Values and tolerances:
− voltage and voltage tolerances,
− frequency and frequency tolerances,
− maximum current allowable,
− prospective short-circuit current.c.c.
Protective equipment: When there any danger changing characteristics supply, the
protective equipment preventing from the consequences shall used.5 Characteristics
Every item electrical equipment selected shall have suitable characteristics appropriate to
the values and conditions which the design the electrical installation based.: phase conductors,
− neutral conductors,
− protective conductor;
− for d.).
. value for a.4.
Power: All electrical equipment selected the basis its power characteristics shall be
suitable for the duty demanded the equipment, taking into account the load factor
and the normal service conditions.
Devices are allowed loaded according their ratings.
For certain equipment, may necessary take account the lowest voltage likely
to occur.
Frequency: frequency has influence the characteristics electrical equipment, the rated
frequency the equipment shall correspond the frequency likely occur the
circuit.: conductors equivalent those listed above.c.g.CONSTRUCTION ELECTRICAL INSTALLATION AND EQUIPMENT 63
6. the current, which the equipment has carry normal
service.c and/or d. Every
electrical equipment and device connected the supply shall comply with following
characteristics:
Nature current available supply: a. the operating time protective
devices any) during which may expected flow. Above that the equipment shall selected with respect the current likely to
be carried abnormal conditions and the period (e.
Current: All electrical equipment shall selected with respect the maximum steady current
(r.m.s.c. values for a.
Voltage: Electrical equipment shall suitable with respect the maximum steady voltage
(r.
Nature and number conductors:
− for a.) likely applied, well overvoltages likely occur.m.c.s
