The Squarell Devices have two red LED patterns.

1. In case of a fixed red LED:

• This indicates that the Squarell device can not start because there is a CANbus connection problem. Please check the device CANbus cables, otherwise go to the Connection problems to solve the problem.
• The device has a corrupt configuration, please reload the DCF into the device using the latest iConfigure software.

 2. In case of a blinking red LED once every seccond:

The device has an error (in Booter mode): in that case the firmware can be corrupt. To solve the problem, performe a firmware upload using iUpdate tool. Please consult our support desk for further analysis.  

 

 

If you are digging into CANbus you will find a lot of protocols and technology features.

we like to give you a little guide in this CANbus world and give some comments on the main aspects

CANopen or Device NET:
These are protocols for CANbus.
• CANopen is used in machinery
• DeviceNET is used in harsh environment equipment
• J1939 is used for automotive environments

CANopen and DeviceNet are not used as a standard in the automotive world, so if you find equipment based on CANopen like interfaces, data loggers, sensor devices or anything else, it is not compatible with the FMS CANbus / J1939 protocol. To make proper use of such devices, J1939 support must be provided by the supplier.

11 and 29 bits
FMS CANbus / J1939 protocol is a 29 bits protocol.
CANopen and DeviceNet are 11 bits protocols

The 11/29 bits relate to the identification techniques of messages. A 11 bits protocol uses 11 bits to specify a message (2047 message ID’s) a 29 bits protocol has a wider range of dressing (65536 message ID’s). Over a CANbus 11 and 29 bits can be send without interfering each other. Squarell CANbus products support 11 and 29 bits messages.

You do not have to care about 11 or 29 bits. Make sure you read our J1939 documentation to know about the FMS CANbus / J1939 protocol.

It is also referred as CAN V2.0A = 11 bits, CAN V2.0B = 29 bits

CAN controller chips
Electronic CAN chip components can freely be obtained on the electronics market. You might think that it is easy to have CANbus when you have that chip. We see a lot of CAN enabled devices with a CAN chip, but when you ask what is used, the answer is that it will be programmed in the future.

We like to give you some info about this.
To buy a CAN Chip is easy, also electrical engineers can integrate it on the circuit boards without a problem. But then the hard part starts. The CAN chip gives electrical signals to the CANbus, but not a specific protocol. This protocol like J1939 must be programmed in the Chip. So to make the Chip work on the FMS CANbus a protocol software for that chip must be written and make that work in the total design. This is a very tedious job, and as CANbus is a very stable networking method, the protocol software makes the difference if your application works stable and flawless.

That’s why the integration of CANbus in systems is a intensive and expensive operation. We have identified that problem and provide easy solutions to make integration a simple and efficient process. An example is the 6602-21 iCommunicate.

 

Squarell CANdiode devices are also a FMS interface. The CANDiode is build in with the diode technology. It is not able to send any messages to the vehicle CANbus, even not an acknowledgment. It could just listen to the CAN communication between the 2 or more CAN devices.

In a FMS Interface CANbus:

1. There is mostly no CANbus device connected to the FMS interface. This will give an CANbus acknowledgment problem. If the FMS interface will not receive any acknowledge to the messages, it will think that there is no CANbus device connected and it will go to bus off mode. In that case there will be no communication so CANDiode can not send any CANbus data out.

2. On Direct CANbus there is more vehicle data available then on the FMS interface CANbus. This means more data, better vehicle performace and vehicle analyses.

 

• Please restart your PC.

• Please restart the Squarell Device which you are using to connect to the CAN Network.

• Check the power of the device set at least 10 volt - 1 ampere power supply.

• If you added a RS232 port AFTER the start up of iConfigure. Please restart iConfigure.

• If you use a RS232 cable be sure it is pin to pin without any crossed-lines.

• If you use USB to RS232 cable besure it has the possibility to use the handshake lines.

• If you use USB to RS232 cable: be sure you have the right drivers for your PC (never trust the included drivers in Windows, but use the latest drivers which came with your USB-RS232 interface). 

• Select the COM port which is connected to the currect Squarell Device.

• Sometimes the RS232 cable connector to the Squarell device is not tightly attached.

• Maybe your COMport is blocked by f.e a Hyperterminals session or ActiveSync (PDA synchronisation). Stop the applications which are blocking your RS232 port.

• Check if you use at the end of the CAN lines terminators. If not please connect at the end of the CAN lines terminators (part number 6698-00 or use CANbus Cables with termination part number 6692-U1).

• If your device has 2 CANbus ports (e.g Datalogger, iCommunicate, iCommdiode, CAN to CAN, CANdiode, J1708 Diode or K-line Diode) and one of the sides is not connected, check the DCF to see that the CANbus port settings are set properly. Please consult to our support desk to have the proper setting.

• If the problem still exist please take contact with the Squarell Helpdesk.

 

• Please restart iConfigure.

• Check the RS232 port settings in iConfigure, select CANnetwork-interface settings - RS232, select the proper COM port and the RS232 baudrate 115.200.

• Check the device addresses in your network, choose form iConfigure CANnetwork - set device addresses. The target device should have a device address similar to the device address in the DCF- class 001.

• If the problems still exist please check your connections. Otherwise go to the Connection problems.

