The radius of the curve of the inner edge of the bends shall be
at least 6 times the external diameter for armoured cable.
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6x od
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For Unshielded cables, it will 8 multiplies cable diameter and for shielded cables, it is 12 multiplies the cable diameter. However, the smaller the bend radius, the greater is the material flexibility.
Regards
Kelechi
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It depends on the cable. 0 to 5000 volts the minimum bending
radius is 6 x diameter of the cable. Above 5000 volts the minimum
bending radius is 8 x the diameter of the cable.