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A2C-SG2-M12 

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9.1.1

 

Command: Setup ADC 

The global minimum, maximum and mean values are continuously updated. They can be set to the current value i.e. reset by 
sending the following message: 

Command 

Sub Command 

Data[0] 

Data[1] 

Data[2] 

Data[3] 

Data[4] 

Data[5] 

0x40 

Channels 

Polarity 

Gain 

Data Rate 
Filter MSB 

Data Rate 
Filter LSB 

Chop 
Enabled 

Buffer 
Enabled 

DLC = 0x08  

 

Channels: 

 

0x01 = Use only channel 1 

 

0x02 = Use only channel 2 

 

0x03 = Use both channel 1 & 2 

 

Polarity: 

 

0x00 = Bipolar inputs (default for strain gauge bridges) 

 

0x01 = Unipolar inputs 

 

Gain: 

 

0x01 = Analogue amplifier gain = 1 

 

0x08 = Analogue amplifier gain = 8 

 

0x10 = Analogue amplifier gain = 16 

 

0x20 = Analogue amplifier gain = 32 

 

0x40 = Analogue amplifier gain = 64 

 

0x80 = Analogue amplifier gain = 128 (recommended for strain gauge bridges) 

 

Data Rate Filter: 

Determines the digital filter and thereby the data rate of the A2C-SG. The lower the value the higher the data rate 

and consequently higher noise. When chopping is disabled, a data rate value of 1 in single channel mode will give an output rate of 
4700 samples per second. In dual channel mode this falls to 437 samples per second for each channel. A value of 10 results in 533 
and 52 samples per second respectfully.  

 

0x0001 - 0x03FF. 

 

Chop Enabled: 

chopping is a way to almost eliminate offset voltage errors on the expense of lower data rate. It also improves the 

RMS noise, as part of the chopping is done by averaging. For a single channel measurement and a data rate value of 96, the sample 
frequency becomes 12.5Hz, compared to 50Hz without chopping enabled.  

 

0x00 = chopping disabled 

 

0x01 = chopping enabled 

 
Buffer Enabled: 

If enabled, the input channel feeds into a high impedance input stage of the buffer amplifier. Therefore, the input 

can tolerate significant source impedances and is tailored for direct connection to external resistive-type sensors such as strain 
gauges or resistance temperature detectors (RTDs). 

 

0x00 = buffer disabled 

 

0x01 = buffer enabled 

 
 

 

 

Summary of Contents for A2C-SG2-M12

Page 1: ...Durable aluminum stainless steel housing Software upgradable via CAN bus Signal to noise ratio calculation General Description The A2C SG2 M12 Strain gauge amplifier uses state of the art digital and analogue components to achieve exceptional sensitivity and high band width Specifications Selectable 2 5V 5V Strain gauge supply 11 30V supply voltage 70mA supply current CAN interface 2 0A B CAN driv...

Page 2: ...2 M12 A Black anodized aluminum M12 5pin Male connector for CAN Bus 2 x M12 5pin Female for strain gauges Yes No A2C SG2 M12 S Stainless steel 316 M12 5pin Male connector for CAN Bus 2 x M12 5pin Female for strain gauges Yes No For a customer specific package please contact us We have other materials coatings available not listed here ...

Page 3: ...Page 3 of 44 Dual strain gauge amplifier with CAN bus Specifications for A2C SG2 M12 Dual strain gauge amplifier to CAN bus Version 1 11 30 07 2021 ...

Page 4: ...ded periodic messages follow ADC Released for public viewing Added Integer Scalling section Corrected CAN follow ADC wrong values for ints and floats New commands for periodic messages from firmware 0x0107 and onwards New examples Corrected wrong value to reset factory settings Added more examples of float to byte array for calibration Added data to specifications Corrected float to array error Gr...

