Tait TB9100, Installation And Operation Manual

Page: 56 / 144

56 Installation TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
Auxiliary DC Power
PMU Auxiliary DC
Output
The PMU can provide an auxiliary DC output when it is fitted with the
optional auxiliary power supply board. This board is available with an output
of 13.65 VDC, 27.3 VDC, or 54.6VDC (depending on the model), and is
currently limited to 3 A, 1.5A or 750 mA respectively. This optional power
supply is available on the auxiliary output connector on the rear panel.
The auxiliary power supply is configured by the CSS. Refer to the
“Customer Service Software User’s Manual” for more details.
We do not recommend connecting two or more auxiliary power supply
boards in parallel to increase the current supply to external equipment. In
this situation, the auxiliary board with the highest voltage will try to supply
all the current required, until it goes into current limit and the voltage
reduces to the level where another board will begin to supply power.
Running an auxiliary board continuously in current limit will reduce its life
span and reliability. Also, if one auxiliary board fails or is switched off when
a base station is powered down for some reason, the remaining auxiliary
boards will be unable to supply the required current and will go into current
limit, possibly causing the external equipment to shut down.
It is, however, acceptable to connect two or more auxiliary power supply
boards in parallel (e.g. for redundancy), as long as the current consumption
of the external equipment is less than the rating of one board. This means
that, even if only one auxiliary board is functioning, it will still be able to
supply the current requirements of the external equipment.
Auxiliary DC Power
Supply Connections
Figure 4.12 below shows the standard Tait auxiliary DC power cables
available. Details of the individual connector types are also provided in case
you want to make up your own cables.