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097-55501-01 Revision M – January 2009
TimeHub 5500 User’s Guide 285
Chapter A
Making Ground and Power Connections–Expansion Shelf
Test Point
Test Point
Result
Battery A lead
Battery B lead
0 V
Battery A lead
TB1: Return A
0 V
Battery A lead
TB1: Ground
0 V
Battery B lead
TB2: Return B
0 V
Battery B lead
TB2: Ground
0 V
5. Reconnect the
–
48V battery A and battery B leads to the power terminal blocks
(TB1 and TB2)
–
48V A and
–
48V B terminals.
6. Install the A fuse in the power source fuse panel.
7. Measure the voltage between the
–
48V A and Return terminals on the TB1
terminal block. The multimeter should indicate –42V dc to –56V dc.
8. Install the B fuse in the power source fuse panel.
9. Measure the voltage between the
–
48V B and Return terminals on the TB2
terminal block. The multimeter should indicate –42V dc to –56V dc.
10.Install both 3AG 10 A fuses (fuse A and fuse B) in the front of the shelf. The shelf
is now powered up.
Making Ground and Power Connections–Expansion Shelf
The Expansion shelf has redundant -48VDC power input connections labeled A and
B. Both are located in the upper-right and upper-left corners of the rear panel; the
connections are three-position terminal blocks, as shown in
. The
connections are
not
the same as on the Master shelf.
Install power and ground connections using the procedure described in
Warning:
To avoid possible damage to the shelf and to the office
power supply, connect power wiring as indicated on the rear of the
Expansion shelf. The power connections on the Expansion shelf are
not
the same as on the Master shelf.