Page 5: ...Command Get Standard CAN ID 17 7 2 Baud rate 17 7 2 1 Command Set baud rate 17 7 2 2 Command Get baud rate 18 7 3 Custom baud rate 18 7 3 1 Command Set custom baud rate 18 7 3 2 Command Get custom baud rate 19 7 4 CAN Filters 19 7 4 1 Command Set CAN Filters 19 7 4 2 Command Get CAN Filters 20 8 ADC setup 21 8 1 Bipolar Unipoloar configuration 21 9 From Measurement to CAN value 22 9 1 1 Command Se...

Page 6: ...ADC 34 13 2 J1939 type CAN Messages only for 2 active channels 34 13 2 1 Command Set Periodic Messages to follow ADC J1939 style 34 13 2 2 Command Get Periodic Messages to follow ADC J1939 style 35 14 Signal to Noise calculations 35 14 1 1 Command Set SNR sample numbers 35 15 Calibrating 36 15 1 1 Command Calibrate input channels using floating point data 36 15 1 2 Command Calibrate input channels...

Page 7: ...m Collector Emitter Voltage Maximum continuous current 40 75 V mA CAN BUS 2 0A B Transceiver delay loop time Baud rate Default device standard ID Default device filters Software Protocol Hardware Protocol 10 0x125 0x3E8 0x3EB Proprietary 2 0A 2 0B 150 1000 ns kBits sec HOUSING Housing Body Material A suffix Housing Body Material S suffix Lid Material A suffix Lid Material S suffix Black anodized A...

Page 8: ...A2C SG2 M12 WWW LILLIESYSTEMS COM 8 of 44 2 1 Functional block diagram ...

Page 9: ...0 490 1 4800 0 625 442 000 55 000 28 000 14 000 7000 3450 2 2 2 Effective resolution Data Rate Filter value Output data rate Hz Settling time ms Gain 1 Gain 8 Gain 16 Gain 32 Gain 64 Gain 128 1023 4 7 639 4 24 24 24 24 24 23 640 7 5 400 24 24 24 24 23 5 22 5 480 10 300 24 24 24 24 23 5 22 5 96 50 60 23 5 23 23 22 5 22 21 5 80 60 50 23 23 22 5 22 5 22 21 32 150 20 22 5 22 5 22 22 21 5 20 5 16 300 1...

Page 10: ... of 44 2 4 Strain gauge pin outs Please refer to the marking on the A2C SG2 for how to connect it 3 Mechanical Drawing 3 1 Mounting Mount the sensor on an even surface Use up to 4x M4 bolts to secure the sensor from the top or the bottom ...

Page 11: ...hese tools are essential No understanding of CAN bus and programming is required The U2C is the programming tool which connects to the USB port of a windows PC in one end and the sensor CAN bus on the other end The U2C also functions as a general USB to CAN Bus adaptor bus monitor Figure 1 U2C Programming tool The window GUI enables the user to easily set most parameters in the amplifier and in re...

Page 12: ...lease go to www lilliesystems com u2c or click here If you have already installed the A2C Sensor Utility software then this will update itself after being restarted If you do not get any updates please make sure that you have internet access and that you restart the program 2 times Connect the A2C to the T connector Connect the power supply through the M12 connector which also contains a 120Ohm te...

Page 13: ...ty program Figure 5 ADC setup To change a value first change the value followed by pressing the Set Sensor Parameters button All the values changed will be sent to the A2C SG To save the values so that the A2C SG uses the values at start up press the Program Sensor button If this button is not press the A2C SG will use the previously saved values after a restart power cycle To view real time measu...

Page 14: ...ange the update interval Tools Options General A value of 100ms or 50ms is suitable but lower values are possible if the PC is powerful enough To view a graph of the data press the Ch 0 or Ch 1 check boxes followed by the Show Graph button The values displayed are the normal values Figure 7 shows example data from a load cell being compressed and tensioned by hand ...

Page 15: ...ings on the left pane to open up the settings for the U2C 2 Disable periodic messages a Go to the Periodic Messages tab and disable all tasks b Press the Set Sensor Parameters this will disable standard periodic messages c Click the radio button Standard send Normal value only d Unselect the check boxes Enable channel 1 and Enable channel 2 e Click Update A2C SG 3 Press the Get Sensor Parameters a...

