Low voltage electrical duct bank dimensions

[joshtrevino]

NEC Figure 310.60 states that it is "cable installation dimensions for use with Table 310.60(C)(77) through Table 310.60(C)(86)" - (2011 NEC).

The referenced tables apply to cables rated 2000V and above.

I am installing a 480V feeder in duct bank, as well as several 120V and 208V branch circuits in conduit that is encased in concrete duct bank. Do the duct bank dimensions of Figure 310.60 apply to 600V rated cables as well?

If no, is there another chart / article that defines duct bank dimensions for cables under 600V.

 

[jimdavis]

NEC 310.60 applies only to MV installations (2001-35,000 volts). I am not aware of any NEC dimension or spacing requirements for low voltage duct banks.