Tait International Limited TBCK4B Manual Do Utilizador

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DRAFT 4 
TB9400 Installation and Operation Manual
Description
23
© Tait Electronics Limited September 2011
1.7.4
Power Management and Distribution
The PMU manages the supply of power to ensure uninterrupted operation 
of the 
base station
. A range of parameters is monitored and these can trigger 
alarms that are sent to the reciter. Alarms can be monitored via the web 
interface, and are also recorded in the reciter’s internal log file.
AC to DC 
Changeover
When the PMU has an AC and a DC module, the 
base station
 can be 
powered by either the AC (mains) or the DC (battery) supply. The 
base 
station
 will default to the AC supply if both supplies are provided. If the AC 
supply becomes unavailable, a seamless changeover from the AC to DC 
supply takes place, providing that the battery voltage is above the configured 
minimum. You can use a web browser to check whether the 
base station
 is 
running on battery or mains power.
DC Operation
When the 
base station
 is running off the DC supply and the battery voltage 
falls below the configured minimum, the 
base station
 will enter battery 
protection mode to protect the battery and 
base station
 equipment. The 
standby power supply card maintains the power to the PMU microprocessor, 
while the rest of the PMU is shut down. When the battery voltage rises to 
the configured startup setting, power is resumed to the DC supply. Refer to 
 for more detailed information.
Auxiliary Power 
Control
The output from the auxiliary power supply board can be used to power 
other site equipment. The maximum output is 40 W.
Distribution
 shows how power is distributed to modules in the subrack. The 
28 VDC output from the PMU is fed directly to the 100 W PA and 50 W 
PA1, and to the other modules via the subrack interconnect board. Power 
to the reciters and front panel is current-limited by self-resetting fuses on the 
subrack board.
The AC converter has a series switch which breaks the phase input to the 
converter. The DC input, however, has much higher current ratings. Its 
switch does not disconnect power from the DC converter itself, but disables 
the converter by switching off its control circuitry.
The outputs from both the AC and DC high power converters are added 
together and fed to the modules via the high-current outputs. The auxiliary 
output is also tapped off this summed output.