Trunking Factors

ziddygango · Mar 6, 2024

Hi, I am currently doing a level 2 (2365). We have been doing trunking factors and I am not sure about if you need to apply the 45% space regulation to the factor. For example, if I have trunking of 50 mm x 50 mm the trunking factor is 767. I have 1.5 mm solid thermosetting cables that have a factor of 8.6. So will the maximum number of cables I can fit into the trunking is

767/8.6 = 92

or does the trunking factor not take into account the 45% regulation and therefore, the max number of cables you can fit is

Trunking factor with 45% applied = 767 * 0.45 = 345

345/8.6 = 40 cables

So which one is correct? Does the trunking factor already account for the 45% or do you have to apply the 45% yourself?

westward10 · Mar 7, 2024

Yes your trunking factor has taken into account the 45% spacing so you do not need to apply this.
Where have you got the factor of 767 for the trunking from as that seems very low for 50 × 50.

ziddygango · Mar 10, 2024

westward10 said:
Yes your trunking factor has taken into account the 45% spacing so you do not need to apply this.
Where have you got the factor of 767 for the trunking from as that seems very low for 50 × 50.

Thanks for clearing that up mate. The 767 is from the onsite guide, you were right it was actually for 50 mm x 38 mm trunking. Again thanks.