User's Manual

USU
 USER MANUAL
DCM000000104
Printed: 03.05.21,10:40
Revision Date:5/21/03
11
The Single-Mode Fiber-Optic interconnections between the Head-End and Remote
Modules are to be made in whatever manner suits the system configuration. For the
CAN Network connections please refer to DCM000000103.
 All Fiber-Optic Cabling must use 9/125 or similar Single-Mode (yellow
jacketed) high-quality cable. This cable should typically have less than 0.5
dBo (optical dB) insertion loss per kilometer.
 From the cable manufacturer's specification, minimum bend radius must
be observed.
 Most Kaval products use SC/APC connectors. Note that the "APC" is
critical. These are angle-polished connectors and are required to reduce
reflections.
 Fiber-Optic Patchcords should be avoided; Fusion-Splices are preferred to
reduce reflections.
 Fiber-Optic Connectors, both on cables and equipment, should always
have their dust caps in place when not in use. The connector tips must be
kept clean and scratch free, and should always be cleaned properly before
being connected.
 Optical Reflections back into laser diodes cause a disturbance in the
lasers gain cavity creating noise and distortion. An OTDR or other Fiber-
Optic Instruments should be used to check optical reflections. Fiber-Optic
Return Loss should be less than -50 dBo.
 There is a 2 to 1 Relationship between optical loss and RF loss. One dBo
(optical dB) of optical loss corresponds to 2 dB of RF loss.
The US Remote Module may be powered by any source of negative ground
+28VDC power capable of delivering 1 Ampere. This includes the optional single US
Remote Module US-PS01 Power Supply...
If the USU Remote Module is being used without a Battery it must be configured to
NOT use a battery. Without a battery the USU will shut down or reset with any
disruption to the AC power. When power is re-established the system will restart
automatically. External batteries may be connected using the CAB000000055
Battery Cable. The USU has a built-in battery charger that will automatically
recharge the attached battery.
Refer to
DCM000000102 "Battery Backup Manual".
For Battery Backup purposes...
Vbat = 24 VDC Ic = 0.1 Ampere Id = 0.75 Ampere
Head-End to Remote
Interconnects
Fiber-Optic
Connections
Power for the
Remote Module
Battery Backup of
Remote Module