Practical Troubleshooting of Electrical Equipment and Control Circuits

Front Cover......Page 1
Copyright......Page 5
Contents......Page 6
Preface......Page 8
1.1 Introduction......Page 9
1.2 Basic principles of electrical machines......Page 20
1.3 AC power systems......Page 27
1.4 Meters used in troubleshooting......Page 30
2.2 Electrical circuits......Page 32
2.3 Reading and understanding electrical drawings......Page 36
2.4 Reading and understanding ladder logic......Page 44
2.5 Wires and terminal numbering......Page 47
3.1 Introduction......Page 50
3.2 Basic principles in using a drawing and meter in troubleshooting circuits......Page 51
3.3 Checks for circuit continuity with disconnected supply......Page 52
3.4 Checks for circuit continuity with live supply......Page 55
3.5 Tests and methods......Page 56
3.6 Testing devices......Page 57
3.7 Circuits......Page 69
3.8 Accurate wiring of circuits and connections......Page 70
3.9 Tests for installation and troubleshooting......Page 74
4.2 Fundamentals of three-phase AC motors......Page 76
4.3 Fundamental of single-phase AC motors......Page 86
4.4 DC motors......Page 89
4.5 Motor enclosures......Page 93
4.6 Motor terminal identification and connection diagram......Page 94
4.7 Motor rating and insulation types......Page 96
4.8 Operating a motor for forward and reverse operation......Page 98
4.9 Motor braking methods......Page 99
4.10 Motor testing......Page 108
4.12 Motor failures and methods to extend its life......Page 114
4.13 Motor control trouble–remedy table......Page 115
4.14 Motor starter check chart......Page 117
5.2 Switches and circuit breakers......Page 120
5.3 Overloads and fault protection......Page 126
5.4 Switchboards......Page 127
5.5 Motor control center......Page 128
6.2 Basic VSD......Page 129
6.3 Power electronic components......Page 131
6.4 Electrical VSDs......Page 140
6.5 Power electronic rectifiers (AC/DC converters)......Page 143
6.6 Gate-commutated inverters (DC/ AC converters)......Page 157
6.7 Overall protection and diagnostics......Page 165
6.8 Installations and commissioning......Page 168
6.9 Power supply connections and earthing requirements......Page 171
6.10 Precautions for start/stop control of AC drives......Page 174
6.11 Control wiring for VSDS......Page 177
6.12 Commissioning VSDs......Page 178
7.1 Basic control circuits......Page 181
7.2 Ladder logic circuits......Page 185
7.3 Two-wire control......Page 186
7.4 Three-wire control – start/stop......Page 187
7.5 Jog/inch circuits......Page 188
7.6 Sequence start and stop......Page 189
7.8 Reversing circuit......Page 191
7.9 Plug stop and anti-plug circuits......Page 195
7.11 Overload protection......Page 197
7.12 Troubleshooting examples......Page 198
7.13 Troubleshooting strategies......Page 200
7.14 Ladder logic design exercise......Page 202
Appendix A: Units and abbreviations......Page 203
B.1 Component testing......Page 204
B.2 Troubleshooting techniques......Page 214
C.2 Air-circuit breakers......Page 221
C.3 Molded-case circuit breakers......Page 222
C.4 Application and selective co-ordination......Page 229
C.5 Earth leakage protection......Page 235
Index......Page 240