Page 16: ...TR DLC Command Sub command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 Bit length 1 4 8 8 8 8 8 8 8 8 Range 0 Always 0 1 8 0x00 0xff 0x00 0xff 0x00 0xff 0x00 0xff 0x00 0xff 0x00 0xff 0x00 0xff 0x00 0xff Identifier Default Identifier is set to 0x125 from factory but can be changed as shown in 7 1 1 RTR RTR is not used so it must always be 0 DLC DLC should be between 1 and 8 There is always at least o...

Page 17: ... are not used Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xE8 STD_EXT ID MSB ID ID ID LSB DLC 0x06 The reply format follows the same format as setting the CAN ID as seen in 7 1 1 7 2 Baud rate The Baud rate is the communication speed on the CAN bus It can be set to predefined values or to a custom value The maximum CAN bus cable length is dependent on the baud rate In gene...

Page 18: ...1 36 10 𝐵𝑎𝑢𝑑 𝑟𝑎𝑡𝑒 𝑃𝑅𝐸𝑆 𝑩𝑺𝟏 𝑇1 𝑆𝑎𝑚𝑝𝑙𝑒 𝑃𝑜𝑖𝑛𝑡 1 𝑚𝑢𝑠𝑡 𝑏𝑒 𝑙𝑒𝑠𝑠 𝑡ℎ𝑎𝑛 16 𝑩𝑺𝟐 𝑇1 𝐵𝑆1 1 𝑚𝑢𝑠𝑡 𝑏𝑒 𝑙𝑒𝑠𝑠 𝑡ℎ𝑎𝑛 8 Example Generate baud rate of 62 5kbits second We first select a prescale PRES value that creates an even T1 number 36 is selected The sample point is chosen to be 75 36 10 62500 32 16 𝑇1 16 0 75 1 11 𝐵𝑆1 𝑠𝑎𝑡𝑖𝑠𝑓𝑦 𝑎 𝑣𝑎𝑙𝑢𝑒 𝑙𝑒𝑠𝑠 𝑡ℎ𝑎𝑛 16 𝑜𝑘 16 11 1 4 𝐵𝑆2 𝑠𝑎𝑡𝑖𝑠𝑓𝑦 𝑎 𝑣𝑎𝑙𝑢𝑒 𝑙𝑒𝑠𝑠 𝑡ℎ𝑎𝑛 8 𝑜𝑘 7 3 1 Command Set c...

Page 19: ...ded filters which are unsigned 32 bit integers and used for 29bit identifiers There are 4 standard filters and 2 extended filters The standard filters only allow a message with the same ID as the filter value to pass through From the factory settings the filters are configured as follows Standard Filter 1 1000 Standard Filter 2 1001 Standard Filter 3 1002 Standard Filter 4 1003 Extended Filter 1 0...

Page 20: ...03 0x01 0x02 0x03 0x04 DLC 0x06 7 4 2 Command Get CAN Filters To get the current sensor filter settings send the following CAN message Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xE9 FILT DLC 0x02 values above 2 are also valid but Data bytes are not used FILT Filter Number 0x01 Get Standard Filter 1 2 0x02 Get Standard Filter 3 4 0x03 Get Extended Filter 1 0x04 Get Extended Filt...

Page 21: ...e A2C SG still maintaining excellent noise performance For example when the gain is set to 128 the rms noise is 8 5 nV typically when the output data rate is 4 7 Hz This is equivalent to 23 bits of effective resolution or 20 5 bits of noise free resolution The A2C SG can be programmed to have a gain of 1 8 16 32 64 and 128 Therefore the bipolar input voltage ranges are from 19 53 mV to 2 5 V with ...

Page 22: ...e ADC inputs are shorted 0 input voltage the ADC output is half the ADC range 0x80000 A negative differential voltage will result in values between 0 0x7FFFFF and positive voltages between 0x80000 0xFFFFFF After sampling the calibration constants are applied From the factory the result is calibrated in such a way that the minimum ADC input results in 100 and maximum input 100 This is useful in str...

