AERCO XPC GATEWAY Communications - Manual (Page 53)

GF-122 AERCO XPC GATEWAY
53
NOTE
The Gateway Response Time for Modbus must be adjusted to 2 seconds in
order for the communication to work efficiently. This is due to the extra lag
in communications to the boiler when going through the BMS. Since the
BMS control operations take priority, it may delay the processing of a
Gateway command by a second or two depending on what it is doing at the
moment.
3.2.3 BMS Setup For Remote Setpoint Control From the XPC Gateway
For remote setpoint control of a BMS, set up the wiring connections as described in subsection 3.2. Upon
completion of all wiring connections, configure the BMS as follows:
1. Press the
FIELD ADJ key on the BMS front panel to enter the Field Adjust Mode. The yellow LED on
the key should be lit.
2. Press the
AIR TEMP key until RS232 MODE is shown on the top line of the display. If necessary,
press the ▲ or ▼ arrow key until MODBUS SLAVE appears in the second line of the display.
3. Press the
AIR TEMP key again until RS232 BAUDRATE is shown on the top line of the display.
Press the ▲ or ▼ arrow key to select a baud rate of 9600.
4. Press the
AIR TEMP key again until MODBUS ADDRESS is shown on the top line of the display.
Press the ▲ or ▼ arrow key to set the BMS address to 128.
5. Press the
FIELD ADJ key to exit the Field Adjust Mode. The yellow LED on the key should go off.
6. To set the BMS for Remote Operation, press the
CONFIG SYS key to enter the System Configuration
mode. The red LED on the key will light.
7. Press the
FIELD ADJ key until HDR SET MODE is shown in the top line of the display. Press the ▲
or ▼ arrow key to select REMOTE SET TEMP.
8. Press the CONFIG SYS key to exit the System Configuration Mode. The red LED on the key will go
off.
The BMS is now set up for Remote Setpoint control by a BAS. In the event of control signal interruption,
AERCO recommends that the
TEMP FAIL MODE setting be set to SWITCH INPUTS if you want the
BMS to continue running the boilers in the CONSTANT SET TEMP mode. In this case, ensure that the
REF TEMP is set to the desired setpoint temperature.
NOTE
Sample network diagrams showing the BMS connected to Port 2 and Port
1a of the AERCO XPC Gateway are provided in Figure 3-8. These samples
are intended for reference purposes only and do not depict all possible
network scenarios.