 

 

• The “CANbus Ports” of a Squarell device are able to send/receive CAN data according to Multi- master systems. This means that there must be a CAN Device (one or more CANbus devices) available so that Squarell device can communicate.

• The “CANbus 2 Listen only Port” of a Squarell device is only able to receive CAN data according to Multi-master systems. This means that there must be CAN devices in communication with each other so that a Squarell device can listen and capture the CAN data on the “CANbus 2 Lisen only” Port. On this port it is not possible to transmit any data.  

It is very hard to tell if a truck has a FMS interface. In some cases it is registered in the configuration databases of the truck manufacturer that it was ordered with a FMS interface. If a FMS interface is retrofitted (at the dealer) the information will be not easy to recover. Retrofit changes are usually not updated in the factory systems. Dealers can only remember the fitting of the FMS interface based on workshop invoices. And if a truck is serviced at multiple locations, it becomes problematic.

So what should you ask your dealer?

Never ask your dealer: does my truck have CANbus. All trucks have CANbus, so they will say yes. But it does not mean that the FMS interface is inside.
Always ask your dealer: Does my truck have an activated FMS interface? Where is the connector? Did you test this FMS CANbus connection?  

The fuel consumption in a modern truck is calculated by the engine management computer. With sensor data like RPM, the mgr/stroke, temperature etc an estimate is calculated. In general the deviation between tanked liters and CANbus fuel consumption is between -3%..+3% .

Causes are:
• Tanked liters are never accurate as a full fill up can be -/+15 liters accurate
• The tanked liters are volume based, 10 degrees increase in diesel temperature = 1% in volume
• The engine mgt calculates in mgr/stroke and estimates the fuel consumption in liters
• The diesel fuel density can vary between 835 - 845 gr / liter
• Fuel usage in low-RPM ranges are less accurate then fuel usage at normal operation RPM ranges

Occasionally:
• Sometimes the internal parameters of the engine mgt calculations are incorrect, resulting in in-accuracy
• Engines with +6 years runing life have wear factors, not taken in consideration in the fuel calculations  

The CANdiode "CANbus 2 Listen only Port" on the Squarell devices is a protected port which only can read CANbus data from a CANbus system.

The design protects the CANbus against interference through the following functions:

• Optical isolation between CANdiode "CANbus 2 Listen only port" and device
• Power management designed to safeguard no interference on the CANdiode "CANbus 2 Listen only port"
• Software functions are disabled to write to a CANdiode "CANbus 2 Listen only port"
• Application settings prevent sending to a CANdiode "CANbus 2 Listen only port"
• CANdiode "CANbus 2 Listen only port" are equipped with a 5 pole connector. This prevents a wrong installation.

With more than 20.000 CANdiode implementations sold, no problems with the CANdiode "CANbus 2 Listen only port" technology are reported.

 

The Squarell GPS to CAN devices are capable of a send rate of 4 positions per second. The factory setting is 4 positions per second. When the GPS message is send over the CANbus the transmission interval can be selected. A corresponding CANbus send rate of 250 ms is recommended.  

Hardware Connection:

• Connect a Squarell Device with a RS232 Port (possible Devices 6632-21, 6602-21, 6603-21) to the PC with the RS232 cable (6691-32). If you do not have a RS232 port, please use a USB to RS232 interface (6691-16).
• Power the CAN to RS232 device via a 6692-U1 cable
• Connect the Squarell device using a 6697-XX cable to change the setting.
• Connect at the end of the CANbus line also the terminator. 

Using iService program:

• Start iService program.

• Select the used Com port, baudrate and CANbus speed, and click on OK. Usually in J1939 the baudrate is 250 kbaud.

• When iService connects to the CANbus, it checks what Squarell devices are connected on the CANbus. In this case in the above picture there is more than one Squarell device in the same CANbus, so you will see a list of connected devices, please select the right device. If you have problems with connecting to the CANbus please check your connections? Otherwise go to the Connection problems.

• Then the device settings will be shown in the iService window.

• To change the node address please click on "Default Device address"

• In the appeared window you will be able to give a new node ID of the availabe CANbus's.

  Some Squarell devices have more than one CANbus. In these devices, it is possible to change the node address separately for each CANbus.  
  

Using iConfigure program:

This feature is available since the iConfigure version: 09 Nov 2007.

• Start iConfigure program.

• Go to Menu "CAN Network" and select the "Interface settings".

• Set the proper Com port, baudrate and CANbus speed in the "Interface settings" and click on OK. Usually in J1939 the baudrate is 250 kbaud.

• Go to Menu "CAN Network" and select the "Set device address".

• When iConfigure connects to the CANbus, it looks what Squarell devices are connected on the CANbus. In this case in the above picture there is more than one Squarell device in the same CANbus, so you will see a list of the connected devices, please select the right device. If you have problems with connecting to the CANbus please check your connections? Otherwise go to the Connection problems.

• Select the Squarell device that you want to change the node ID and click on "Set address".

• In the appeared window you will be able to give a new node ID of the available CANbus's.

  Some Squarell Devices have more then one CANbus. In these devices, it is possible to change the node address separately for each CANbus.

