User Manual

Understanding the Digital Module Kit
IP-RN 8000 Installation & Commissioning Guide 21
Understanding the Timing Frequency Unit module
The Timing Frequency Unit (TFU) provides system timing from Global Positioning System (GPS) antenna.
See Figure 11
and Table 12.
The primary TFU module installs in slot 2. The optional redundant TFU installs in slot 6.
The TFU is field-replaceable and hot swappable. Hot swapping a TFU is service disrupting if it is the active
TFU in a redundant configuration. Therefore switching service to the standby TFU in redundant systems
before replacing the module is recommended.
For information about installing the TFU:
• See Understanding the installation process
on page 40.
• See Understanding the module installation process
on page 104.
Figure 11 Timing Frequency Unit
TFU
Power
Alarm
Standby
Active
Timing Frequency Units (TFUs)
slot 2 (primary) & slot 6 (redundant)
Captive screw
Captive screw
Top latch
Bottom latch
LEDs
10 Mhz Out