Tait TB8100, User Manual

Page: 102 / 254

92 Part E: Configuring the Base Station
© Tait Electronics Limited December 2007
2. Select the Tx relay operation check box.
3. Adjust the values of the Relay closing settling time (A) and the Delay
before relay opens (B) boxes to reflect the expected delays in switching
the relay.
Minimum battery voltage
The Power configuration area (Configure > Base Station > Miscellaneous)
defines the lowest possible voltage for the DC power input to the PMU.
Three pairs of voltages are displayed, corresponding to the PMU’s different
DC-DC converter options (a nominal 12 V, 24 V, or 48 V input). If there is
no AC power and the battery voltage falls below the value in the relevant
Power shutdown voltage
box, the base stations in the subrack shut down. If
the voltage rises above the value in the Power startup voltage box and the
PMU is fitted with a standby module, the base stations re-start.
Important: The values you define in this area affect any other base
stations in the subrack.
To edit a voltage value, click the up or down arrow alongside.
Base stations with no PMU cannot have their shutdown and startup voltages
adjusted; these voltages are fixed in hardware.
Auxiliary power control
If the PMU is fitted with an auxiliary power supply unit, you may need to
configure it to suit the way it will be used. Generally, its output can be used to
charge batteries or to power other site equipment. This equipment can include
TaitNet trunked modules. These can be powered via the reciter’s system
interface board (additional connection required).
Caution: While the auxiliary power output can be used for more than one
purpose at once, this is not generally recommended. It can result in a short-
circuit and equipment damage. The output is floating. If it is connected to a
negatively earthed battery and to positively earthed auxiliary equipment, a
short-circuit will result.
In the default configuration file, the auxiliary power supply is configured to turn
on only when the base station is mains powered (see the Mains option below).