Page 284 - Electrical Safety of Low Voltage Systems

285
Electrical Safety of Low-Voltage Systems Dr. Massimo A. G. Mitolo

Euler’s identity, 269
Excitability curve, of cells, 75, 75f
EXCP. See Extraneous-conducive-part
Exposed-conducive-part (ECP), 2, 6, 7f, 9, 10f, 22, 23–25, 38–39, 45, 59–62, 95, 110, 117
External lighting installations, electrical safety in, 253–254, 254f
External overvoltage, 208–212
in external lighting installations, 253–254, 254f
External voltage, 201
Extra-low voltage systems
definition of, 171
functional extra-low voltage systems, 178–179, 178f, 179f
grouping of, 171
protective extra-low voltage systems, 175–178
ripple-free voltage, 171, 172f
separated extra-low voltage systems, 172–175
Extraneous-conducive-part (EXCP), 3, 22, 63–65, 63f, 64f, 110, 113, 118, 129, 145, 147, 149, 234, 240, 247, 251–252
bonding of, 64–65, 64f

F
Fall of potential method, 226
Faraday, Michael, 155
Fault protection, in electrical safety, 9
Fault resistance
in IT grounding systems, 167–169, 168f, 169f
in TT grounding systems, 167–169, 168f, 169f
FELV. See Functional extra-low voltage
Final circuits, 100, 100f
Fuller, Thomas, 223
Functional extra-low voltage (FELV), 171, 178–179, 178f, 179f
Functional insulation, 3
Fundamental electrical conventions
active sign convention, 273, 274f
passive sigh convention, 273, 274f

G
GPR. See Ground potential rise
Ground, 3
Ground electrodes, 45–46
Ground-fault circuit interrupters (GFCIs). See Residual current devices
Ground potential rise (GPR), 49–51, 50f, 51f
Ground resistance, 47, 48f, 49f

H
Hawthorne, Nathaniel, 45
Heart current factor, 82f, 83–84, 84t
Hemispherical electrodes, 46, 46f
Hemispherical shells, 46, 47f
High-resistance grounded (HRG), 3, 4f
High-voltage vs. low-voltage systems, 136
HRG. See High-resistance grounded
Human body
action potential, 73–76, 74f, 75f