 

• Open iConfigure,

• Go to Menu “CAN Network” and select the “Set device CANbus Speed”.
• When iConfigure connects to the CANbus, it checks what Squarell devices are connected on the CANbus. In this case in the above picture there is more than one Squarell device in the same CANbus, so you will see a list of the connected devices, please select the right device. If you have problems with connecting to the CANbus please check your connections? Otherwise go to the Connection problems.
• Select the Squarell device that you want to change the CANbus speed of and click on “Set Speed”.
• In the appeared window you will be able to select the CANbus speed of the availabe CANbus. Some Squarell devices have more then one CANbus. In these devices, it is possible to to select the CANbus speed separately for each CANbus.

 

Hardware Connection:
• Connect a Squarell device with a RS232 Port (possible Devices 6632-21, 6602-21, 6603-21) to the PC with the RS232 cable (6691-32). If you do not have a RS232 port, please use a USB to RS232 interface (6691-16).
• Power the CAN to RS232 device via a 6692-U1 cable
• Connect the Squarell device using a 6697-XX cable to change the device configuration.
• Connect at the end of the CANbus line also the terminator.

Configuring a Squarell Device:
It is very important to use the latest version of iConfigure program. Please download the latest version of iConfigure. Please remove the old version and install the latest version.
• Start iConfigure program.
• Go to Menu “CAN Network” and select the “Interface settings”. Set the proper Com port, baudrate and CANbus speed in the “Interface settings” and click on OK. Usually in J1939 the CANbus baudrate is 250 kbaud.
• Click on the pictogram “Open” on go to Menu and Select “Open Device Configuration (DCF)”.

  or 

• Go to the root of the Device Configration File (DCF) and click on Open
• The Device Configuration File will be loaded. The DCF is ready to be loaded to the Squarell Device.
• Go to Menu File and select “Write DCF to Device”.
• iConfigure connects to the CANbus to write the DCF to the Device.



• If you have problems with connecting to the CANbus please check your connections. Otherwise go to the Connection problems.  

The iLogCAN is configured via the PC software program iConfigure. A license of this program is required. One license of iConfigure is needed to iConfigure any kind of Squarell product.  

The Tacho to CAN and Tacho to CANdiode are devices with a powerlead coming for the special tacho cable. No power is taken from the usual CANbus connector side.

To connect power, the red (or brown) wire is 10-60 volt and the black one is ground.

As soon as the Tacho to CAN powers on the led will be red and change to green. Green indicates that the device is working and sees a CANbus system on it’s port. If the led is red, be sure to put ignition on so the CANbus network is activated (A CANbus network must consist of a minimum of 2 active devices)

The tachograph wire has besides the power wires also a grey wire and an opto sensor. This opto sensor connects to the screw on connector on backside of the 1318 compatible tachographs. Be sure that you pinch the plastic disk out of the tachograph to make the red blinking LED visible. The optical signal contains most of the data for tacho performance and workingstates.

A grey wire is for optional pulse signals. This must be connected to the PWM or 4 pulse/meter signal at the back of the tachograph.

The activation of the inputs depends on the configuration of the Tacho to CAN. This is set in the DCF in class 118.


 

To enter the license key in Windows Vista, the user needs to run iConfigure with full administrator permissions. These are the steps required to obtain these permissions:

• Start Windows Explorer.
• Navigate to the location where iConfigure is installed. For a standard installation, this location is
C:/Program Files/iConfigure
• Right-click the iConfig.exe icon, a context menu will pop up.
• From the context menu, choose Run as Administrator. iConfigure will start with full administrator
permissions.
• Proceed with the steps required to enter the license key.  

• Please connect your devices as above in the picture,
• Start the PC program iConfigure by clicking on the desktop icon or via the Start menu of Windows.
• Select “CANbus Monitoring” from the menu Monitor.
• Set the serial port and serial port speed. Set the Canbus speed only if you are really sure that you are using a different Canbus speed rather than 250Kb.
• Then click on the button “Connect to CAN network”
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections. Otherwise go to the Connection problems.
• Then click on the play button to play the simulation file.
• Select now the Truck Data Play file (extension = .txt).
• Click on OK button when the CANbus Monitor is ready with buffering all the CAN messages in the Play file. The system will replay the file to the CANbus.  

• Please connect your devices as above in the picture.
• Start the PC program iConfigure by clicking on the destop icon or via the Start menu of Windows.
• Select “CANbus Monitoring” from the menu Monitor.
• Set the serial port and serial port speed. Set the CANbus speed only if you are really sure that you are using a diffrent CANbus speed rather than 250Kb.
• Then click on the button “Connect to CAN network”.
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections. Otherwise go to the Connection problems.
• Then click on the play button to play the simulation file.
• Select now the Truck Data Play file (extension = .txt).
• Click on OK button when the Canbus Monitor is ready with buffering all the CAN messages in the Play file. The system will replay the file to the CANbus.  

• Please connect your devices as above in the picture.
• Start the PC program iConfigure by clicking on the desktop icon or via the Start menu of Windows.
• Select “J1708 Monitoring” from the menu Monitor.
• Select the proper serial port. Set the Serial Port speed only if you are really sure that you are using a different CANbus speed rather than 9600 baudrate.
• Then click on the button “Connect to J1708 network”.
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections? Otherwise go to the Connection problems.
• Then click on the play button to play the simulation file.
• Select now the Truck Data Play file (extension = .txt).
• Click on OK button when the Canbus Monitor is ready with buffering all the CAN messages in the Play file. The system will replay the file to the CANbus.  

