formulas

[bonio78]

How do all, me again can any one tell me what these two formulas are and how you could use them
Adiabatic Equation
Fusing Factor
thanks for your help

 

[m4tty]

Adiabatic equation is for cpc size.

Fusing Factor =

Fusing Current
Current Rating

ie, a 20a fuse which blows when 25a is put thorugh it would be 25/20 = 1.25

So fusing factor is 1.25 for the above example

HTH

 

[Guest123]

Agree with Matty.

Adiabatic to determine the minimum size of CPC for comparision with existing.

Fusing factor is used to determine the level of protection provided by a device i.e how fast it will operate.

The fusing current can be found by using the time for current graphs in Appendix 3 of BS 7671.