Installation Instructions

R20 1X UBS Macro B T S Hardw are Installation T ask 15: Connecting -48 V DC P ower
Task 15: Connecting -48 V DC Power
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Objective
T ask 15 is performed for -48 V DC UBS Macro BTS only .
The objective of this procedure is to perform T ask 15, which includes:
• A ttaching the contact/lugs and connector on the -48 V DC power input cable wires.
• Connecting the -48 V DC input power cable to the rear of the -48 V DC PSM shelf .
• Routing the loose ends of the wires to the site -48 V DC source for connection to the source.
V erify that the +27 V DC output power cable from the PSM shelf is already
connected to the PDU +27 V DC input power cable. This was performed during
T asks 4 -7.
Frame power cables and connector information
The wire gauge (that is, diameter) depends on the required length of the DC power cable (CC).
Refer to T able 2 -8 for the correct wire size.
The DC connector contact/lug size depends on the wire gauge used for the DC power cable (CC).
Refer to T able 2 -15 for DC connector contact/lug part information.
In order to minimize current imbalance between the feed ( -V) and return (+V) wires used in
the cable:
• Ensure that the wire size, length and gauge, of each wire used in the cable are the same.
• Ensure that contacts/lugs used in the connector are identical and match the gauge of
the wire.
Motorola recommends using 2/0 A WG cables for short cable runs; less than 661.11
cm (21.69 ft).
68P09283A62 -2 2 -63
PRELIMINARY A UG 2007