2nd Edition

Contents
xvii
9.10 AC power distribution for DC systems 127
9.11 DC power distribution 128
9.12 The effects of electrification 129
9.13 Inspection and maintenance 129
10. Signalling and Train Control 131
10.1 The early history of railway signalling 131
10.2 Modern signalling principles 133
10.3 Track circuits 134
10.4 Point operation, locking and detection 134
10.5 Interlocking 135
10.6 Minimum headways 136
10.7 Home and distant signals 137
10.8 Subsidiary signals 137
10.9 Two aspect colour light signalling 138
10.10 Three aspect colour light signalling 139
10.11 Four aspect colour light signalling 140
10.12 Transmission based signalling 141
10.13 Proof of safety and safety standards 142
10.14 Protection against trains passing signals at danger 143
10.15 Signal protection at level crossings 145
11. Systems and Communications 147
11.1 Getting things done! 147
11.2 Human processes 148
11.3 Good feedback 148
11.4 Interface between operation and engineering 149
11.5 Interface between operator and user 150
11.6 The railway systems pyramid 150
11.7 The railway signalling system 151
11.8 The public address and information systems 152
11.9 Telephones and radio 154
11.10 Closed circuit television (CCTV) 156
11.11 Equipment operation and system maintenance 156
12. Lifts, Escalators and Pumps 159
12.1 Vertical transportation 159
12.2 The development of early lifts 159
12.3 The development of escalators 160