American Dynamics Excalibur 168, Installation And Service Manual

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APPENDIX C
MP168 Matrix Switcher/Controller System
SensorNet Communications
With Release 3.0, the MP168 Control Code Module (CCM) supports SensorNet as well as RS-422 and AD Manchester
communications.
SensorNet is a two-wire communications protocol that provides improved data transmission speed, surge protection and
noise immunity. SensorNet is used by the MP168 system to communicate with
SpeedDomes® or DeltaDomes™ .
Connections can be made directly from the CCM to the domes, or through SensorNet J-Boxes . J-Boxes are available in
1 or 6-position models.
For new installations, AWG 22, unshielded twisted-pair cable is recommended. Maximum cable length is 1
km (3281’). Shielding adds capacitance, causing decreased signal strength as devices are attached and/or
cable length increases. When pre-existing wiring makes it necessary to use shielded twisted pair cable, the
maximum cable length is reduced. For example, Belden 8760 cable will typically support complete network
links of approximately 750 m (2500’).
SpeedDomes and DeltaDomes will operate satisfactorily at signal levels between 5v and 0.3v (peak-to-peak).
An operating range of 5v to 1v is recommended.
SensorNet Connection on the MP168 CCM
The CCM plugs into slot N in the rear of the MP168 bay. The SensorNet port is located at the top of the module,
directly beneath the yellow dot.
The SensorNet connector contains the six two-wire positions for data connections to SpeedDomes, DeltaDomes and
SensorNet J-Boxes. The six positions are labeled N1 through N6 respectively. SensorNet cables do not have a polarity
reference, so each of the two-wire cable leads can be connected to either of the two connection points for each N pair.
For appropriate pin positions on SpeedDomes, DeltaDomes and SensorNet J-Boxes, see the manual for the device used.
Attaching to SensorNet
1. Strip 6mm (.25”) of insulation from each of the SensorNet leads and insert them into the appropriate slot pairs on the
SensorNet compression connector (the pairs line up with positions N1 through N6 on the rear of the CCM).
2. Tighten the screws on each lead until they are held firmly in position. Do not over-tighten.
3. When all necessary leads are attached, plug the connector into the SensorNet port on the CCM.
C-1