 

 

• Please connect your devices as above in the picture.
• Start the PC program iConfigure by clicking on the desktop icon or via the Start menu of Windows.
• Select “CANbus Monitoring” from the menu Monitor.
• Set the serial port and serial port speed. Set the CANbus speed only if you are really sure that you are using a diffrent CANbus speed rather than 250Kb.
• Then click on the button “Connect to CAN network”
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections. Otherwise go to the Connection problems.
• When the CAN Monitor indicator changes to Connected there must be messages displayed on the CANbus Monitor. If you have problems with receiving CAN Messages please check your connections or CANbus Speed. Otherwise go to the Connection problems.

 

If you want to reccord the CANbus messages Please follow the next steps: 

• Then click on the Record button to give the file name and the path where to save the data.
(The extension of the recorded scan file will be *.txt file.)
• When you click on save button, the Canbus Monitor will start saving all CAN messages streaming on the CANline. There is also a counter which indicates how many messages are captured.

 

 

 
• Please connect your devices as above in the picture.
• Start the PC program iConfigure by clicking on the desktop icon or via the Start menu of Windows.
• Select “CANbus Monitoring” from the menu Monitor.
• Set the serial port and serial port speed. Set the CANbus speed only if you are really sure that you are using a diffrent CANbus speed rather than 250Kb.
• Then click on the button “Connect to CAN network”
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections. Otherwise go to the Connection problems.
• When the CAN Monitor indicator changes to Connected there must be messages displayed on the CANbus Monitor. If you have problems with receiving CAN Messages please check your connections or CANbus Speed. Otherwise go to the Connection problems.

 

If you want to reccord the CANbus messages Please follow the next steps: 

• Then click on the Record button to give the file name and the path where to save the data.
(The extension of the recorded scan file will be *.txt file.)
• When you click on save button, the Canbus Monitor will start saving all CAN messages streaming on the CANline. There is also a counter which indicates how many messages are captured.

 

• Please connect your devices as above in the picture.
• Start the PC program iConfigure by clicking on the desktop icon or via the Start menu of Windows.
• Select “J1708 Monitor” from the menu Monitor.
• Select the Serial port you are using. Set the Serial port speed to 115200kb
• Then click on the button “Connect to CAN network”.
• You will be connected to the CAN network if the CAN Monitor indicator changes to Connected. If you have problems with connecting to the CAN Network please check your connections. Otherwise go to the Connection problems.
• When you connect to J1708 bus the indicator will change to Connected and there must be messages displayed on the J1708 Monitor. If you have problems with receiving CAN Messages please check your connections or serial port settings? Otherwise go to the Connection problems.
• Then click on the Record button to give the file name and the path where to save the log File. (The extension of the recorded scan file will be *.txt file.)
• When you click on save button, the J1708 Monitor will start saving all J1587 and J1922 messages on the J1708. There is also a counter which indicates how many messages are captured.  

To upload a new firmware for the Squarel deviceTacho to CANdiode 6623-2x: download iUpdate tool

Installing the software
• Unpack the zip file.
• The zipfile contains the program iUpdate.exe and the BINFILES folder.

Hardware setup
• To upload the firmware please make sure that the Tacho to CANdiode is powered via the tachograph connector
• Make sure the COMport is COM 1 up to COM 4. If you have a high COM port number, please use Windows hardware setup to change the COM port to a COM1 to COM4.
• Create a program shortcut for the iUpdate.exe and the following text to the command line with parameters /Cx (x = COMport 1...4)  /R10

Upload process
• Start the program iUpdate.exe via the shortcut
• DO NOT INTERRUPT ANY STEPS AFTER THIS POINT!
• The connection to the device automaticly made and the uploading starts.
• The program will beep when the uploading is finished
(* Firmware = Booter / Application / Sleepmode booter / Sleepmode Application)  

To upload new firmware* for the Squarell devices, use iUpdate service tool.

 

Supported devices:

• All Squarell devices except Tacho to CANdiode. If you want to upgrade firmware for a Tacho to CANdiode 6623-xx please refer to the link FAQ Tacho to CANdiode.

Installing the software

• Download the iUpdate tool and unpack the zip file.
• The zip file contains the program iUpdate.exe and the BINFILES folder.
• In the BINFILES folder the firmware packs are stored.
• Install the iUpdate.exe file and the BINFILES folder in the same directory.

Hardware setup

• Use a 6632-21 or 6602-21 as uploader, connect via RS232 to the PC and power up via the CANbus port.
• Set the device address of the CANbus port of the uploader to 253.
• This device is now only to be used as an uploader setup.
• Make sure the COMport is COM 1 up to COM 4. If you have a high COMport number, please use Windows hardware setup to change the COMport to a COM1 ... COM4.
• Create a program shortcut for the iUpdate.exe with parameters  /Cx (x= COMport 1...4).
• Connect the device to be configured to the CANbus via a 6697-xx cable.

Upload process

• Start the program iUpdate.exe via the shortcut.
• DO NOT INTERRUPT ANY STEPS AFTER THIS POINT!
• The connection to the device is automatically made and the uploading starts.
• The program will beep when the uploading is finished.

