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Introduction
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Fig. 1.1.
The Site Controller SCM
The DPS Telecom Site Controller SCM mediates Modbus protocol traffic between Tridium JACE-545™ devices
(JACE). The Site Controller SCM converts the 9600 baud RS–232 JACE traffic to 1200 baud 202 for transport to
other Site Control Managers. Central to the Site Controller SCM design is an in-case integration of the Tridium
JACE-545™ device. In other words, the DPS Site Controller SCM and the JACE are inside a single chassis,
reducing the need for extra connectors and rack space.
Note:
the JACE-545 device is a trademark of Tridium, Inc.
The Site Controller SCM has two modes: master and slave. One master Site Controller SCM connects the JACE
Modbus interrogator to the 202 service channel. A slave Site Controller SCM links a JACE Modbus responder to
the service channel. A single Site Controller SCM master unit polls multiple Site Controller SCM slave units.
Fig. 1.2.
Example Site Controller SCM Application
Specifications
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Dimensions:
1¾"H x 17"W x 12"D (4.45 cm x 43.18 cm x 30.48 cm)
Weight:
4 lbs. 3 oz. (1.9 kg)
Mounting:
19" or 23" rack
Power Input:
–48 VDC dual feed
Current Draw:
300mA
Fuse:
½ Amp GMT
Interfaces:
1 4-pin barrier 202 port
1 DB9 craft port
Operating Temperature:
32°–140° F (0°–60° C)
Operating Humidity:
0%–95% noncondensing
