Chapter 3: System planning
Site planning
Page 3-15
PSU DC power supply
If using the DC input on the AC+DC Power Injector 56V, ensure that the DC power supply meets
the following requirements:
•
The voltage and polarity must be correct and must be applied to the correct PSU terminals.
•
The power source must be rated as Safety Extra Low Voltage (SELV).
•
The power source must be rated to supply at least 1.5A continuously.
•
The power source cannot provide more than the Energy Hazard Limit as defined by
IEC/EN/UL60950-1, Clause 2.5, Limited Power (The Energy Hazard Limit is 240VA).
PSU AC power supply
Always use an appropriately rated and approved AC supply cord-set in accordance with the
regulations of the country of use.
PSU location
Find a location for the PSU (AC Power Injector 56V, AC+DC Enhanced Power Injector 56V or
CMM5) that meets the following requirements:
•
The AC Power Injector 56V can be mounted on a flat surface.
•
The AC+DC Enhanced Power Injector 56V can be mounted on a wall or other flat surface.
•
The CMM5 Power and Sync Injector can be installed in a standard 19-inch rack.
•
The PSU is kept dry, with no possibility of condensation, flooding or rising damp.
•
The PSU is located in an environment where it is not likely to exceed its operational
temperature rating, allowing for natural convection cooling.
•
The PSU can be connected to the ODU drop cable and network terminating equipment.
•
The PSU can be connected to a compatible power supply. AC+DC Enhanced Power Injector
56V: the use of DC supplies of less than 55V will reduce the usable distance between the
PSU and ODU.
PTP-SYNC location
If PTP-SYNC is to be installed, consider the following factors when selecting a site:
•
Indoor location with no possibility of condensation.
•
Accessibility for viewing status indicators.
•
The maximum cable length between the PSU and the PTP-SYNC is 2 m (6 ft).
GPS receiver location
Mount the GPS receiver for PTP-SYNC at a location that meets the following requirements:
•
It must be possible to protect the installation as described in