CABLE SPECIFICATIONS
PLEASE ENSURE THAT THE RECOMMENDED TYPE OF CABLES ARE USED
THROUGHOUT THE INSTALLATION
The audio cables to/from the AVPSU4 unit (which is mounted in the equipment room) to
the call-point, should be a TELECOM TYPE CW1308, This cable should have a minimum
of 3 twisted pairs, and preferably 4 twisted pairs (to provide one spare pair).
DO NOT
use
any spare pair in this cable to run the DC power to the call-point.
The D.C. power output from the AVPSU4 unit feeds the required power to the call-point.
The following distance restrictions are applicable:-
Using a 1.0mm
2
, 2 core,
stranded
low Voltage cable, you may power the call-point from
the AVPSU4 (+V OUT and GROUND terminals), up to a distance of 100 metres.
Using a 2.5mm
2
, 2 core,
stranded
low Voltage cable, you may power the call-point from
the AVPSU4 (+V OUT and GROUND terminals), up to a distance of 250 metres.
If you require the call-point to be further away from the AVPSU4, or if it simply more
convenient, you may power the call-point locally using a 24 Volt DC
regulated
power
supply, which should be capable of providing a current output of up to 650mA, in which
case the power supply output should be connected to the terminals on the call-point PCB
marked “0V” and “+IN”.
The audio signal cable (CW1308 twisted pair) may be up to 1000 metres long in total.
The CALL INPUT signal (from the call-point to the AVPSU4) will normally be sent via the
3
rd
pair of the CW1308 twisted pair cable, which carries the audio signals from the call-
point to the AVPSU4. This signal is opto-isolated at both ends.
The CALL OUT signal (from the AVPSU4 to the transceiver alarm input) may be any type
of two-core cable.
Please refer to the drawing on the next page as a guide to cable connections.
DOCUMENT NUMBER AV102SS/OEM/01 REVISION 6.1 1st August 2006 Page
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