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CCTV Visual Flame Detector - Technical Manual
Ref: 2200.5000
4.1.6
Page 21 of 48
Rev: 6.0
RS485 Communications
The RS485 twisted pair cable is connected to the detector RS485-A signal on terminal 5 and the
RS485-B signal on terminal 6. It is possible to multi-drop more than one detector using twisted pair
cabling, refer to the following sections. The RS485 line termination link J2 an J3 for channels A & B
respectively, located on the detector baseboard, should be fitted if the detector is either the last
detector of a multi-drop loop or where only one detector is fitted. Each detector represents one RS485
unit load. A maximum of 32 devices, either detectors or other RS485 compatible equipment, can be
connected to a single transmission line.
4.1.7
Video (twisted pair)
The video twisted pair cable is connected to the detector +Video signal on terminal 9 and the
-Video signal on terminal 10. It is possible to multi-drop more than one detector using twisted pair
video cabling for details refer to the following sections. The video line termination link J4, located on
the detector baseboard, should be fitted if the detector is either the last detector of a multi-drop loop or
where only one detector is fitted. A maximum of 6 detectors can be connected in a multi-drop loop.
4.1.8
Video (Coaxial)
The video coaxial cable is connected to the detector +Video signal on terminal 9 (coax conductor) and
the Video ground on terminal 11 (coax screen). Care should be taken when connecting to commercial
video equipment as the Video ground is often connected to the equipment 0V or earth. This can result
in the detector supply current returning through the coaxial cable screen, which may affect the video
quality. In such cases the detector supply cables should be increased in size to reduce cable volt drop
to a minimum. The video line termination link J4 should not be fitted. It is not possible to multi-drop
more than one detector using coaxial video cabling.
This document is strictly private and confidential, reproduction without Micropack approval is prohibited. © Micropack Engineering Ltd, 2000