Bio Instruments DE-1T-485M
Phyto-Sensor dendrometer that measures micro-variations of trunk radius in micrometres over RS485.
The Bio Instruments DE-1T-485M is a Phyto-Sensor dendrometer that follows micro-variations of the trunk radius of trees and large plants in micrometres. This Modbus RTU template reads the trunk radius variation and the communication settings, and lets you change the address, baud rate and parity from ModbusCloud.
- Protocol
- Modbus RTU
- Connection
- RS485, 9600 baud
- Registers
- 5, read and write
- Brand
- Bio Instruments
- Key readings
- Trunk radius variation · Modbus address · Baud rate · Parity
- Available commands
- Modbus address · Baud rate · Parity
- Compatible models
- DE-1T-485M
- Last updated
Registers (5)
5 read, 3 write
| Name | Unit | Access | Address (Hidden until you enter your email) | Function (hidden) | Type (hidden) |
|---|---|---|---|---|---|
| Trunk Radius Variation | µm | Read | |||
| Trunk Radius Variation Float | µm | Read | |||
| Device Address | Read and write | ||||
| Baud Rate Code | Read and write | ||||
| Parity Code | Read and write |
Loading registers…
Send your device list
If a device is not in the library yet, we build the template for free as soon as we have the register data.
Use cases
- Follow the daily swelling and shrinking of a trunk on a dashboard to see how the tree responds to irrigation and weather.
- Keep 365 days of history to compare growth between seasons, trees or irrigation strategies.
- Get an email or webhook when the reading falls below a threshold you set, for example during a dry spell.
- Let automatic monitoring flag a reading that stays exactly the same for hours, for example when the rod lost contact with the trunk.
- Give each sensor its own address from ModbusCloud before you add more sensors to the same RS485 line.
Installation
Rasp rough bark over about 6 by 5 cm, drill a 3.3 to 3.5 mm hole 3 to 9 cm deep, screw in the rod and mount the sensor so the sensing rod touches the trunk.
Connect black to ground, yellow to RS485 B and white to RS485 A of the ModbusCloud Gateway, and red to a 5 to 24 Vdc supply. Terminate both ends of the bus with 120 Ω.
Give every sensor on the bus its own address with the Bio Instruments address tool or by writing Device Address. All sensors leave the factory with address 247.
In ModbusCloud, add a Modbus device with protocol RTU, the sensor address, 9600 baud and 8E1, and import this template.
Check that Trunk Radius Variation shows a value around the middle of the 0 to 10 mm range, and reposition the sensor if not.
Things to watch for
The sensor does not answer. What should I check?
Check 9600 baud, even parity, 1 stop bit and address 247 in ModbusCloud; many tools default to no parity. Swap A and B if nothing comes back, connect the black ground wire to the bus ground, and terminate both ends of the bus, because the sensor has no termination resistor inside.
The reading stays at 0 or near 10000 µm. What is wrong?
The sensing rod has reached the end of its stroke. After installation it should work around the middle of the 0 to 10 mm range. Loosen the sensor, move it on the rod until the reading is near the middle, and secure the cable to the trunk so the sensor cannot shift.
Why do I see every measured value twice?
The sensor gives each measurement as a scaled whole number and as a floating-point value. Both carry the same reading. Keep the one you want on your dashboards and remove the other from the Modbus device in ModbusCloud if you do not need it.
Can I change the address, baud rate or parity from ModbusCloud?
Yes, these three registers are writable. Writing is off per gateway by default; request it for the gateway in the portal. After a new address the sensor only answers on that address. Change baud rate or parity only when every device on the bus gets the same setting, and update the Modbus device in ModbusCloud right away.
Want to see how it works?
