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392.10(B)(1)(a) - Single conductor cables 1/0 or larger
- Thread starter NAZ55
- Start date
Art. 392.10(B)(1)(a):
“Single-conductor cable shall be 1/0 AWG or larger
and shall be of a type listed and marked on the surface for
use in cable trays”.
This is not a new limitation but it was also in previous editions.
In my opinion- since the method of installation in cable tray requires a certain force to be applied on this cable if the power cable conductor will be less than 1/0 AWG it could be damaged.
IEEE 525/1992 limit the pulling tension to 1000 lbs[4.45 kN] -pulling a single-core cable with a basket-grip.
The required pulling force depends on many factors as the run length, the lubrication, the number, size and shape of the bends, and other.
Other standard as VDE 0298-1/3 for instance-limits the pulling force[basket grip pulling ] to:
P=3*d^2 [P in N, d overall diameter in mm] for single-core cable that means for 1/0 AWG approx. 500 lbs.
If there are other cables to be installed in the same cable tray pulling a larger diameter cable when the small cable is already laid it could damage the small cable. A rule of a thumb the diameter ratio has to be less than 3.
“Single-conductor cable shall be 1/0 AWG or larger
and shall be of a type listed and marked on the surface for
use in cable trays”.
This is not a new limitation but it was also in previous editions.
In my opinion- since the method of installation in cable tray requires a certain force to be applied on this cable if the power cable conductor will be less than 1/0 AWG it could be damaged.
IEEE 525/1992 limit the pulling tension to 1000 lbs[4.45 kN] -pulling a single-core cable with a basket-grip.
The required pulling force depends on many factors as the run length, the lubrication, the number, size and shape of the bends, and other.
Other standard as VDE 0298-1/3 for instance-limits the pulling force[basket grip pulling ] to:
P=3*d^2 [P in N, d overall diameter in mm] for single-core cable that means for 1/0 AWG approx. 500 lbs.
If there are other cables to be installed in the same cable tray pulling a larger diameter cable when the small cable is already laid it could damage the small cable. A rule of a thumb the diameter ratio has to be less than 3.
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