- #1

Dinoduck94

- 30

- 4

- TL;DR Summary
- Help finding the right formulas for calculating reduced EMI when twisting cables.

I have done the maths to work out the Induced Voltage on a communication cable, from a bunch of 3 phase circuits in a panel - with the minimum distance between them I calculated it to be about 1.5nV; but for a larger system where there could be larger loads on the cables I was thinking about what action you can take to reduce the Magnetic Field Density around the cables - without adding additional components.

I know that twisted pairs are used for to do this (to a degree) but I can only find formulas for higher frequencies - is anybody able to point me in the right direction for formulas that calculate how many twists per meter I would need on 3 phase 50Hz circuit (all Tri-rated singles) to negate or reduce its EMI; and what the reduction would be, depending on the number of twists used?

Thanks in advance.

I know that twisted pairs are used for to do this (to a degree) but I can only find formulas for higher frequencies - is anybody able to point me in the right direction for formulas that calculate how many twists per meter I would need on 3 phase 50Hz circuit (all Tri-rated singles) to negate or reduce its EMI; and what the reduction would be, depending on the number of twists used?

Thanks in advance.