Tait TB9100, Installation And Operation Manual

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18 Description TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
When the battery voltage rises to the configured startup setting, power is
resumed to the DC supply.
Auxiliary Power
Control
If the PMU is fitted with an auxiliary power supply unit, its output can be
used to power other site equipment or to recharge the DC battery supply
when the base station is running off the AC supply. You will need to
configure it to suit your requirements.
Power Distribution
This section details how the input power feed is distributed throughout the
base station system to power its various sub-systems. The high level block
diagrams in
Figure 1.5 on page 19 show the power distribution paths in base
station systems.
The TB9100 can receive input power from either the AC or DC input.
Internal seamless switching between the AC or DC input ensures there are
no power interruptions should a changeover occur between the two inputs.
The base station will default to the AC input if both AC and DC inputs are
provided.
The AC converter has a series switch which isolates the mains input from
the converter. The DC input, however, has much higher current ratings, and
supports an on/off switch on the converter only.
The outputs from both the AC and DC high power converters are added
together and fed to the PA via the PA1 and PA2 outputs. The auxiliary
output is also tapped off this summed output.
Base stations fitted with a 12V PA do not require a PMU. In this case the
DC input is connected directly to the PA, where it is fed to the internal
boost regulator board. This board provides a 12 VDC output for the reciter
and a 28VDC output for the PA circuit boards.
The reciter input power feed is distributed to all internal reciter boards.
Local regulation ensures that noise and common mode interface signals are
kept to a minimum between sub-assemblies. Various power supplies in the
reciter further power and isolate critical sub-sections.
The reciter also powers the control panel, via a backpower protection diode.
The system control bus is used to route power from the reciter to the control
panel. When a reciter is powered and plugged into the control bus, if a
control panel is connected there will always be a reciter present to drive the
control bus functions.