when I was an apprentice, one of our lecturers had us copy out from start to finish all of the equations for cable sizing and de-rating on the very back page of our regs book . And where to find the various factors I know that the equations are obviously in the regs but just wondering if anyone on here had a copy or something similar of them all in the same place as I’m wanting to give it to my apprentice to stick in the back of his reg book. He is struggling a bit with the equations and coming to the right answer. Trouble is I can’t find that regs book and I was daft enough not to copy it into each consecutive edition so I may want it a little for myself too