Power Cable Specifications For A Fully Provisioned Shelf - Nortel Passport 15000 Preparation Manual

144 Chapter 4 Power and grounding preparation
Power cable specifications for a fully provisioned shelf
241-1501-205 5.2S2
The cable specifications for the input power cables terminating at the breaker
interface panel (BIP) must be fed by 1/0 AWG (53.49 mm
fully provisioned Passport 15000 or 20000 switch. The operating company
must provide the power cables up to the BIP. The cable size between the BIP
and the power plant or the BIP and a branch cable must be very flexible 1/
0 AWG cable (such as welding cable). Use cable or an equivalent with these
recommended wire specifications from the National Wire and Cable
Standard:
• 1/0 AWG gauge of Super Flex cable has 2646/34 strands and strand size
with a conductor diameter of 0.437 inches or 96.77 mm
• 1/0 AWG gauge of Welding cable has 1045/30 strands and strand size
with a conductor diameter of 0.431 inches or 94.17 mm
Use the indicated gauge and especially the flexibility of the power cables for
safe, easier, and appropriate installation. Manufacturers of 1/0 AWG
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(53.49 mm ) cable typically have a different number of strands in the cable,
which affects how easily the cable can be bent (flexed) and whether a lug for
1/0 AWG can be easily crimped onto the end of the cable. Because the inside
diameter of a 1/0 AWG lug barrel is 0.39 inches (1 cm) and for a 2/0 AWG
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(67.43 mm ) lug is 0.45 inches (1.1 cm), 2/0 AWG 90-degree offset narrow-
tongued 2-hole lugs (part number A0757391) are typically included with the
BIP. Also, when the insulation is stripped from the cable, the strands tend to
splay slightly and the 1/0 AWG lug is awkward to fit onto the end.
At the rear of the BIP, each input power connection has two studs to ensure a
safe installation of the power cables. The top stud of each pair carries the
power. The bottom stud prevents rotation of the lug from the weight of the
power cable. With secure fastening of a 90-degree (right-angled) 2-hole lug,
arcing and rotation are prevented.
At the rear of the BIP, each A and B feed connection is identified as positive
(+) for the battery return or negative (-) for the battery (-48 V/-60 V dc). Each
connection is also provided with an insulating boot covering a 90-degree
offset narrow-tongued 2-hole lug for the 1/0 AWG flexible cable. The
provided lug is size 2/0 AWG to accommodate differences in the thickness of
1/0 AWG cable by different manufacturers.
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) cables for each
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