thermal insulation
6. frequency the current (if other than Hz)
7. effects harmonic waves
Serious damage can caused cables are operated for longer periods time above those limits given the tables
and can lead early failure considerable deterioration the cable characteristics.
Note:
The operating voltage system may permanently exceed the rated voltage for the cable %.1132
Cables without jacket may neither used substitute for jacketed cable nor extension cable.
Correction factors may also included the values given for the load rating allow for other conditions, such for
example:
1. cable grouping
2.m.m.s.s. The limiting
temperature with respect the current carrying capacity should not exceeded for the cable insulation and sheath
concerned. Under circumstances may
these values exceeded interaction internal joulean heat (to the material the cable, connections and
terminals) the ambient conditions.
SAFETY REQUIREMENTS THE USE CABLES AND
INSULATED WIRES
.
Current carrying capacity
The nominal cross-section each conductor should selected such that the current carrying capacity not less than
the maximum continuous current that ows through the conductor under normal conditions operation.
The rated voltage expressed the ratio two values, /U, whereby the effective value (r.
The limiting temperatures for the individual cables are given separately our catalogue.
Voltage
The rated voltage for cable the reference voltage for which the cable designed and which serves the
electrical testing requirements.
Included the ned conditions also the method installation for the cable used. The regulations for the
permissible current rating shall observed here for the current.) the voltage
between any insulated conductor and the “earth” (metal covering the cable surrounding medium)
U the effective value (r.
The corresponding VDE and regulations shall observed for the cables used deep mining operations, in
quarrying well for moveable equipment, such cranes with spring-loaded reeling devices for example. These shall
principally not used for connecting Class equipment unless the cable the constructional standard has been
de ned cable for extra light duty and the equipment standard explicitly permits this cable type. ambient temperature
4. alternating current system, the rated voltage cable shall least equal the nominal voltage the
value and direct current system, the rated voltage the system shall not higher than 1,5 times that the
nominal voltage the cable.
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Cables should selected, located and installed that the intended heat dissipation not inhibited and they not
present hazard adjacent materials. type overcurrent protection
3. reeled drummed cables
5.) between any two phase conductors multicore cable system single core
cables
