* These are Tibbo BASIC/C-programmable devices and their function depends on the loaded app.
We offer many ready-to-use apps, among them a serial-over-IP (SoI) app and Modbus Gateway app.

RS485 Modbus Sensors (Bus Probes)

Bus Probes are a family of environment sensors with an RS485 interface. The Probes communicate using standard Modbus RTU protocol.

At the moment, Tibbo offers four types of probes: the ambient temperature sensor (BP#01), ambient temperature and humidity sensor (BP#02), ambient light sensor (BP#03), and 3-axis accelerometer (BP#04).

Bus Probes are typically wired to a twisted pair cable, which distributes power and carries RS485 "+" and "-" lines. All probes accept the supply voltage in the 4V to 15V range. This allows you to power them from 5V sources (for example, the 5V output of the Tibbit #00-3), as well as standard 12V power supplies. Wide supply voltage range also means that you can allow for a significant voltage drop along the bus, i.e., use a bus cable of considerable length.

BP sensors are very compact (external dimensions only 40 x 36mm) and sport an attractive look and feel. Each sensor has two mounting holes for attaching it to walls and other surfaces.

Tibbo supplies two TPS2(G2)-compatible Tibbo BASIC applications for convenient setup and testing of Bus Probes (see BP-Tester-UI and BP-Tester-Web apps). We also offer BP-Test-Kit Test Kits that include four BP sensors (one of each kind), a TPS2L(G2) device running a preloaded BP-Tester-UI app, and a cable for connecting the Probes to the TPS2L.

Here is How You Can Use the Bus Probes

Use the Probes in your
Modbus system

Tibbo Bus Probes feature an RS485 interface and support industry-standard Modbus RTU protocol. Therefore, existing Modbus systems can use them as general-purpose environment sensors.

Note: To aid in the creation of sophisticated Modbus systems and network-enablement of serial Modbus devices, Tibbo offers Modbus Gateways.

Our Sensor Monitoring solution supports the use of Bus Probes. Connect the Probes to the RS485 port on our Sensor Hub and collect environmental data via RS485 bus.

By combining our Tibbo Project System (TPS) devices with Bus Probes you can also create your own environment monitoring systems.

Key Features

Half-duplex RS485
Modbus RTU
4-15V power

Available Probes

BP#01: Ambient temperature
BP#02: Ambient temperature
and humidity sensor
BP#03: Ambient
light sensor
BP#04: 3-axis



  • Half-duplex (two-wire) RS485 interface.
  • Communications parameters: 38400-8-N-1.
  • Modbus RTU protocol.
  • BP#01 (ambient temperature sensor):
    • Measurement range: -40 to +125°C*;
    • Measurement resolution: 0.25°C;
    • Measurement accuracy: ±1°C.
  • BP#02 (ambient temperature and humidity sensor):
    • Temperature measurement:
      • Measurement range: -25 to +50°C;
      • Measurement resolution: 0.5°C;
      • Measurement accuracy: not specified.
    • Humidity measurement:
      • Measurement range: 10 to 90%RH;
      • Measurement resolution: ±0.1%RH;
      • Measurement accuracy: ±5%RH;
      • Temp. range for valid humidity measurements: +5 to +50°C.
  • BP#03 (ambient light sensor):
    • Measurement range: 1 to 65528 lux;
    • Measurement resolution: 1 lux;
    • Measurement accuracy: 1 lux.
  • BP#04 (3-axis accelerometer):
    • Independent X, Y, and Z axes;
    • Measurement range for each axis: ±6G;
    • Measurement resolution for each axis: 0.003G;
    • Measurement accuracy for each axis: 0.1G.
  • Green and red status LEDs.
  • Power: 4 ~ 15VDC.
  • Dimensions excluding connectors (LxWxH): 40 x 36 x 19mm.
  • Operating temperature range: -40 ~ +85C.
  • Internal firmware is upgradeable through the RS485 port.
  • CE- and FCC-certified.

* The actual measurement range is limited by the operating temperature range of the Bus Probe itself, which is from -40 to +85°C.

See Also:

Files and Documentation

Probe Firmwarebp_application_firmware_v1_10.bin
DocumentationBus Probe Manual
CE Certificatebp01_02_03_04-ce.pdf
FCC Certificatebp01_02_03_04-fcc.pdf

Order BPx Bus Probes

Test kit for Bus Probes #01, #02, #03, and #04

Test kit for Bus Probes #01, #02, #03, and #04

BP#01: Ambient Temperature Sensor

BP#01: Ambient Temperature Sensor

BP#02: Ambient Temperature and Humidity Sensor

BP#02: Ambient Temperature and Humidity Sensor

BP#03: Ambient Light Sensor

BP#03: Ambient Light Sensor

BP#04: 3-axis Accelerometer

BP#04: 3-axis Accelerometer