USER GUIDE FOR TRIAXIAL VIBRATION SENSOR - MBRTU-V3A

MBRTU-V3A-MN-EN-01 

JUN-2026

This document is applied for the following products

SKU

MBRTU-V3A

HW Ver.

1

FW Ver.

1

Item Code


 

V3A-06-485-01

Triaxial vibration sensor, RS485 Modbus RTU Output, 6KHz Ultra-low Noise MEMS sensor with Temperature, M6 screw, M12-male 4pin connector, IP67

V3A-06-485-02

Triaxial vibration sensor, RS485 Modbus RTU Output, 6KHz Ultra-low Noise MEMS sensor with Temperature, M6 screw, M12-female 4pin connector, IP67

1. Functions Change Log

HW Ver.

 

FW Ver.

Release Date

Function Change

1

1

 13 Jun 26
Initial firmware

2. Introduction

MBRTU-V3A vibration sensor is 6KHz Ultra-low Noise MEMS sensor with temperature. This sensor utilizes digital temperature sensor delivers high accuracy measurement. Output is RS485 Modbus RTU for easily integrating with any PLC, controller, SCADA, BMS or IoT gateway.

  • Digital sensor technology;
  • High accuracy;
  • Standard RS485 Modbus RTU output;
  • Plug & Play.

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3. Specification

Specification Values
Sensor Type Ultra-low noise 3-axis digital MEMS vibration sensor
Measurement axes X, Y, Z
Frequency Bandwidth 6KHz, +/- 3dB
Acceleration range +/- 16G
Sampling rate 26.667 kHz
Resolution 16 bit
Sensitivity 0.488 mg/LSB
Sensitivity tolerance ±2% typ. at 25°C
Sensitivity drift ±1% typ. over temperature
Integrated noise, 0–6.3 kHz X/Y 6 mg RMS, Z 8.7 mg RMS
Integrated noise, 0–1 kHz X/Y 2.4 mg RMS, Z 3.5 mg RMS
Surface temperature measurement -40 .. + 85 oC with +/- 0.5 oC accuracy typ. after calibration
Measurement Output 8 vibration values for each axis + surface temperature
Communication Interface RS485, ModbusRTU, baud rate of 11520 bps, none parity
Power Supply 7..36VDC max 200mA, Surge Protection for Power supply and RS485 lines
Housing Inodized Aluminium, IP67
Mounting M6x35 through-bolt, optional M5/M4 sleeve, optional magnetic adapter
Connector M12 male 4-pin, A-coded for V3A-06-485-01 and M12 female 4-pin, A-coded for V3A-06-485-02
Working temperature -40 .. + 85 oC
Dimension 46 x 42mm (without M12 connector)
Weight < 250 grams

3. Product components

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4. Dimensions

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5. Wiring

5.1 Electrical connector

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5.2 Pinout

Because the sensor uses an M12 electrical connector, please look closely at the pinouts of the M12 electrical connector as shown below.

yih8XdyIXRIVGwiO-pinout.png

A - B: RS485/ModbusRTU Output

PWR+: Power supply 7..48VDC

PWR-: Ground, 0VDC

6. Configuration

6.1 Configuration steps

  1. Connect  A pin of sensor M12 connector to RS485+ of Modbus master device (PC, PLC...) and connect  B pin of M12 connector to RS485- of Modbus master device (PC, PLC...) 
  2. Connect PWR+ and PWR- to 7-48 VDC power supply
  3. Use Modbus software to read the sensor with Modbus function of 3 and to write with Modbus function of 16. Details are in memory map registers section

6.2 Memory map registers

 

