BW SENSING BWM427 User manual

BWM427 Serials
Modbus Dual-Axis Incli
nometer
Technical Manual

BWM 427
Modbus Dual-Axis Inclinometer
●Dual-axis inclination measurement
●Resolution: 0.001°
●Product size: L90*W40.5*H26(mm)
●Voltage input: 9~35V
●Max accuracy: 0.01°
●Measuring range: ±90°
●IP67 protection
●Communication: RS232/485/TTL optional
●Industrial automatic leveling
●Medical devices
●The solar automatic tracking system
●Tower tilt monitoring
●Hoisting angle control
●Structural deformation monitoring
●Measuring and mapping instrument
●Military equipment automation
Introduction
Features
Applications
Designed by BWSENSING, BWM427 is a cost-effective dual-axis inclinometer with MEMS technology
and digital output. It has a measuring range of ± 90° and a full-scale accuracy of 0.01° and a
operating temperature of -40℃~+85℃. The product uses a high-accuracy MEMS accelerometer and
a high-resolution differential digital-to-analog converter with built-in automatic compensation and
filtering algorithms to reduce errors caused by environmental changes. It measures the change of
static gravitational field and converts it into angle change. The change directly outputs the horizontal
angle value through digital mode. It has high long-term stability, small temperature drift, simple use
and strong resistance to external interference. It apply to military equipment, industrial automation,
surveying and mapping, etc.
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

Specifications
BWM 427
Modbus Dual-Axis Inclinometer
Resolution: The measured minimum change value that the sensor can detect and resolve within
the measurement range.
Accuracy: The error between the actual angle and the Root mean square(RMS) of the measured
angle of the sensor (≥16 times).
Electrical Specifications
Parameters
Power supply(DC)
Operating current
Operating temperature
Store temperature
Conditions
Non-loaded
Min
9
20
-40
-55
Typical
12
30
Max
35
40
+85
+100
Units
V
mA
℃
℃
Performance Specifications
25
25
2000g,0.5ms,3times/axis
150g(Excludes box)
Conditions
Indoor
BWM427-90
±90
X-Y
0.01
0.001
±0.005
100
according to GBT17626
≥100 MΩ
≥100000hs
°
°
°/℃
Hz
Units
°
Measuring range
Measuring axis
Accuracy
Resolution
Frequency response
Electromagnetic
compatibility
Insulation resistance
Shock resistance
N.W.
Zero temperature
drift
MTBF
Parameters
Max
-40~+85℃
Cross axis error 25℃0.01°
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]-801

孔Φ 2.1mm
30
41
47
36
78
29
40.5
4
11 26
4.5 通孔
Mechanical Characteristic
Package size
Product Size: L90*W40.5*H26（mm）
BWM 427
Modbus Dual-Axis Inclinometer
Connector
Protection level
Shell material
Installation
Metal connector（standard cable is 1.5m）
IP67
Magnesium alloy anodizing
Four M4 screws
90
Bare plate product size
Product size: L47*W36*H15(mm)
Note: ±1mm error for length and width dimensions, please refer to actual size.
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

BWM 427
Modbus Dual-Axis Inclinometer
Installation direction
The correct installation method can avoid measurement error. The following points should be made
when installing the sensor:
First of all, to ensure that the sensor mounting surface and the measured surface completely close,
the measured surface should be as horizontal as possible, can not have the angle shown in Figure A
and Figure C, the correct installation is shown in Figure B and Figure D.
the measured surface
uneven surface
generates the
angle
the measured surface
C D
AB
the measured surface the measured surface
Secondly, the bottom cable of the sensor and the axis of the measured object shouldn't generate
the angle shown in E. When installing, the bottom cable of the sensor should be kept parallel or
orthogonal to the rotation axis of the measured object. This product can be installed horizontally
or vertically (vertical installation requires customization). The correct installation method is shown in
Figure F.
Finally, the installation surface of the sensor must be fixed with the measured surface tightly and
smoothly, to avoid measurement error that may be caused by the acceleration and vibration.
uneven surface
generates the
angle
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

