![Symmetricom TimeHub 5500 User Manual Download Page 106](http://html.mh-extra.com/html/symmetricom/timehub-5500/timehub-5500_user-manual_1419592106.webp)
106 TimeHub 5500 User’s Guide
097-55501-01 Revision M – January 2009
Chapter 3 Installing the TimeHub 5500
Making Ground and Power Connections
1. Remove both fuses from the front panel of the shelf. You will replace them at the
end of the installation procedure.
2. Locate the power terminal blocks on the rear panel (
).
Figure 3-10. Power and Ground Connections on the Master Shelf
3. Using 1 mm
2
/ 18 AWG (minimum) stranded wire, connect primary power to the
A terminal screws and secondary power to the B terminal screws. Symmetricom
recommends that you use a #6 spade lug termination for each power lead. If
separate power supplies are not available, connect both A and B power from the
same source.
The branch circuit over-current protection device shall be a maximum of
15 Amperes.
Testing Power Connections
To verify that the power connections to the TimeHub 5500 Main shelf are correct,
follow the steps in this section. Use a digital multimeter (Fluke 77 or equivalent) to
make the measurements. Refer to
, and
. Use
this procedure for Master/Remote and Expansion shelves.
1. Remove all fuses that supply power to the shelf from the fuse panel and from the
front of the shelf.
2. Ensure that no Clock, Management, or Output Driver cards are installed in the
shelf.
3. Disconnect the
–
48V battery A and battery B leads from the shelf power terminal
blocks TB1 and TB2 (
). (Leave the Return battery
leads connected to the shelf.)
Caution:
To avoid damage to the shelf, remove the fuses in the fuse
panel which powers the TimeHub 5500 Shelf before you make power
connections. Also make sure to remove the fuses from the TimeHub
5500 shelf before connecting power.
A. TB1 Connections
(Office Battery A)
B. TB2 Connections
(Office Battery B)