
Security checks to comparison
AND (see Figure 2-7) include (1)
low channel signal blocking, (2)
lockout for sustained low channel
signal, (3) channel noise clamp,
and (4) receive guard block. For
the phase subsystems, a trip signal
occurs if comparison AND has an
output for more than 3 ms (4 ms
for the ground subsystem).
2.2
Direct Transfer-
Trip Systems
Direct transfer-trip systems
provide circuit-breaker tripping at
remote or receiver terminals,
without any supervision by fault
detectors. The most important
consideration in a direct transfer-
trip system is the type of channel
applied. The communications
equipment must carry the total
burden of system security and
dependability.
Direct transfer-trip systems are
applied for:
• Line protection with non-
permissive under reaching
transfer-trip systems.
• Transformer protection
where there is no circuit
breaker between the trans-
former and transmission
line.
• Shunt reactor protection.
• Remote breaker failure
protection.
Page 2–10
December 1996
TCF–10B System Manual
Technologies, Inc.
Trip Positive
Trip Positive
Trip Negative
Trip Negative
Local Positive
Local Positive
Local Negative
Local Negative
F
Internal Line Up
Keying
Square
Wave
G
H
1
0
1
0
Trip Coincidence
Remote Square Wave
Shaded Portion is
Trip Coincidence
Note:
Similar Comparison Occurs
at Terminal H.
a) Normal Internal Fault
Trip Positive
Trip Positive
Trip Negative
Trip Negative
Local Positive
Local Positive
Local Negative
Local Negative
I
Key
F
Internal Line Up
Keying Square Wave is
Steady Trip Negative
G
H
1
0
1
0
Trip Coincidence
Remote Square Wave
Shaded Portion is
Trip Coincidence
Note:
Similar Comparison Occurs
at Terminal H.
c) Internal Fault with Outfeed (Comparison at Strong Terminal)
Keying
Square
Wave
Trip Positive
Trip Positive
Trip Negative
Trip Negative
Local Positive
Local Positive
Local Negative
Local Negative
I
Key
F
External Line Up
G
H
1
0
1
0
Trip Coincidence: None
Remote Square Wave
Note:
Similar Comparison Occurs
at Terminal H.
b) External Fault
Note:
Local Square
Waves "Nest" within
Remote Square Wave
to Provide Security
Figure 2–9. Response of Segregated Phase Comparison
System with Offset Keying.
Summary of Contents for TCF-10B
Page 2: ......
Page 32: ...Page 1 18 April 1997 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 49: ...December 1996 Foigure 2 15 TCF 10B Catalog Numbers Module Style Numbers 1355D19 Page 2 17 ...
Page 57: ...Page 3 8 April 1997 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 58: ...April 1997 Figure 3 3 TC 10B TCF 10B Mechanical Outline Drawing 1354D48 Page 3 9 ...
Page 62: ...Page 4 2 January 1996 TCF 10B System Manual Technologies Inc Figure 4 1 Extender Board ...
Page 88: ...Page 6 12 April 1997 TCF 10B System Manual Technologies Inc 8 RECEIVER LOGIC ...
Page 89: ...April 1997 Page 6 13 Chapter 6 Routine Adjustment Procedures 6 ...
Page 95: ...April 1997 Figure 7 1 TCF 10B Functional Block Diagram 1354D13 Page 7 5 ...
Page 117: ...Page 10 12 January 1996 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 123: ...Page 11 6 Figure 11 2 TCF 10B Transmitter Schematic 1355D71 April 1997 ...
Page 129: ...Page 11 12 April 1997 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 143: ...Page 13 6 April 1997 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 167: ...Page 14 24 April 1996 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 189: ...April 1997 Figure 16 7 2 Frequency Directional Comparison Functional Block Diagram Page 16 7 ...
Page 190: ...Page 16 8 Figure 16 8 3 Frequency Directional Comparison Functional Block Diagram April 1997 ...
Page 204: ...April 1997 Figure 16 11 TCF 10B Receiver Logic Schematic CF30RXLMN Sheet 1 of 3 Page 16 21 ...
Page 205: ...Page 16 22 Figure 16 12 TCF 10B Receiver Logic Schematic CF30RXLMN Sheet 2 of 3 April 1997 ...
Page 206: ...April 1997 Figure 16 13 TCF 10B Receiver Logic Schematic CF30RXLMN Sheet 3 of 3 Page 16 23 ...
Page 214: ...Page 17 8 January 1996 TCF 10B System Manual Technologies Inc USER NOTES ...
Page 232: ...Page 18 18 April 1997 TCF 10B System Manual Technologies Inc USER NOTES ...