Cable Bending Radius

[abrahamJP]

A cable can be bend 90 degrees if we allow enough space for bending radius
ie,12*diameter of armoured cable.

My question is whether a cable can bend 45degress or 30 degrees like above
if we allow space for bending radius OR what is the minimum limit of degrees
that a cable can be bend if we allow space for bending radius as needed?

thanx in advance

Abraham

 

[KllrWolf]

If you are using the minimum bend radius or larger radius throughout the bend, I do not see a reason to limit the degree of turning. What I do not understands is why you would think there would be a restriction on a small bend angle with the same radius as a larger bend.

 

[HornTootinEE]

As long as you obey the bend radius, you are good to go as many 360 degree wraps as you want-so a 270 degree bend, no big deal

 

[7anoter4]

When pulling a cable one has to check also sidewall bearing pressure.
Sidewall bearing pressure is the radial force exerted on the insulation and jacket of a cable
at a bend point when the cable AS under tension. If sidewall bearing pressure is excessive, the conductor will tend to crush the insulation and jacket at the support point.
See : IEEE Std 525-1992 ch. 10.3.1.3 Maximum allowable sidewall pressure:
“Sidewall pressure, P, is defined as the tension out of a bend expressed in pounds divided by the radius of the bend expressed in feet. The sidewall pressure on a cable can be calculated by the following equations:” … eq.6;7;8;9
For instance for a single cable in conduit:
P=To/r
Where:
P is the sidewall pressure, in lb/ft of radius
To is the tension out of the bend, in pounds
r is the inside radius of bend, in feet