Specifications - State of Delaware

SECTION 260533 - RACEWAYS: continued
9. Where different conduits contain circuits of different noise levels the horizontal and
vertical spacing in inches between the outside surfaces of the conduits (or conduit to
cable tray) shall not be less than indicated below (unless specified otherwise, indicated
otherwise, or required otherwise by the equipment manufacturer):
a. Noise Level 1 Circuits: Analog circuits less than 50V, digital circuits less than 12V
or telephone circuits.
b. Noise Level 2 Circuits: Analog circuits greater than 50V or digital circuits greater
than 12V.
c. Noise Level 3 Circuits: 120Vac or DC circuits operating at less than 20 amperes.
d. Noise Level 4 Circuits: AC or DC circuits less than 800V operating with currents
less than 800 amperes.
e. Noise Level 5 Circuits: Circuits over 800Vac or DC and/or over 800 amperes.
f. Additionally, route all conduit containing circuits with a capacity of between 2 kVA
and 5 kVA a minimum of 6 inches from cable tray.
g. Additionally, route all conduit containing circuits with 5 kVA or greater capacity a
minimum of 12 inches from cable tray.
MINIMUM HORIZONTAL AND VERTICAL SPACING BETWEEN
DIFFERENT CONDUIT OUTSIDE SURFACES
(OR CONDUIT TO CABLE TRAY) IN INCHES
Conduit
Noise
Conduit to
Level 1 2 3 4 5 Cable Tray
1 * 1 3 12 12 *
2 1 * 3 9 12 *
3 3 3 * * 6 6
4 12 9 * * * 12
5 12 12 6 * * 12
* = Minimum separation required for installation of locknuts as if adjacent conduit were
terminating in an enclosure.
10. Provide a weatherproof duct seal compound between the conductors and the inner walls
of all conduit that are routed to NEMA 3, 3R, 3S, 4 and 4X enclosures to prohibit
moisture and/or humid air from entering the raceway and condensing.
11. Repair damage to galvanized finishes with a zinc-rich paint recommended by the
manufacturer.
12. Repair damage to PVC finishes with matching touch-up coating recommended by the
manufacturer.
13. Where metallic conduit leaves cast-in-place concrete (to air, to earth or to compacted fill)
coat the conduit 2 inches on either side of the line formed by the finished concrete surface
with a bitumastic asphalt coating.
B. Conduit Installation: Provide threaded, rigid steel zinc-coated conduit where routed lower than
10 feet above the floor in the hangar aircraft bay, embedded in cast-in-place concrete, in
hazardous locations, routed below floor slabs (unless indicated otherwise), when containing
circuits over 600Vac, routed through cast-in-place masonry, or installed outdoors. Follow
minimum requirements in other areas as follows:
1. Use rigid steel zinc-coated conduit in mechanical equipment rooms, shops, electrical
equipment rooms, where exposed to physical damage, and in the aircraft hangar bay
DEAN260533.DOC 260533-5