 (* Firmware =  Booter / Application / Sleepmode)

 

The FMS CANbus standard is an agreement between the european commercial vehicle manufacturers to standardize vehicle information from the truck and bus.

The goal is to provide means to get vehicle information for transport companies and interested parties in a known and standardized way. The technology for this information is CANbus.

The FMS CANbus is now available on european truck brands like:
• DAF
• Mercedes Benz
• Scania
• Volvo
• MAN
• Iveco
• Renault

We have noticed that every truck brand with the FMS standard is not fully supporting the full set of information. We also see that truck manufacturers are providing other (extra) vehicle information over the CANbus.

The situation looks like this:

Requirements per brand
We have knowledge of the brands and models where FMS CANbus is available, and which functions can be used. Also parts information, connector types and availability information is.

To use FMS CANbus on your truck you’ll need a brand specific FMS interface. These FMS interfaces have different names in every brand. We have noticed that at this moment the service networks are not aware of the FMS standard, so if you ask them about FMS, they will not find it in their workshop systems or handbooks. For every brand the interface box has a specific name. Usually with help from the factory or importer/central distributor the right information can be obtained.

FMS standard deviations
FMS standard not fully supported:
• Trucks are not equipped with the right sensors. (Axle weight)
• Trucks need a new version of the internal CANBus systems
• Commercial interest to introduce FMS functions step by step

Providing other CANbus information:
• Some manufacturers provided CANbus functions before the FMS standardization, and based some solutions on it. We have to hope that this information will not be withdrawn.
• CANbus implementations in the vehicles already provide a lot of CANbus information.
• With just FMS standard some customer oriented features can’t be supported, like actual values. By providing more data, more customer focused solutions can be build
• In the vehicle information concept, body builder companies can use that CANbus to integrate better with the truck. Some brands already have such infrastructure in place.
• It depends on truck configuration is other messages are available. For example, PTO data can only
be available when PTO is mounted (only certain versions) same with ESP, Automatic gearshift and Cruise control signals.

Retrofitting
• Retrofit FMS interfaces is usually possible. But first fitted FMS interfaces are about 60% chapter then retrofit versions.


We help you out
Squarell helps customers to use FMS CANbus efficiently by supporting projects and counselling. You can contact us to help you with CANbus.  

Yes, the GPS to CAN devices are enabled for EGNOS and WAAS augmentation signals. The EGNOS and WAAS augmentation data is a correction signal send via the GPS sattelites. In this signal the actual correction codes are send for the satellites. This means that the position is more accurate and stabil.

EGNOS is the European correction signal.

WAAS is the American correction signal.  

Question:
When I want to test one of my:

• 6603-21 iCommDiode,
• 6623-2X Tacho to CANDiode
• 6626-21 CAN Diode
• 6628-31 J708 Diode
• 6630-31 K-Line Diode

devices, the listen only port does not receive any data.

Cause:
On CANbus at least two functioning devices must be present. When one of the devices sends a CANbus message, the other device will acknowledge this. Then there will be CANbus communication between these two CANbus devices.

If you connect a CANbus device with a Listen only port to one sending CANbus device then the data send by the other device will NOT be acknowledged. The sending device will retry several times and on a certain moment it will go to BUS OFF mode. It seems then that device is not working.

How to solve it:
Just connect an extra CANbus device to the CANbus, so that the messages are acknowledged. The listen only port will now relay the data which is available on the CANbus.

Other causes:
In the DCF the CANbus port settings are not correct. Check the class040 CANbus ports and check if the listen only port is set to J1939 or Layer2 (depending on the purpose of the device).

 

Squarell has knowledge of all FMS implementations from truck manufacturers. We have seen many deviations from FMS standard and also found some versions with incorrect data and behaviour.

All this knowhow is implemented in the Squarell CANdiode device and options. This way the Squarell products will compensate the shortcomings of current FMS interfaces and extend the data to a full set for advanced Fleet Management. The result is trouble free and easy usage of FMS CANbus data, and predicatable behaviour. 

The strain gauge has been in use for many years and is the fundamental sensing element for many types of sensors, including pressure sensors, load cells, torque sensors, position sensors, etc.

The majority of strain gauges are foil types, available in a wide choice of shapes and sizes to suit a variety of applications. They consist of a pattern of resistive foil which is mounted on a backing material. They operate on the principle that as the foil is subjected to stress, the resistance of the foil changes in a defined way.













The strain gauge is connected into a Wheatstone Bridge circuit with a combination of four active gauges (full bridge), two gauges (half bridge), or, less commonly, a single gauge (quarter bridge). In the half and quarter circuits, the bridge is completed with precision resistors.










The complete Wheatstone Bridge is excited with a stabilised DC supply and with additional conditioning electronics, can be zeroed at the null point of measurement. As stress is applied to the bonded strain gauge, a resistive change takes place and unbalances the Wheatstone Bridge.

This results in a signal output, related to the stress value. As the signal value is small, (typically a few millivolts) the signal conditioning electronics provides amplification to increase the signal level to 5 to 10 volts, a suitable level for application to external data collection systems such as recorders or PC Data Acquistion and Analysis Systems.






