CopperOptics 150-1619-11, Technical Practice, Page: 30 / 52

Installation and Test 950-719-111-03, Revision 03
24 June 29, 2000 PCS-719 List 1A
Redundant Shelf Powering
In this configuration, each circuit card in the COT shelf receives power from two –48 Vdc sources. If one –48 Vdc
source is lost, the other –48 Vdc source provides power to the shelf circuit cards. Each –48 Vdc source should be
fused according to
Table 22 on page 20 and Table 23 on page 21 .
A four-position jumper is in place on the TB1 block ( Figure 7 ). This jumper shorts all of the 48 VDC inputs
together to prevent an alarm condition when only one input feed wire is connected. To provide redundant shelf
powering:
1 Ensure that the ground connection is in place.
2 Remove the four-position jumper from TB1.
3 Cut the four-position jumper in half, snipping out a small strip to ensure a gap between the two pieces when
they are replaced.
4 Replace the two pieces on the TB1 block, connecting TB1-1 to TB1-2 with one piece; then TB-3 to TB-4 with
the second piece.
5 Connect a wire from the –48A-LOW terminal of TB1 to the CO A battery supply terminal at the fuse panel.
6 Connect a wire from the –48B-HIGH terminal of TB1 to the CO B battery supply terminal at the fuse panel.
7 Connect a wire from the Battery Return terminal in position 5 of TB1 to the CO A battery return at the fuse
panel.
8 Connect a wire from the Battery Return terminal in position 6 of TB1 to the CO B battery return at the fuse
panel.
Figure 7. Redundant Shelf Power Wiring