Modbus Register (Dec) Modbus Register (Hex) Func Code (Read) Func Code (Write) # Reg Description End-user Default Format Comment
0 0 3 None 2 FW_CODE V3A string Firmware code
2 2 3 None 4 FW_VERSION 1Fmmdd string Firmware version
mmdd = month / day
6 6 3 None 2 HW_VERSION 1H string Hardware version v1
8 8 3 None 2 X_VELOCITY_RMS_A   float RMS Velocity of band A, unit of mm/s, for X-axis
10 A 3 None 2 X_ACCELERATION_RMS_B   float RMS Acceleration  of band B, unit of m/s^2, for X-axis
12 C 3 None 2 X_CREST_FACTOR_B   float Crest factor of band B, for X-axis
14 E 3 None 2 X_KURTOSIS_B   float Kurtosis factor of band B, for X-axis
16 10 3 None 2 X_ACCELERATION_PEAK_C   float Peak Acceleration of band B, unit of m/s^2, for X-axis
18 12 3 None 2 X_CREST_FACTOR_C   float Crest factor of band C, for X-axis
20 14 3 None 2 X_KURTOSIS_C   float Kurtosis factor of band C, for X-axis
22 16 3 None 1 X_SHOCK_COUNT   uint16 Counter for shock events captured, a shock event is determined by exceeding shock threshold (could be config by SHOCK_THRESHOLD registers), for X-axis
23 17 3 None 1 X_TEMPERATURE_X10   int16 Temperature = TEMPERATURE_X10 divide by 10, for X-axis
24 18 3 None 2 X_SCALE_FACTOR_A   float Scale factor A for velocity and acceleration values, for X-axis
26 1A 3 None 2 X_SENSOR_SENSITIVITY   float Sensor sensitivity, unit of mV/g, for X-axis
28 1C 3 None 2 X_SHOCK_THRESHOLD   float Shock threshold to detect/count shock event, unit of G, for X-axis
30 1E 3 None 2 Y_VELOCITY_RMS_A   float RMS Velocity of band A, unit of mm/s, for Y-axis
32 20 3 None 2 Y_ACCELERATION_RMS_B   float RMS Acceleration  of band B, unit of m/s^2, for Y-axis
34 22 3 None 2 Y_CREST_FACTOR_B   float Crest factor of band B, for Y-axis
36 24 3 None 2 Y_KURTOSIS_B   float Kurtosis factor of band B, for Y-axis
38 26 3 None 2 Y_ACCELERATION_PEAK_C   float Peak Acceleration of band B, unit of m/s^2, for Y-axis
40 28 3 None 2 Y_CREST_FACTOR_C   float Crest factor of band C, for Y-axis
42 2A 3 None 2 Y_KURTOSIS_C   float Kurtosis factor of band C, for Y-axis
44 2C 3 None 1 Y_SHOCK_COUNT   uint16 Counter for shock events captured, a shock event is determined by exceeding shock threshold (could be config by SHOCK_THRESHOLD registers), for Y-axis
45 2D 3 None 1 Y_TEMPERATURE_X10   int16 Temperature = TEMPERATURE_X10 divide by 10, for Y-axis
46 2E 3 None 2 Y_SCALE_FACTOR_A   float Scale factor A for velocity and acceleration values, for Y-axis
48 30 3 None 2 Y_SENSOR_SENSITIVITY   float Sensor sensitivity, unit of mV/g, for Y-axis
50 32 3 None 2 Y_SHOCK_THRESHOLD   float Shock threshold to detect/count shock event, unit of G, for Y-axis
52 34 3 None 2 Z_VELOCITY_RMS_A   float RMS Velocity of band A, unit of mm/s, for Z-axis
54 36 3 None 2 Z_ACCELERATION_RMS_B   float RMS Acceleration  of band B, unit of m/s^2, for Z-axis
56 38 3 None 2 Z_CREST_FACTOR_B   float Crest factor of band B, for Z-axis
58 3A 3 None 2 Z_KURTOSIS_B   float Kurtosis factor of band B, for Z-axis
60 3C 3 None 2 Z_ACCELERATION_PEAK_C   float Peak Acceleration of band B, unit of m/s^2, for Z-axis
62 3E 3 None 2 Z_CREST_FACTOR_C   float Crest factor of band C, for Z-axis
64 40 3 None 2 Z_KURTOSIS_C   float Kurtosis factor of band C, for Z-axis
66 42 3 None 1 Z_SHOCK_COUNT   uint16 Counter for shock events captured, a shock event is determined by exceeding shock threshold (could be config by SHOCK_THRESHOLD registers), for Z-axis
67 43 3 None 1 Z_TEMPERATURE_X10   int16 Temperature = TEMPERATURE_X10 divide by 10, for Z-axis
68 44 3 None 2 Z_SCALE_FACTOR_A   float Scale factor A for velocity and acceleration values, for Z-axis
70 46 3 None 2 Z_SENSOR_SENSITIVITY   float Sensor sensitivity, unit of mV/g, for Z-axis
72 48 3 None 2 Z_SHOCK_THRESHOLD   float Shock threshold to detect/count shock event, unit of G, for Z-axis
74 4A 3 None 1 DEBUG_I2C_ERROR   hex I2C read error code.
0: No error. 1: Error.
75 4B 3 None 196 spare   hex spare
271 10F 3 16 2 X_CONFIG_SCALE_FACTOR_A   float Configuration of SCALE_FACTOR_A, for X-axis
273 111 3 16 2 X_CONFIG_SENSOR_SENSITIVITY   float Configuration of sensor sensitivity, unit of mV/g, for X-axis
275 113 3 16 2 X_CONFIG_SHOCK_THRESHOLD   float Configuration of shock threshold to detect/count shock event, unit of G, for X-axis
277 115 3 16 2 Y_CONFIG_SCALE_FACTOR_A   float Configuration of SCALE_FACTOR_A, for Y-axis
279 117 3 16 2 Y_CONFIG_SENSOR_SENSITIVITY   float Configuration of sensor sensitivity, unit of mV/g, for Y-axis
281 119 3 16 2 Y_CONFIG_SHOCK_THRESHOLD   float Configuration of shock threshold to detect/count shock event, unit of G, for Y-axis
283 11B 3 16 2 Z_CONFIG_SCALE_FACTOR_A   float Configuration of SCALE_FACTOR_A, for Z-axis
285 11D 3 16 2 Z_CONFIG_SENSOR_SENSITIVITY   float Configuration of sensor sensitivity, unit of mV/g, for Z-axis
287 11F 3 16 2 Z_CONFIG_SHOCK_THRESHOLD   float Configuration of shock threshold to detect/count shock event, unit of G, for Z-axis