Page 23: ... The lower the value the higher the data rate and consequently higher noise When chopping is disabled a data rate value of 1 in single channel mode will give an output rate of 4700 samples per second In dual channel mode this falls to 437 samples per second for each channel A value of 10 results in 533 and 52 samples per second respectfully 0x0001 0x03FF Chop Enabled chopping is a way to almost el...

Page 24: ...28 0x02 0x5D 0x01 chop enabled 0x01 buffer enabled DLC 0x08 9 1 2 Get ADC mode To get the current ADC mode this command can be sent Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xC0 DLC 0x01 Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x0C Channels Polarity Gain Data Rate MSB Data Rate LSB Chop Enabled Buffer Enabled DLC 0x08 The format follows the same as ...

Page 25: ... 4 Data 5 0x41 Voltage DLC 0x02 Voltage 0x00 Use 5V excitation 0x01 Use 2 5V excitation 0x02 Turns off Excitation voltage This is useful for measuring the SN ratio 10 1 2 Get excitation voltage Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xC6 DLC 0x01 Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xC6 Voltage DLC 0x02 The format follows the same as for sendi...

Page 26: ... 2 b numTaps 1 x n numTaps 1 The coefficients points to a coefficient array of size numTaps Coefficients are stored in time reversed order b numTaps 1 b numTaps 2 b N 2 b 1 b 0 11 1 1 Command Set FIR parameters Send this command Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x44 Channel EN TAPS DLC 0x04 values above 0x04 are also valid but Data bytes are not used Channel is the cha...

Page 27: ...C 0x08 11 1 3 Command Get FIR parameters Send this command Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xD4 Channel DLC 0x02 values above 0x02 are also valid but Data bytes are not used Channel is the channel number that is requested and must be one of the following values 0x00 channel 1 0x01 channel 2 Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xD4 Chann...

Page 28: ...the checkbox to enable the FIR filter Press the Send setup parameters to sensor For the A2C SG2 to load the filter values at startup they must be saved first Press the Save Filter 1 and Save Filter 2 to save the values to the memory respectively for filter 1 2 11 3 Using MATLAB In MATLAB a FIR filter can be designed with the fir1 function h fir1 28 6 24 The first argument is the filter order which...

Page 29: ...ly synced value Please see the Sync command in section 0x02 Get the minimum values 0x03 Get the maximum values 0x04 Get the mean values 0x05 Get the RMS values 0x06 Get the previously synced RMS values 0x10 After the 0x0A and a sub command have been received the sensor will return the measurements for both channels as two 24bit signed integers The RET value applies to both channels at the same tim...

Page 30: ... from channel 1 0x03 Divide channel 2 with channel 1 0x04 Multiply channel 1 with channel 2 0x05 Subtract channel 1 from channel 2 0x06 Divide channel 1 with channel 2 Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x0C Return type Value type MATH Math Result MSB Math Result Math Result Math Result LSB DLC 0x08 12 1 4 Command Reset Global Minimum Maximum and Mean values The gl...

Page 31: ...e 1 are also valid but Data bytes are not used Reply Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x1F Channel Scaling MSB Scaling Scaling Scaling LSB DLC 0x06 Channel is the channel number that is requested and must be one of the following values 0x00 channel 1 0x01 channel 2 Scaling unsigned int 4 bytes representing the scaling 12 1 7 Command Set CAN timeout This setting only ap...

Page 32: ...tion from the sensor especially when sending multiple packages such as the FFT requests NB Using a large WAIT value will effectively halt the sensor from doing other work while it is transmitting The lowest possible value should be used 12 1 10 Command Get wait period between CAN messages Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0xE5 DLC 0x01 values above 1 are also valid but ...

Page 33: ...alues sent will be ignored If the data rate is set to a high value data might not be ready to send Please see 9 1 3 13 1 1 Command Set Periodic Messages Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x52 MsgNbr State Cmd SubCmd TimeMSB TimeLSB DLC 0x07 values above 0x07 are also valid but Data bytes are not used MsgNbr Message number currently 1 4 State 0x01 for ON 0x00 for OFF Cmd...

