Ci - for cable calcs

[ennaress]

Also just revising: trying to apply a rating factor for insulation on a cable calc. Just in theory, it's not for an actual job.
The cable will be clipped direct to joists above ceiling and is covered in >100mm thermal insulation. I cannot find the correction factor for insulation. Advice please!

 

[Andy78]

Table 4A2 in appendix 4 lists all the reference methods

 

[Andy78]

And table 52.2 for cables passing through insulation

 

[Richard Burns]

You generally do not need to apply a rating factor for insulation as you would determine the installation method and then find the appropriate current carrying capacity for the cable in the appropriate table (in this case it sound like twin and earth so table 4D5).
Then you can apply any other rating factors to the tabulated value.