Can anyone tell me how to calculate the correction factors for a cable selection I have not done a calculation since college and I am struggling to remember how to calculate it I have examples I done from college but everytime I tried to calculate to find out the amps I was getting lower answer than the ones in the examples I know all the tables to use and that just think I'm doing something wrong with the calculater ?
correction factors
- Thread starter jg90
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Help Support Talk Electrician Forum:
Multiply the c.c.c of the cable by each of the given factors in turn.
So if your correction for thermal is 0.5, and the one for rewirable fuses is 0.75; and your selected cable would be, say, 100A
100 x 0.5 x 0.75 = c.c.c. after correction factors.
Does that help?
So if your correction for thermal is 0.5, and the one for rewirable fuses is 0.75; and your selected cable would be, say, 100A
100 x 0.5 x 0.75 = c.c.c. after correction factors.
Does that help?
post how your trying to do it and someone will tell you what you have done wrong
Technician
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KME; the way your post looks the conductor
size is decreasing and it should be the other
way.
Is it not In divided by 0.5. 0.725?
Correct me if I am wrong.
size is decreasing and it should be the other
way.
Is it not In divided by 0.5. 0.725?
Correct me if I am wrong.
No!
If you read my post properly........
If you`re calculating the corrected current-carrying-capacity of a cable, it will get lower after correction factors applied; NOT higher.
If you`re doing the opposite, and trying to find the necessary tabulated value, then you divide.
:coat
If you read my post properly........
If you`re calculating the corrected current-carrying-capacity of a cable, it will get lower after correction factors applied; NOT higher.
If you`re doing the opposite, and trying to find the necessary tabulated value, then you divide.
:coat
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KME; It never entered my mind that you could be
incorrect but I was interested to read how you applied
those factors.
As I looked at this I had the OSG procedure in my head.
Doc Hudson
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From your answer I presume you have a copy of the on site guide. Appendix F, as well as hiving the tables, also has the formula and procedure written down. As suggested the only way to offer any more advice, is for you to give the actual figures you are tying to calculate and your answer. Then no doubt someone will be able to see which part you are doing wrong.
Doc H.
