Pop Quiz - Trainees Cooker Question

[gazdkw82]

You referenced 0.725 in your calcs????

I know you got your Ci Rating Factor from Table 52.2 but you need to read 523.9 carefully to understand why this is incorrect.

Well that clearly shows I'm doing something and not actually digesting the information.

523.9 - iv had a good read. Key bits of information. For thermosetting cables, no correction factor for insulation is required.

If a cable is totally surrounded by thermally insualted material for more than 0.5m then the CCC should be x0.5 of that cable (ref C)

 

[Nigel]

Well that clearly shows I'm doing something and not actually digesting the information.

523.9 - iv had a good read. Key bits of information. For thermosetting cables, no correction factor for insulation is required.

If a cable is totally surrounded by thermally insualted material for more than 0.5m then the CCC should be x0.5 of that cable (ref C)

You are correct but in our example the key part of 523.9 is the second paragraph which directs us to App 4.

523.9 is only for cables installed to Ref C and partially going through insulation.

App 4 Tables already take in to account thermal insulation and publish CCC with that taken into account.

 

[gazdkw82]

Ah, your refefencing from 7671?

I was looking in OSG.

Looked in 7671, I see what you mean but I need to read it further to understand it better.

 

[Nigel]

Ah, your refefencing from 7671?

I was looking in OSG.

Looked in 7671, I see what you mean but I need to read it further to understand it better.

7671 needs to be your main reference. The OSG is just a guide.

 

[Richard Burns]

A pictorial reference to demonstrate the differences in applying rating factors or differing installation methods to a cable installed with or passing through insulation.