by ericmark »
Sat Dec 04, 2010 1:10 am
There is nothing so simple. The regulations see below do say how the cable and boiler should not effect each other. Also cable has to go vertical or horizontal not diagonal from one device to another so in the future the route can be worked out where not surface.
515.1 Prevention of mutual detrimental influence
Electrical equipment shall be selected and erected so as to avoid any harmful influence between the electrical installation and any non-electrical installations envisaged.
522 SELECTION AND ERECTION OF WIRING SYSTEMS IN RELATION TO EXTERNAL INFLUENCES
The installation method selected shall be such that protection against the expected external influences is ensured in all appropriate parts of the wiring system. Particular care shall be taken at changes in direction and where wiring enters into equipment.
522.1.1 A wiring system shall be selected and erected so as to be suitable for the highest and the lowest local ambient temperatures and to ensure that the limiting temperature in normal operation (see Table 52.1 ) and the limiting temperature in case of a fault (see Table 43.1) will not be exceeded.
522.1.2 Wiring system components, including cables and wiring accessories, shall only be installed or handled at temperatures within the limits stated in the relevant product specification or as given by the manufacturer.
522.2.1 In order to avoid the effects of heat from external sources, one or more of the following methods or an equally effective method shall be used to protect it wiring system:
(i) Shielding
(ii) Placing sufficiently far from the source of heat
(iii) Selecting a system with due regard for the additional temperature rise which may occur
(iv) Local reinforcement or substitution of insulating material.
NOTE: Heat from external sources may be radiated, conducted or convected. e.g.
- from hot water systems
- from plant. appliances and luminaires
- from a manufacturing process
- through heat conducting materials
- from solar gain of the wiring system or its surrounding medium.
