American Dynamics Excalibur 168, Installation And Service Manual

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APPENDIX C
MP168 Matrix Switcher/Controller System
N1
N2
N3
N4
N5
N6
AWG 22 Twisted Pair Cable to
SpeedDomes, DeltaDomes and SensorNet J-
MP168 Bay (rear)
Slot N for Control
Six Position SensorNet Plug-in Connector
Figure C-1 - Rack Mounting the MP168 Bay
Network Design Considerations
A SensorNet network consists of one or more network “ links ”. Each link includes a twisted pair cable, a SensorNet host
(in this case, the MP168 Control Code Module resident in the MP168 bay), and 1 to 32 SensorNet devices (with the
MP168 Matrix Switcher/Controller system, the devices supported are SpeedDomes, DeltaDomes or SensorNet J-Boxes).
For proper operation, both ends of each
SensorNet link must be terminated. This
prevents signals reaching the end of the
line from being reflected back along the
line. All SensorNet devices have a
termination switch or jumper for this
purpose. When in the “terminate” position,
a resistor is placed across the SensorNet
cable connections to suppress reflected
signals.
On the MP168 CCM card, connectors J3
through J8 enable the user to terminate
each of the SensorNet channels (N1-N6).
To terminate a channel, place the jumper
over the two pins in the “T” position (the
two pins furthest to the right in Figure 2).
U T
J3
CH1
J4
CH2
J5
CH3
J6
CH4
J7
CH5
J8
CH6
Figure C-2 -
Jumper Pins on MP168 CCM Card
Think of each SensorNet link as a single twisted pair cable with a terminating resistor at each end. A host and up to 32
devices are then placed along the cable. If the host is placed at one end of the cable, it must be terminated, and can only
support one cable branch.
If the host is placed in any intermediate position, it is not terminated and can support 2 to 4 cable branches. In this
configuration, the last device attached to each cable branch must be terminated.
A J-Box can serve as a host repeater, to add a SensorNet link and up to 32 more devices, or to allow SensorNet cable
runs beyond 1 km (3281’).
C-2