Phasor phasor straight line, having definite length and direction, which rep-
resents scale the magnitude and direction quantity such cur-
rent, voltage impedance.
.
Plastic plugs plastic plug made hollow plastic tube split half its length to
allow for expansion. are both measured volts.) the change energy levels measured
across the load terminals.Glossary terms
381
Personal protective equipment PPE defined all equipment designed worn, held, protect
(PPE) against risk health and safety.
Potential difference The potential difference (p.
Resistance any circuit, resistance defined opposition current flow.
Pressure stress
Force
Area
N/m
)
2
Primary cell primary cell cannot recharged.
PVC/SWA cable installations Steel wire armoured PVC insulated cables are now extensively used on
industrial installations and often laid cable tray.
Reasonably practicable absolute the requirement the regulation absolute, then that regulation must
be met regardless cost any other consideration.
Polyvinylchloride (PVC) PVC used for cable insulation thermoplastic polymer.) defined the cosine the phase angle between the
current and voltage.
Power Power the rate doing work.d.
Resistivity The resistivity (symbol the Greek letter ‘rho’) material defined as
the resistance sample unit length and unit cross-section. Once the active chemicals are
exhausted, the cell must discarded.
Relay relay electromagnetic switch operated solenoid.
Power
Work done
Time taken
W
)
Pressure stress Pressure stress measure the force per unit area.d.
Power factor Power factor (p.
Risk assessments Risk assessments need suitable and sufficient, not perfect.
Protective equipotential bonding This equipotential bonding for the purpose safety.
Rubber Rubber tough elastic substance made from the sap tropical plants. the regulation to
be met ‘so far reasonably practicable’, then risks, cost, time, trouble
and difficulty can considered. Each size plastic plug colour-coded match a
wood screw size.
Risk risk the ‘likelihood’ harm actually being done. This also called the volt drop terminal volt-
age, since emf and p.f
