Armstrong AGE4, Installation And Operating Instructions Manual

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Up to 32 single load devices can be connected to one RS-485 system without using a repeater. As this
module is a 1/8 load device, up to 256 modules can be connected to the bus. Repeaters can be used to
extend the maximum transmission distance and increase device count if needed.
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A screened, twisted-pair cable should be used. The cable screen should be connected to the COM
terminal and connected to safety ground at one point.
NOTE
: In some cases, better performance is achieved if no COM connection is made. Device can operate with 2
wire connection.
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The pump contains neither termination nor bias circuitry. RS-485 wiring should be externally terminated
if needed. For short wiring and/or low baud rate, interface can operate without termination. However,
it is recommended that termination (100-150 ohm resistor) is added on both ends of bus wiring. There
are wiring length limits regarding to speed and termination:
NOTE: Any branch/derivative cable is considered unterminated. Keep them short, below 250m combined for
maximum speed and reliability.
5.6.4 SERIAL COMMUNICATION DEFAULT SETTING (SPEED, PARITY AND ADDRESS)
MODBUS RTU: By default, each device is set to 19200-E-1 (even parity), address 245. Setup the registers to
configure each device before connecting it to existing network. Othwerise you can power each device one by
one, configuring the settings before adding another one.
BACNET MST/TP: By default, each device is set to 38400 baud, MAC 1. Use web interface to modify configuration.
5.8 BMS COMMUNICATION OVER MODBUS
5.7.1 MODBUS RTU OVER RS-485
AGE4 pump is a Modbus RTU slave. Typically, only one master device is connected to the serial bus, and one or
several slaves are also connected to the bus.
5.7.2 MODBUS OVER ETHERNET
Modbus device is available at port 502. Default address is thus 192.168.0.245:502. Supported protocols are
Modbus TCP, Modbus RTU over TCP, Modbus UDP and Modbus RTU over UDP. The protocol is automatically
recognized according to received packet and no additional configuration is needed.
NOTE: Device ID equals slave address. Controller requests must match this value [245 by default].