Airspan AS4000, Installation Manual

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16
Terminate the battery feed and return cables at the isolator/fuse positions, and ensure that
the AC rack is isolated until the commencement of commissioning tests.
DC Power
The cables for the negative DC battery feeds, the 0V returns and the Rack Ground are
detailed in. Should local requirements specify otherwise, it is acceptable for cables of other
colours to be used, however, under no circumstances should the cable sizes be less than that
specified in. The length of the cable supplied will be detailed in the site survey. Separate DC
sources are desirable for maximum protection.
Function Colour Min. Cable Size
Negative Battery Feed -36V
to -60V DC Blue 10 AWG; 6.0mm
2
Zero Volt Positive Battery
Return
Black
10 AWG; 6.0mm
2
Rack Ground Green / Yellow 8AWG; 10.0mm
2
DC Power Cables.
This equipment requires a negative Supply. Ensure that the +ve volt line is connected
to ground or that the supply is floating. The
–
ve battery feed should not be connected to
ground or zero volts under any circumstances.
The maximum DC input should not exceed 60 Volts. Voltages in excess of this are
considered hazardous.
Note 1: Do not insert fuses until instructed to do so in the commissioning stage of installation.
Note 2: If the equipment is installed according to EN 60950 §1.7.9, there should be available
a single disconnect device that isolates the whole equipment., A double-pole external
isolating switch should be provided to isolate the two supplies and should be wall mounted in
the locale of the rack. A label should be included on the unit to direct the user to use the
external isolator for isolation.
The Access Concentrator and Central Terminal Shelves are designed to operate from a -48V
DC supply. In installations where the nominal supply voltage is +24V DC a DC to DC
converter is needed to provide the -48V supply see the schematic diagram below. The DC to
DC converter must be rated at 20 amps or greater at -48V DC