Pelco Manual C573M-D (11/03) 11
MDA COM 1 PORT
USE NEXT
AVAILABLE
PORT
Figure 4. Connecting the MDA to a System 9760
DATA CONNECTIONSThe MDA can be connected to an external device via RS-232/422/485 standards. The
distance at which it can be installed away from another device depends on the communica-
tion type and the wire size of the cable. Maximum cable distance for RS-232 serial data for
18-24 AWG is 50 feet (15.24 m) while the maximum for RS-422 and RS-485 with 24-gauge
wire is 4,000 feet (1,219 m). For longer distances, junction boxes and heavier cable can be
used. Pelco recommends using shielded twisted pair, such as Belden 9843 or similar cable,
meeting or exceeding the basic requirements for EIA RS-422/485 applications. Decide
where the MDA will be located and follow the mounting and connection instructions.
CONNECTING THE MDA TO A SYSTEM 9740/9760CONTROLLERThe rear panel of the MDA contains two RJ-45 modular connectors for external data
communication using RS-232, RS-422, or RS-485 standards. Connect the COM 1 port on
the MDA’s rear panel to the next available RJ-45 output connector on the System 9740/9760
controller (refer to Figure 4 for an illustration of MDA connection to a System 9760 control-
ler.) The System 9740/9760 controller port to which the MDA is connected must be
programmed for proper communication with an MDA. Refer to the System CM9760-CC1
manual or to the System CM9740-CC1 manual for information about selecting and
configuring the RJ-45 ports on the System 9740/9760 controller.
Refer to Figure 37 and to Figure 38 for illustrations of connecting multiple MDA units to a
System 9760 controller.