The AWAC 2 can use both RS232 and RS422 protocol for serial communication. The serial communication is handled through the 8-pin connector and the provided serial cable is compatible with both protocols. When the instrument is delivered to you it is by default set to communicate over RS232, so if you are going to communicate with it over RS422 you have to change the settings.
To change the communication protocol, connect to the instrument over Ethernet and go to the command interface in the Nortek Deployment software. The command interface can be found in the lower right corner after enabling the Advanced Mode in the Software settings.
You can check which protocol is currently enabled by using the command GETINST,RS
To change the protocol from RS232 to RS422 follow these two steps:
1) Send the command SETINST,RS=422 (similarly, if you want to change back to 232 you write RS=232 instead).
2) Send the command SAVE,INST
The command interface should now look like in the screenshot below, and you can disconnect your instrument and connect to it over RS422. Note that you have to use the provided RS422 converter. You can find more information about the commands in the Integrators Guide.
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