RED
1
VCC
DC 9-35V
BLUE
2
NC
BLACK
3
GND
GREEN
4
RXD
（B、D-）
YELLOW
5
TXD
（A、D+）
Sensor
RED VCC DC9-35V
485+
485-
BLACK GND
RS 485 wiring diagram
GND
1
3
4
5
GREEN D-
1
3
4
5
GND
DC9-35V
1
5
4
2
3
6
7
8
9
BLACK GND
YELLOW TXD
RED VCC
GREEN RXD
RS 232 wiring diagram
Electrical connectionss
Electrical interfaces
Cable color
&
Function
Inclinometer
Inclinometer
Signal 66
22
acquisition
end
YELLOW D+
BWM 427
Modbus Dual-Axis Inclinometer
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

BWM 427
Modbus Dual-Axis Inclinometer
Debug software
Users can directly download serial assistant on official website (Supports-Download). You can also
use more convenient and intuitive PC software.
BWM427 supporting serial debugging software can be connected to the inclinometer on the
computer for angle display. The software debugging interface is as shown in the figure below. Using
the debug software, it can conveniently display the current X/Y direction tilt angle, and you can also
modify and set other parameters by yourself.
①
②
③
Correctly connect the inclinometer serial port hardware and connect the power supply.
Select the computer serial port and baud rate and click connect Serial Port.
Click Start and the tilt angle of the tilter in the X /Y direction will be displayed on the
Software use steps:
Note you can switch to Chinese or English version by the Upper right button
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

1 Data Frame Format： （8 data bits, 1 stop bit, non verification, default rate 9600）
Address
Code
（1byte）
0x01
Function
Code
（1byte）
0x03（read）
0x06（write）
The first low
address
register
（1byte）
xx xx
xx
xx xxxx
Data format: Hexadecimal
Address code: Default 01 (note: it should not exceed FF)
Function Code: 03 represents reading register,06 represents presetting register.
Register Address: the starting address the register need to be operated
Register amount: the amount need to operate
Checksum: it is calculated by the host. (We recommend that users need to use the CRC calculation software.)
X-axis Angle: Register 00 01
Y-axis Angle: Register 00 02
Product Address: Register 00 03
Zero Type: Register 00 04
The first high
address
register
（1byte）
High
register
number
（1byte）
Low register
number
（1byte）
Checksum
(2byte）
2 Command Format：
2.1 Read angle of X-axis Command: 01 03 00 01 00 01 D5 CA
0x00 0x01 0xD5CA
0x01 0x03
Command response:
Note: The data field is a hexadecimal number (PLC or configuration software reads the data directly with a 16-bit
register is decimal). After converting to decimal, the real data = (data field -10000)/100. If the data field is 3D52, it
is converted to decimal 15698, real data = (15698-10000)/100 = 56.98 degrees; the data field is 1230, converted
into decimal 4656, real data = (4656-20000)/100 = -53.44 degree.
0x00 0x01
Address
Code
（1byte）
Function
Code
（1byte）
The first low
address
register
（1byte）
The first high
address
register
（1byte）
High
register
number
（1byte）
Low register
number
（1byte）
Checksum
(2byte）
xx xxxx
0x01 0x03 0x02 xx
Address
Code
（1byte）
Function
Code
（1byte）
High
number
（1byte）
Number of
bytes
（1byte）
Low
number
（1byte）
Wrong CRC
checksum
(2byte）
BWM 427
Modbus Dual-Axis Inclinometer
Protocol
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

