Should coaxial back boxes be earthed?

[jampot]

Also, should the flexible aluminium ducting of an inline ceiling fan be earthed?

 

[Darkwood]

No ... unless part of a dual point back box with say a socket on the other side.

 

[jampot]

so is it ok to run coaxial inside the same conduit as the power cables in a dual point back box?

 

[telectrix]

NO !. separate conduits.

 

[Darkwood]

Power cables and other cable like data which your aerial would be classed as are different catagories of circuits/cabling and required to be installed away from each other in order to:-

- Limit the risk of electric shock from damage of either/both cables
- Limit interference from induced voltages because the cables run too closed to each other

Other such examples of cabling not to be run alongside mains power/lighting cables are Alarms cables, Phone cables etc whose voltages are classed as extra low and the insulation is also of a lesser value, when you run a cable in parallel for some distance against another cable then the magnetic field around one cable can induce a voltage into the other cable and this is a big problem for sensitive circuits like speakers, alarms, aeriels etc.

 

[jampot]

darkwood, does the regs expressly state coaxial socket can be put in a dual point back box with a single 3 pin socket, provided the coaxial is in seperate conduit? I can find nothing about this.