Antenna Cables; Power Supply; Current Consumption - ASCOM telePROTECT 900 System Installation

System Installation
On Site Paging System
5.5

Antenna Cables

Keep coax cables between transmitter/receiver and antenna as short as possible. Use only
cable type RG-8 or RG-213. The attenuation in these types is about 0.8 dB/10m at VHF,
and 1.5 dB/10m at UHF. (6 dB attenuation reduces coverage by 50%.)
6

Power Supply

All units use 12.5 V DC and can be powered separately, but normally a common power
supply feeds all the units that are placed together in one location. The power supply is
connected to screw terminals on one of the units and then connected in series to the
other units. The wiring from the power supply must be dimensioned so that the voltage
drop to the modules does not exceed 0.5 V at max load. If the total loading exceed the
capacity of the connected power supply, an additional power supply should be used, see
below.
Figure 11. Units powered by two power supplies.
7

Current Consumption

When calculating total current load always use the max consumption for each unit:
Control Keyboards max Load (A)
T900
T901
H901
2006-09-18/ Ver. C
Power cables
Fixed Transmitters
0.7 H952T
0.5 U952T
1.3
Power Amplifiers
H954
U954
TD 90227GB
max load (A)
2.0
2.5
15
10
11