2.3 Read angle of both X-axis and Y-axis Command: 01 03 00 01 00 02 95 CB
0x01 0x03
X axis Angle
（2byte）
Y axis Angle
（2byte）
0x04 xx xxxxxx
xx xx
2.2 Read angle of Y-axis Command: 01 03 00 02 00 01 25 CA
0x00 0x01
0x01 0x03
Command response:
0x00 0x02
Address
Code
（1byte）
Function
Code
（1byte）
The first low
address
register
（1byte）
The first high
address
register
（1byte）
High
register
number
（1byte）
Low register
number
（1byte）
Checksum
(2byte）
xx xxxx
0x01 0x03 0x02 xx
Address
Code
（1byte）
Function
Code
（1byte） （1byte）
Number of
bytes
（1byte） （1byte）
Checksum
(2byte）
xxxx
0x00
0x01
0x01 0x03 0x00 0x02
Address
Code
（1byte）
Function
Code
（1byte）
The first low
address
register
（1byte）
The first high
address
register
（1byte）
High
register
number
（1byte）
Low register
number
（1byte）
Checksum
(2byte）
xxxx
Address
Code
（1byte）
Function
Code
（1byte）
Number of
bytes
（1byte）
Checksum
(2byte）
Command response:
2.4 Set communication rate Command: 01 06 00 0B 00 02 79 C9
Command response:
Note: 0000 represents 2400; 0001 represents 4800; 0002 represents 9600; 0003represents 19200.
0x0002 0x79C9
0x01
Address Code
(1byte)
Function Code
(1byte)
The high address
register (1byte)
The low address
register (1byte)
Data field
(2byte)
Checksum
(2byte)
0x0B
0x06 0x00
0x0002 0x79C9
0x01
Address Code
(1byte)
Function Code
(1byte)
The high address
register (1byte)
The low address
register (1byte)
Data field
(2byte)
Checksum
(2byte)
0x0B
0x06 0x00
The default is 0002:9600.
BWM 427
Modbus Dual-Axis Inclinometer
Data field
high
Data field
low
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]

Command response:
Address Code
(1byte)
0x01
Function Code
(1byte)
The high address
register (1byte)
The low address
register (1byte) Data field
(2byte)
Checksum
(2byte)
0x0A
0000:
absolute zero
0001:
relative zero
Command:01 06 00 0A 00 00 A9 C8
2.5 Set relative/absolute zero
0x06 0x00
Address Code
(1byte)
0x01
Function Code
(1byte)
The first high
address register
(1byte)
The first low
address register
(1byte)
Data field
(2byte)
Checksum
(2byte)
0x0A
0000:
absolute zero
0001:
relative zero
0x06 0x00
Note: absolute zero：Based on the factory-calibrated zero point.
relative zero: Reference to the zero after the current installation.
0xA9 C8
0xA9 C8
2.6 Query relative/absolute zero Command: 01 03 00 04 00 01 C5 CB
Command response:
0x01
xx0x03 0x02 xx xxxx
0x00 0x01 0xC5CB
0x01 0x03 0x00 0x04
Address
Code
（1byte）
Function
Code
（1byte）
The first low
address
register
（1byte）
The first high
address
register
（1byte）
High
register
number
（1byte）
Low register
number
（1byte）
Checksum
(2byte）
Address Code
(1byte)
Function Code
(1byte)
Number of
bytes（1byte）
High number
（1byte）
Low
number
（1byte）
Wrong CRC
checksum
（2byte）
Command response:
2.7 Set module address Command: 01 06 00 0D 00 03 58 08
Module
address
Address Code
(1byte)
0x01
Function Code
(1byte)
The high address
register (1byte)
The low address
register (1byte)
Data field
(2byte)
Checksum
(2byte)
0x0D
0x06 0x00 xx xx
Module
address
Address Code
(1byte)
Function Code
(1byte)
The high address
register (1byte)
The low address
register (1byte)
Data field
(2byte)
Checksum
(2byte)
0x0D
0x06 0x00 xx xx
Module
address
BWM 427
Modbus Dual-Axis Inclinometer
Bewis Sensing Technology LLC
www.bwsensing.com Tel: [phone]