Product Description

Product Description
68 (98) © Nokia Corporation Draft DN991444
Nokia Proprietary and Confidential Issue 3-0 en Draft
6.6 Power supply unit (HVSx)
The purpose of the power supply unit is to convert the incoming AC or DC supply
voltages into the appropriate DC output voltages. The power is distributed to the
units of the Nokia MetroSite EDGE Base Station and to radio outdoor units (if
used) via the backplane. DC power supplies are reverse polarity protected.
In the case of mains power failure, the AC power supply unit provides a backup
time of 130 ms during which the alarm can be sent. The alarm signal appears
when the input voltage drops below the specified limit. The limit is dependent on
the power supply unit type.
6.6.1 Power supply unit alternatives
The power supply units alternatives available for the Nokia MetroSite EDGE
Base Station are listed in Table 7.
6.6.2 Output voltages
The output voltages from the power supply unit are the following:
• +3.4 VDC, +5.1 VDC, -5.1 VDC, +9.1 VDC, -9.1 VDC, +26.2 VDC and
+55 VDC
• 24 VDC for fan unit
When the fan unit is not in use, the same output voltage feeds power to the heater.
The output voltage to the fan unit and heating is controlled by the I
2
C-bus. The
heating voltage is controlled in five steps ranging from 0 VDC (no heating) to 24
VDC (full heating), the intermediate voltages being 7.2 VDC, 10.9 VDC and 14.7
VDC.
DC power supplies are reverse polarity protected.
Table 7. Power supply unit alternatives
Input voltage PSU type
230 VAC HVSA
110 VAC HVSB
-48 VDC HVSD
+24 VDC HVSC (available for the 800 and 1900
MHz BTS)