System Sensor FAAST Modbus - Manual (Page 5)

User Guide: FAAST Fire Alarm Aspiration Sensing Technology® Modbus Protocol Schema 1
5 Rev A0
Device Sensor Status and Control Operations
Device Read
The Modbus client is able to read the device status data directly via input and holding register reads.
Device Output and Operating Mode Control
The Modbus client is able to initiate different operating modes through the Sensor Input Holding Register.
1. Write the Administrator Password in the Administrator Password holding register (this is the same as the Button
Activation Passcode configured through PipeIQ).
2. Read the Sensor API status holding register and verify that the ADMIN_UNLOCK bit is set.
3. Write the value to the Sensor Input Holding Register (40035) that initiates the desired action or mode change:
a. 0x0001 to Isolate
b. 0x0002 to Disable
c. 0x0004 to initiate Test Mode
d. 0x0008 to Silence a Fault or Alarm (when equipped with an audible indicator)
e. 0x0010 to Reset the Device
f. 0x0020 to Reset the Airflow Baseline
g. 0x0040 to Clear the Event Log
h. 0x0080 to Clear the Trend Log
i. 0x0100 to Clear the Message Log
4. Write 0x0 to the Administrator Password in the Administrator Password holding register if no further changes
are desired.
Device Configuration
In order to write a new configuration, the following steps must be followed:
1. Write the Administrator Password in the Administrator Password holding register (this is the same as the Button
Activation Passcode configured through PipeIQ).
2. Read the Sensor API status holding register and verify that the ADMIN_UNLOCK bit is set. If it is set, the Sensor API
Command Register is enabled and will process commands issued.
3. The device must be placed in Disable Mode by setting disable bit in Sensor Input Holding register Holding register.
4. Read the Operating Mode holding register.
5. The Modbus client writes the new values for the respective configuration holding registers through Write Multiple
Register Command(s).
6. Write the Save Configuration Command value, 0xAA11 in the Modbus Specific configuration Command holding register
in order to save any configuration changes.
7. The device stores new configuration.
8. Read the Modbus Specific configuration Command holding register. The value will be 0x0000 when the Command
completes successfully.
9. Remove the device from Disable Mode by clearing the disable bit Sensor Input Holding register.
10. The device will reset and the new configuration will be applied.