Bacharach AGM300 - Manual (Page 18)

10 Instruction 3015-4275
AGM300 - Connecting Communication Devices
Ammonia Display Module (ADM800) Connection
The AGM300 is connected to the ADM800 using a shielded twisted pair instrument cable. The maximum
distance between the farthest away AGM300 and ADM800 is 4500 feet.
Use any of the remaining service knockouts to gain access to the interior of the monitor. The RS-485
communication wiring between the AGM300 and ADM800 must be connected in the following manner:
Locate the RS-485 connector in the AGM300 (Page 7). Connect one lead of a twisted shielded pair to the
“B” connection point (the far left point), note the wire color. Connect the second wire to the “A” connection
point (the middle), note the wire color. Connect the ground to the “GND” connection point
Locate the RS-485 connector marked “TO MONITORS” in the ADM800 (Page 23). This connector is
located on the far-left bottom of the ADM800 PC board. Make the wire run to the ADM800 and connect the
twisted shielded pair to the RS-485 TO MONITORS connector using the same color code as used on the
AGM300.
Integrating with Building Management Systems
The AGM300 may be connected directly to a Building Management System using a shielded twisted pair cable.
The cable from the Building Management System is connected to the RS-485 connector inside the AGM300.
MODBUS RTU is the standard communication protocol.
Use any of the remaining service knockouts to gain access to the interior of the monitor. Locate the RS-485
connector and remove it from the circuit board. Secure the wire leads to the connector orienting them as shown
in the diagram below. Check to make sure that the polarity matches the wiring to the Building Management
System. When you are through securing the connections, carefully plug the connector back onto the circuit
board.
Larger Integrated Systems
You may also connect the AGM300 to a Building Management System through an ADM800. In this case, first
connect the AGM300 to the ADM800 as described above. Then, follow the instructions under the heading
ADM800 – Communications Connections on Page 26 for information on how to connect the ADM800 to a
Building Management System.
RS-485 Connector