Some of the many Gauge Patterns available

Most manufacturers of strain gauges offer extensive ranges of differing patterns to suit a wide variety of applications in research and industrial projects. They also supply all the necessary accessories including preparation materials, bonding adhesives, connections tags, cable, etc. The bonding of strain gauges is a skill and training courses are offered by some suppliers. There are also companies which offer bonding and calibration services, either as an in-house or on-site service.

More about the Strain Gauge.
If a strip of conductive metal is stretched, it will become skinnier and longer, both changes resulting in an increase of electrical resistance end-to-end. Conversely, if a strip of conductive metal is placed under compressive force (without buckling), it will broaden and shorten. If these stresses are kept within the elastic limit of the metal strip (so that the strip does not permanently deform), the strip can be used as a measuring element for physical force, the amount of applied force inferred from measuring its resistance.

Such a device is called a strain gauge. Strain gauges are frequently used in mechanical engineering research and development to measure the stresses generated by machinery. Aircraft component testing is one area of application, tiny strain-gauge strips glued to structural members, linkages, and any other critical component of an airframe to measure stress. Most strain gauges are smaller than a postage stamp, and they look something like this:















A strain gauge’s conductors are very thin: if made of round wire, about 1/1000 inch in diameter. Alternatively, strain gauge conductors may be thin strips of metallic film deposited on a nonconducting substrate material called the carrier. The latter form of strain gauge is represented in the previous illustration. The name “bonded gauge” is given to strain gauges that are glued to a larger structure under stress (called the test specimen) The task of bonding strain gauges to test specimens may appear to be very simple, but it is not. “Gauging” is a craft in its own right, absolutely essential for obtaining accurate, stable strain measurements. It is also possible to use an unmounted gauge wire stretched between two mechanical points to measure tension, but this technique has its limitations.

Typical strain gauge resistances range from 30 Ohms to 3 kOhms (unstressed). This resistance may change only a fraction of a percent for the full force range of the gauge, given the limitations imposed by the elastic limits of the gauge material and of the test specimen. Forces great enough to induce greater resistance changes would permanently deform the test specimen and/or the gauge conductors themselves, thus ruining the gauge as a measurement device. Thus, in order to use the train gauge as a practical instrument, we must measure extremely small changes in resistance with high accuracy.

Such demanding precision calls for a bridge measurement circuit. Unlike the Wheatstone bridge shown in the last chapter using a null-balance detector and a human operator to maintain a state of balance, a strain gauge bridge circuit indicates measured strain by the degree of imbalance, and uses a precision voltmeter in the center of the bridge to provide an accurate measurement of that imbalance:















Typically, the rheostat arm of the bridge (R2 in the diagram) is set at a value equal to the strain gauge resistance with no force applied. The two ratio arms of the bridge (R1 and R3) are set equal to each other. Thus, with no force applied to the strain gauge, the bridge will be symmetrically balanced and the voltmeter will indicate zero volts, representing zero force on the strain gauge. As the strain gauge is either compressed or tensed, its resistance will decrease or increase, respectively, thus unbalancing the bridge and producing an indication at the voltmeter. This arrangement, with a single element of the bridge changing resistance in response to the measured variable (mechanical force), is known as a quarter-bridge circuit.

As the distance between the strain gauge and the three other resistances in the bridge circuit may be substantial, wire resistance has a significant impact on the operation of the circuit. To illustrate the effects of wire resistance, I’ll show the same schematic diagram, but add two resistor symbols in series with the strain gauge to represent the wires:















The strain gauge’s resistance (Rgauge) is not the only resistance being measured: the wire resistances Rwire1 and Rwire2, being in series with Rgauge, also contribute to the resistance of the lower half of the rheostat arm of the bridge, and consequently contribute to the voltmeter’s indication. This, of course, will be falsely interpreted by the meter as physical strain on the gauge.

While this effect cannot be completely eliminated in this configuration, it can be minimized with the addition of a third wire, connecting the right side of the voltmeter directly to the upper wire of the strain gauge:















Because the third wire carries practically no current (due to the voltmeter’s extremely high internal resistance), its resistance will not drop any substantial amount of voltage. Notice how the resistance of the top wire (Rwire1) has been “bypassed” now that the voltmeter connects directly to the top terminal of the strain gauge, leaving only the lower wire’s resistance (Rwire2) to contribute any stray resistance in series with the gauge. Not a perfect solution, of course, but twice as good as the last circuit!

There is a way, however, to reduce wire resistance error far beyond the method just described, and also help mitigate another kind of measurement error due to temperature. An unfortunate characteristic of strain gauges is that of resistance change with changes in temperature. This is a property common to all conductors, some more than others. Thus, our quarter-bridge circuit as shown (either with two or with three wires connecting the gauge to the bridge) works as a thermometer just as well as it does a strain indicator. If all we want to do is measure strain, this is not good. We can transcend this problem, however, by using a “dummy” strain gauge in place of R2, so that both elements of the rheostat arm will change resistance in the same proportion when temperature changes, thus canceling the effects of temperature change:















Resistors R1 and R3 are of equal resistance value, and the strain gauges are identical to one another. With no applied force, the bridge should be in a perfectly balanced condition and the voltmeter should register 0 volts. Both gauges are bonded to the same test specimen, but only one is placed in a position and orientation so as to be exposed to physical strain (the active gauge). The other gauge is isolated from all mechanical stress, and acts merely as a temperature compensation device (the “dummy” gauge). If the temperature changes, both gauge resistances will change by the same percentage, and the bridge’s state of balance will remain unaffected. Only a differential resistance (difference of resistance between the two strain gauges) produced by physical force on the test specimen can alter the balance of the bridge.

