Functions
2.7 Teleprotection for Distance Protection (optional)
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
191
2.7.4
Permissive Underreach Transfer Trip with Zone Acceleration Z1B (PUTT)
Principle
Figure 2-85 shows the operation scheme for the permissive underreach transfer trip with zone acceleration. In
the case of a fault inside zone Z1, the transfer trip signal is sent to the opposite line end. The signal received
there causes tripping if the fault is detected in the preset direction inside zone Z1B. The transmit signal can be
prolonged by T
S
(settable at address
2103
Send Prolong.
) to compensate for possible differences in the
pickup times at the two line ends. The distance protection is set in such a way that the first zone reaches up to
approximately 85% of the line length, the overreaching zone, however, is set to reach beyond the next station
(approximately 120% of the line length). On three terminal lines Z1 is also set to approximately 85% of the
shorter line section, but at least beyond the tee-off point. Z1B must securely reach beyond the longer line sec-
tion, even when additional infeed is possible via the tee point.
In address
121
Teleprot. Dist.
the
PUTT (Z1B)
option can be configured. Address
2101
FCT Telep.
Dis.
allows to set the teleprotection scheme to (
ON
).
Figure 2-85
Operation scheme of the permissive underreach transfer trip via Z1B
