB Set SOTF (DDB 488) is
ON. The function remains active for the duration of the SOTF Pulse setting.
3. Enabled by using the two previous methods.
With this feature Enabled, the relay operates in Switch on to Fault mode. Three pole
instantaneous tripping (and auto-reclose blocking) occurs for any fault detected by the
selected zones or/and ‘Current No Volt’ level detectors when in Switch on to Fault mode.
Whether this feature is enabled or disabled, the normal time delayed elements or aided
channel scheme continues to function and can operate to trip the circuit.
TOC Reset Delay
- The SOTF (when enabled by pole dead detection logic) and
TOR features remain in-service for the duration of the TOC
reset delay once the circuit is energized.
SOTF Tripping Link
- While the Switch on to Fault Mode is active, the MiCOM P54x
will trip instantaneously for pick up of any zone selected in
these links. To operate for faults on the entire circuit length it
is recommended that at least Zone 1 and Zone 2 are selected.
If no elements are selected then the normal time delayed
elements and aided scheme provide the protection.