Wire resistance doesn’t impact the accuracy of the circuit as much as before, because the wires connecting both strain gauges to the bridge are approximately equal length. Therefore, the upper and lower sections of the bridge’s rheostat arm contain approximately the same amount of stray resistance, and their effects tend to cancel:















Even though there are now two strain gauges in the bridge circuit, only one is responsive to mechanical strain, and thus we would still refer to this arrangement as a quarter-bridge. However, if we were to take the upper strain gauge and position it so that it is exposed to the opposite force as the lower gauge (i.e. when the upper gauge is compressed, the lower gauge will be stretched, and visa-versa), we will have both gauges responding to strain, and the bridge will be more responsive to applied force. This utilization is known as a half-bridge. Since both strain gauges will either increase or decrease resistance by the same proportion in response to changes in temperature, the effects of temperature change remain canceled and the circuit will suffer minimal temperature-induced measurement error:















An example of how a pair of strain gauges may be bonded to a test specimen so as to yield this effect is illustrated here:








With no force applied to the test specimen, both strain gauges have equal resistance and the bridge circuit is balanced. However, when a downward force is applied to the free end of the specimen, it will bend downward, stretching gauge #1 and compressing gauge #2 at the same time:















In applications where such complementary pairs of strain gauges can be bonded to the test specimen, it may be advantageous to make all four elements of the bridge “active” for even greater sensitivity. This is called a full-bridge circuit:















Both half-bridge and full-bridge configurations grant greater sensitivity over the quarter-bridge circuit, but often it is not possible to bond complementary pairs of strain gauges to the test specimen. Thus, the quarter-bridge circuit is frequently used in strain measurement systems.

When possible, the full-bridge configuration is the best to use. This is true not only because it is more sensitive than the others, but because it is linear while the others are not. Quarter-bridge and half-bridge circuits provide an output (imbalance) signal that is only approximately proportional to applied strain gauge force. Linearity, or proportionality, of these bridge circuits is best whenthe amount of resistance change due to applied force is very small compared to the nominal resistance of the gauge(s). With a full-bridge, however, the output voltage is directly proportional to applied force, with no approximation (provided that the change in resistance caused by the applied force is equal for all four strain gauges!).

Unlike the Wheatstone and Kelvin bridges, which provide measurement at a condition of perfect balance and therefore function irrespective of source voltage, the amount of source (or “excitation”) voltage matters in an unbalanced bridge like this. Therefore, strain gauge bridges are rated in millivolts of imbalance produced per volt of excitation, per unit measure of force. A typical example for a strain gauge of the type used for measuring force in industrial environments is 15 mV/V at 1000 pounds. That is, at exactly 1000 pounds applied force (either compressive or tensile), the bridge will be unbalanced by 15 millivolts for every volt of excitation voltage. Again, such a figure is precise if the bridge circuit is full-active (four active strain gauges, one in each arm of the bridge), but only approximate for half-bridge and quarter -bridge arrangements.

Strain gauges may be purchased as complete units, with both strain gauge elements and bridge resistors in one housing, sealed and encapsulated for protection from the elements, and equipped with mechanical fastening points for attachment to a machine or structure. Such a package is typically called a load cell.  

Terminators are resistors which must be fitted at the physical longest CANbus connection (the longest trunks). In well designed CANbus networks 2 terminators must be present. The terminators are necessary to avoid signal reflections and thus disturbances to the electrical signal and assure the right DC levels on the CANbus.

If CANbus systems are not terminated correctly disturbances can occur giving unpredictable results in operational environments. Eg. when a non terminated network works on your desk, it does not mean it will do so in operation.

According to the standard ISO 11898 the CANbus must be terminated

40% of all CANbus problems reported are due to incorrect cabling and wrong termination. When a CANbus system has incorrect termination, CANbus malfunction can occur without any reason, even if the system has worked for a long time.  

The Squarell GPS device 6619-21 and 6620-21 are Dead Reckoning GPS devices. Dead Reckoning is a technology to calculate the GPS position when the satellite signal is not present or to weak. The position calculation is based on a gyroscope and speed signal. That way a good fix is possible in urban canyons, tunnels, parking garages and forest areas. The picture below shows benefits of the Dead Reckoning GPS system.


 

In 1999, the truck manufacturers Scania introduced a FMS interface on their models as an accessory. This FMS interface was the first step in opening up motor management data from heavy vehicles. 2 years later on the Transport logistics fair in Munich, the European truck brands agreed on supporting such a concept to open up vehicle data for the transport companies.

The truck brands Scania, Volvo, MAN, Mercedes Benz, DAF, Iveco and Renault favored this idea and some months later the first FMS implementations were released in their new truck models.

Nowadays FMS CANbus is available in the truck world, but still a few can benefit from it.