Page 34: ...f messages is capped at 2400 messages per second whereas the actual sample rate of the ADC is 4800 messages per second This is to prevent CAN bus overload Note Command 0x10 0x20 0x30 available from firmware version 0x00000118 13 2 J1939 type CAN Messages only for 2 active channels In this mode each channel will have its own ID Channel 1 will always be the same as the CAN Standard ID as set in 7 1 ...

Page 35: ... rate of SNR measurements required and on the data rate If the data rate i e is set to 300 Hz and the number of SNR measurements is set to 300 then the SNR will be outputted every second The peak minimum and maximum values of those 300 samples are used to calculated the SNR To turn off the SNR calculations send 0 as the number of samples 14 1 1 Command Set SNR sample numbers Command Sub Command Da...

Page 36: ...value of 0 0f and high value of 500 0f A float with a value of 0 0f will be all zeroes data bytes 2 5 Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 0x20 0x00 channel 1 0x00 0x00 0x00 0x00 0x00 low 0x80 DLC 0x08 Now we need to set the high value A float of 5000 0f will in bytes be 0x45 0x9c 0x40 0x00 Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 0x20 0x00 channel 1 0x45 0x9C 0x4...

Page 37: ... will have no effect until the calibration data is saved and the sensor restarted See command 17 1 1 16 1 1 Command Set Default Calibration Constants Issue the following command to set the default calibration constants Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x22 0xFF DLC 0x02 values above 2 are also valid but Data bytes are not used 17 Save Current Calibration Constants Afte...

Page 38: ...5 0xEF INFOTYPE DLC 0x02 values above 2 are also valid but Data bytes are not used INFOTYPE 0x01 to 0x03 reserved 0x04 Firmware Number is the version of the software in the sensor 0x05 reserved 0x06 Sensor Type a number specifying the type of sensor 0x14 Serial number same as is laser engraved on the sensor 0x30 Internal Temperature starting from firmware version 2 65 After this command has been r...

Page 39: ...d more than 10 000 times within the sensor s lifetime Issue the following command to save the current parameters Command Sub Command Data 0 Data 1 Data 2 Data 3 Data 4 Data 5 0x50 0xFF DLC 0x02 values above 2 are also valid but Data bytes are not used 20 Reset to Factory Settings This will reset the sensor to its factory settings The calibrations values will not be affected The settings are automa...

Page 40: ...ling to 10000 for channel 2 Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 0x1E 0x01 channel 2 0x00 0x00 0x27 0x10 DLC 0x06 Setup ADC Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 0x40 0x03 both channels 0x00 bipolar 0x80 gain of 128 0x00 0x1E 0x01 chop enabled 0x01 buffer enabled DLC 0x08 Setup periodic messages to follow ADCs and output a signed integer Byte 0 Byte 1 Byte 2 By...

Page 41: ... continuously made available when new functionality is added or improvements are made Please visit www lilliesystems com to check for updates and the latest version of this manual Should you be interested in updating the firmware using your own CAN device please contact us for a description of the protocol and NDA which must be signed prior to receiving the protocol ...

Page 42: ... range 0x0018 Error Set Std ID out of range 0x0019 Error Set IncomingFilterID1_2ID out of range 0x001A Error Set IncomingFilterID3_4ID out of range 0x001C Error Get Incoming Filter ID out of range 0x001D Error Get Sensor Information Sub Command out of range 0x0022 Error Enter Bootloader Data Not Valid 0x0023 Error Set Output On Off Data out of range 0x0024 Error Command Not Valid 0x0025 Error Set ...

Page 43: ...A2C SG2 M12 WWW LILLIESYSTEMS COM 43 of 44 ...

Page 44: ...pplications using Lillie System components To minimize the risks associated with Buyers products and applications Buyers should provide adequate design and operating safeguards Buyer acknowledges and agrees that it is solely responsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of Lillie Systems components in its applications notwi...

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