Minimum bending radius?

[main197]

What is the minimum bending radius required for the cable seen in the attached pic? The cable is 500kcmil, inside a control panel, and needs to be connected to the breaker from the top? I could only find the requirement for >1000V. Does the table 312.6(A) or 312.6(B) apply here?

 

[infinity]

Just bend it and land it on the CB. The bend radius in the NEC is for the manufacturer. If the equipment is listed there shouldn't be an issue.

 

[augie47]

As far as deflection of conductors at the breaker. In this case 312.6(A), 6"

 

[don_resqcapt19]

There is are are no bending radius rules in the NEC for single conductors 1000 volts or less.

There is a rule to provide bending space in 312.6(A), but that does not have anything to do with the actual radius you can bend on the conductor.
Correction: The red text is corrected text from my original post.

 

[Another C10]

I believe it was roughly 10 times the diameter of the conductor involved 1" conductor = 10" radius.

 

[main197]

As far as deflection of conductors at the breaker. In this case 312.6(A), 6"

Thanks. How about 312.6 (B)? Does it apply here?

 

[main197]

There is are bending radius rules in the NEC for single conductors 1000 volts or less.

There is a rule to provide bending space in 312.6(A), but that does not have anything to do with the actual radius you can bend on the conductor.

Thanks. Does 312.6 (B) apply here?

 

[augie47]

"B" would apply for distance from breaker terminals to the enclosure IF the conduit entered from the wall opposite the terminals, so in this case, no..it does not apply

 

[Another C10]

There is a rule to provide bending space in 312.6(A), but that does not have anything to do with the actual radius you can bend on the conductor.
Correction: The red text is corrected text from my original post.

If I ever get a moment to look it up I will.

I can't imagine the rule book says nothing about not bending a conductor to the point of creating a hot spot.

 

[Another C10]

If I ever get a moment to look it up I will.

I cheated and googled it .. maybe this is correct.

as posted ..

300.34 Conductor Bending Radius​

The conductor shall not be bent to a radius less than 8 times the overall diameter for nonshielded conductors or 12 times the overall diameter for shielded

 

[roger]

I cheated and googled it .. maybe this is correct.

as posted ..

300.34 Conductor Bending Radius​

The conductor shall not be bent to a radius less than 8 times the overall diameter for nonshielded conductors or 12 times the overall diameter for shielded

You do realize that section is for conductors above 1000v don't you?

 

[infinity]

You do realize that section is for conductors above 1000v don't you?

Yes a common mistake when applying a non-existent bending radius restriction to 600 volt conductors.

 

[Another C10]

You do realize that section is for conductors above 1000v don't you?

I suppose the point that there is a radius limit to a variety of conductors is apparent were some suggest there is no such rule.

Here's another one 320.24

According to NEC Article 320.24, for AC cable, the radius of the curve of the inner edge of any bend shall not be less than 5 times the diameter of the cable.

 

[don_resqcapt19]

I suppose the point that there is a radius limit to a variety of conductors is apparent were some suggest there is no such rule.

Here's another one 320.24

According to NEC Article 320.24, for AC cable, the radius of the curve of the inner edge of any bend shall not be less than 5 times the diameter of the cable.

All of the cable articles have a minimum bending radius in the NEC...there just is not any minimum bending radius for a single conductor rated 1000 volts or less.

 

[tortuga]

I agree with the others there is no NEC code on it, If your looking for something to create a procedure manual or a best practice IEEE has a publication called "IEEE 1185 Recommended Practices for Cable Installations in Generating Stations and Industrial Facilities." might be something in there.