The possibilities of FMS standard.
The following data can be retrieved from the FMS CANbus
• Actual vehicle speed
• Total distance of the truck during life
• Actual fuel consumption
• Total fuel consumption during truck life
• Tachograph speed
• Tachograph driver knobs status
• Tachograph warnings of exceeding drive time deregulations
• Tachograph overreving and direction indicator
• Vehicle Identification (VIN number)
• Brake Switch
• Cruise Control status
• Clutch switch
• PTO on/off
• Throttle position
• Axle weight and position
• Total running hours
• Next regular maintenance
• Engine temperature

The detailed specification can be retrieved from www.fms-standard.com

Current status (2006-2007)
At this moment only the latest models on the market support the main FMS signals. FMS CANbus implementations of the truck makes are using the spec as a part of their brand specific CANbus interface. In several truck models there is more CANbus data available. It also depends on truck configuration and model year. Many dealers have problems in switching on FMS for their customers. It is also not clear if a truck is equipped with an FMS interface.

The first changes in FMS standard is announced: The Digital tachograph data will be exported. Support is planned in 2008-2009.  

J1939 is a CANbus protocol.

But what does this mean?

We will give you some practical information about the J1939 CANbus standard without all the technical details.

What is a protocol?

A protocol is the description how data is communicated over the CANbus. In the J1939 protocol it is agreed:

• The speed of the CANbus
• The messages and the separate data in the messages
• How to send and receive the data from the CANbus
• How the CANbus devices should behave when powered, transmission errors occur, etc.
• More technical aspects of communication which are usually hidden for the user.

What should I know about J1939?

If you use the Squarell products the technical details of CANbus are solved in the product. But to use the J1939 protocol it is required to know:

• What the message looks like
• What data is in the message

 

In the documentation of J1939 this is described in detail. It describes the messages as a PGN and the data items as a SPN.

(see http://www.sae.org and search for J1939-71 for the full description)

 

• The "CANbus port" of a Squarell device is able to send/receive CAN data according to Multi-master systems. This means that there must be a CAN Device (one or more CAN bus devices) available so that Squarell device can communicate.
• The "CANbus 2 Listen only port" of a Squarell device is only able to receive CAN data according to Multi-master systems. This means that there must be CAN Devices in communication with each other so that Squarell Device can listen and capture the data on the "CANbus 2 Listen only port". On this port it is not possible to transmit any data.     

 

1. Software installation
To install the iConfigure software on a Windows PC, perform the following steps:
I. Preparation: Administrator rights are required to install the iConfigure software.
II. Download the iConfigure program from http://www.squarell.com/Support/Downloads. The page contains all the files and documentation required to use the Squarell products.
III. Open the iConfigure setup file and use the installation wizard to complete the installation.

2. Requesting the activation the iConfigure software
Start the iConfigure software to activate the iConfigure license. On the first screen the License Request Code is displayed. Mail this code to sales@squarell.com. Include the company details, name and contact phone number.

Within 24 hours an activation code is send to the mail address. Even without the activation code the software is fully functional exept that no configurations can uploaded to the Squarell devices. Users are able to explore, develop and save the configurations on the PC.

3. Entering the activation code
When Squarell receives the request code an activation key is generated and send by e-mail.

To enter this activation key, make sure your are logged in with administrator rights, then open iConfigure. After entering the license key, press Submit

Before the license period ends iConfigure will notify how many days are left until the program expires. The license expiration date can also be found at the Help menu, option License.

 

This problem is caused by Windows.

When there is a COM3 on your computer this will be shown in the device manager and in software programs like iConfigure, COM3 will be given as "ok to use" by Windows.
But when there is no COM3 on your computer this will not be shown in the device manager. But a lot of times Windows will give COM3 as "ok to use" by Windows in software programs.
This situation causes that iConfigure will allways show COM3 as available at the Interface settings even if there is no COM3 on your computer.

So please check in the device manager of your computer which COM ports are available and which COM port you will use. Select this COM port in iConfigure at CAN Network-Interface settings.
 

 

The Squarell Devices can reads CANbus parameters from the vehicle CANbus. If some CANbus parameters (like Total Vehicle Distance, Total Fuel Used and Total Engine Hours) are not supported by the vehicle CANbus, Squarell Devices can still calculate this parameters using the other CANbus parameters.  In that case all calculated CANbus parameters will starting from 0 and counting up.

 

The Squarell devices are storing all the calculated parameters in the stored memory. This data is not lost when the power of the devices goes off.

 

When a Squarell device is connected to a vehicle CANbus, and some parameters are not supported by the vehicle CANbus it will detect that and start automaticaly with calculations. If you remove this Squarell device from the vehicle and install this device into an other vehicle without cleaning the device from the old data, the device will continue with counting up from the old values.

 

To prevent this incorrect data Squarell devices must be cleanded from the old data every time when it is connected to an other vehicle.

 

 

    

 

 

 

 

 

 

On certain (older) FMS CANbus vehicles the Squarell Telematics interface sends the total distance and total fuel starting with 0 and counting up.

Cause

The FMS CANbus of that specific truck is not sending the total values. Only in certain dashboard equipment the total values are calculated. The Squarell Telematics Device cannot get that data and calculates the total distance and total fuel from the other CANbus data. As the start values of the Telematics interface are 0, the values start with 0.

Solution
To set the starting values of the Squarell temelatics solution a message is implemented to set the total values. Please consult the protocol description of the Squarell Telematics interface for more details.