4. Type protection: for how long will the cable have carry fault
current?
Regulation 525 states that the drop voltage from the supply terminals to
the fixed current-using equipment must not exceed for lighting circuits
and for other uses the mains voltage.65A may used safely rather
than 52.Basic Electrical Installation Work
298
Therefore, cable capable carrying 27. Surrounding temperature: cable resistance increases temperature
increases and insulation may melt the temperature too high.5V for other uses 230V installation. Design current: cable must carry the full load current.9V for
lighting and 11. Type cable: PVC, MICC, copper conductors aluminium
conductors.
The factors which influence the current rating are:
1.3.
3. Installed conditions: clipped surface installed with other
cables trunking.
The cable rating, denoted It, may determined follows:
It
Current rating protective device
Any applicable corre
c
ction factors
. They are also given Table 14. Where two cooking appliances
are installed one room, such split-level cookers, one switch may be
used control both appliances provided that neither appliance more
than from the switch (On Site Guide, Appendix 8).
Conductor size calculations
The size cable used for installation depends upon:
● the current rating the cable under defined installation conditions
and
● the maximum permitted drop voltage defined Regulation
525. The volt drop for a
particular cable may found from:
VD
Factor Design current Length run
The factor given the tables Appendix the IEE Regulations and
Appendix the Site Guide.
2.17A cable.
5.
A cooking appliance must controlled switch separate from the
cooker but readily accessible position. That maximum 6