7. Installation

  • Create a hole on the installation surface with depth >= 6mm and thread M6x1.0
  • Install the sensor to the hole using provided bolt
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8. Calibration

The delivered sensor should be factory-calibrated. If customer would like to re-calibrate, please follow below process

8.1 Calibration preparation

  • V3A sensor
  • Axis Y/ Z calibration support fixture. 
  • A vibration calibrator with an M6 threaded mounting slot, capable of delivering standard 10 mm/s velocity RMS at 80Hz under a minimum 500g load. 
  • Modbus/RS485 to USB cable
  • 7-48 VDC power supply
  • Modbus Master Log software/application
  • PC

8.2 Calibration setup

  1. Connect sensor's RS485 port to the PC
  2. Connect PWR+, PWR- to 7-48VDC power supply
  3. Open Modbus Master Log software/application on PC
  4. Configure the baud rate of 115200 bps, parity of none for the software/application for Modbus communication
  5. Configure parameters to read are X_SENSOR_SENSITIVITY, X_VELOCITY_RMS_A, Y_SENSOR_SENSITIVITY, Y_VELOCITY_RMS_A, Z_SENSOR_SENSITIVITY, Z_VELOCITY_RMS_A with Modbus function of 3

8.3 X/Y/Z axis calibration

8.3.1 X axis calibration

  1. Install the sensor to the vibration calibrator with provided bolt
  2. Set the vibration calibrator to output a steady reference signal of 80Hz at standard 10 mm/s velocity RMS.  
  3. Log about 30 values of X_VELOCITY_RMS_A parameters
  4. Calculate the average value of X_VELOCITY_RMS_A
  5. Calculate X_CONFIG_SENSOR_SENSITIVITY = X_SENSOR_SENSITIVITY * standard RMS velocity (10 mm/s) / (average value of X_VELOCITY_RMS_A in step 4). 
  6. Write calculated X_CONFIG_SENSOR_SENSITIVITY to the sensor with Modbus function of 16
  7. Re-read the X_VELOCITY_RMS_A parameters. The value should be standard RMS velocity (10 mm/s)
  8. Power off the vibration calibrator and unmount the sensor from the calibrator.  

8.3.2 Y axis calibration

  1. Secure the sensor onto the Axis Y/Z calibration support fixture then bolt the entire assembly back onto the calibrator on the target Y axis
  2. Set the vibration calibrator to output a steady reference signal of 80Hz at standard 10 mm/s velocity RMS.  
  3. Log about 30 values of Y_VELOCITY_RMS_A parameters
  4. Calculate the average value of Y_VELOCITY_RMS_A
  5. Calculate Y_CONFIG_SENSOR_SENSITIVITY = Y_SENSOR_SENSITIVITY * standard RMS velocity (10 mm/s) / (average value of Y_VELOCITY_RMS_A in step 4). 
  6. Write calculated Y_CONFIG_SENSOR_SENSITIVITY to the sensor with Modbus function of 16
  7. Re-read the Y_VELOCITY_RMS_A parameters. The value should be standard RMS velocity (10 mm/s)
  8. Power off the vibration calibrator and unmount the sensor from the calibrator.  

8.3.3 Z axis calibration

  1. Secure the sensor onto the Axis Y/Z calibration support fixture then bolt the entire assembly back onto the calibrator on the target Z axis
  2. Set the vibration calibrator to output a steady reference signal of 80Hz at standard 10 mm/s velocity RMS.  
  3. Log about 30 values of Z_VELOCITY_RMS_A parameters
  4. Calculate the average value of Z_VELOCITY_RMS_A
  5. Calculate Z_CONFIG_SENSOR_SENSITIVITY = Z_SENSOR_SENSITIVITY * standard RMS velocity (10 mm/s) / (average value of Z_VELOCITY_RMS_A in step 4). 
  6. Write calculated Z_CONFIG_SENSOR_SENSITIVITY to the sensor with Modbus function of 16
  7. Re-read the Z_VELOCITY_RMS_A parameters. The value should be standard RMS velocity (10 mm/s)
  8. Power off the vibration calibrator and unmount the sensor from the calibrator.  

9. Support contacts

Manufacturer

Daviteq Technologies Inc

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No.11 Street 2G, Nam Hung Vuong Res., An Lac Ward, Binh Tan Dist., Ho Chi Minh City, Vietnam.
Tel: +84-28-6268.2523/4 (ext.122)

Email: support@daviteq.com | https://www.iot.daviteq.com/

 

Revision #9
Created Wed, Jun 17, 2026 4:20 AM by Phan Van Luc
Updated Wed, Jun 17, 2026 11:27 AM by Phan Van Luc