If the steps follow each other too quickly, stuttering may occur as soon as the syringe is pressed. This problem appears sometimes when the command Titrate(…;Fast) is used. For a slow titration (Titrate(…;Slow)) the step motor burette should function properly. If fast titration is required, try increase the waiting time between the steps (only possible in Author mode):

  1. Start the Coach activity ‘Acid-base titration with CMA burette’, or comparable.
  2. In the Program window, just below its title bar, drag the window edge down to open the procedure editor.
  3. Increase the value of the variable WaitingTime (for instance into 0.005).
  4. Drag the edge back to close the editor window and retry the activity.

During the ‘Titrate’ command the step motor is moving backward while the ‘BackMotor’ command moves the step motor forward. Exchange the wires connected to the outputs A1 and B1 of CoachLab II+.

This can be due to the motor itself or to the type of syringe. Check the following:

  • If the power adapter of your CoachLab II/II+ has a voltage switch, make sure it is set to 12 Volts
  • For an older type of titrator: the syringe deforms when it is pushed too hard into the titrator and clamps the piston. The syringe should be placed loosely inside the titrator.
  • For a newer type of titrator: use the supplied syringe as it has less friction.
  • Sometimes the spindle is fitted very tightly to the housing of the motor, as it causes extra friction during the motion. Try to create more space between the spindle and the housing (ca. 1-2 mm spacing) using an Allen key.

Coach 6

There are several reasons why these error messages appear. In any case, it means that the video can not be loaded in Coach. A few suggestions:

  • The required codec is missing on your computer. In this case, you can also not play the movie in a standard video player. Solution: install the required codec, e.g. through a codec pack such as the K-Lite Codec Pack.
  • A 64-bit codec pack is installed. Coach can not handle 64-bit packages. Solution: replace the codec by a 32-bit version.
  • DirectX or QuickTime is not up to date. Make sure you download and install DirectX (version 9c or higher) and QuickTime (version 7.2 or higher).
  • The QuickTime source filter is not installed. Coach needs this source filter to import movies. Normally it is installed together with Coach. Solution: Make sure the QTSourcePX32.dll file is located in the folder C:\ Program Files\CMA\Coach6\Common. If not, download it here and install it.
  • It is not possible (both inside and outside Coach) to view a QuickTime movie from a network location. Solution: move or copy the movie to a local folder on the computer.

This bug has been fixed in Coach 6.43a. Please update to the latest version of Coach.

If you do a new measurement in Coach 6, the previous result disappears. Although the old result is still visible in the diagram (greyed out), you can not read the graph any more. To ensure that you keep the old results, the column with that data needs to be copied. The option “Column copy” appears when you right click on a chart or table. In the submenu, you must specify which column should be copied. For time-based measurements, the time column does not need to be copied.

This problem occurs during the installation of the Coach 6 client (while unpacking ISScript11.msi). The error “1607: Can not install InstallShield Scripting Runtime.” appears and the installation aborts afterwards. N.B. This problem was seen on a Novell 6.5 SP5 network (ZENworks).

  • Information about possible causes and solutions can be found in this Microsoft support article.
  • Make sure that the account from which Coach was installed (or the group of which the account is a member) has the privilege “Impersonate a Client After Authentication”. Microsoft introduced this privilege in a Service Pack for safety reasons. If this privilege is missing from the policies, MSI installations abort even with administration rights. For additional information, see this Microsoft support article and this InstallShield article.
    Follow these steps to set the permissions:

    1. Log in to the client with administration rights.
    2. Go to the Start Menu, click Run and start “secpol.msc” (Local Security).
    3. In the left window go to Local Policies > User Rights Assignment.
    4. Search for “Impersonate a client after authentication” and double-click the item.
    5. The list should show your current account (most likely “Administrators”). If this is so, you can close the local security settings and proceed with the installation. Otherwise, click ‘Add User or Group’ and proceed with the next steps.
    6. Click on “Advanced” and click “Find” in the dialog “Users or Groups”.
    7. If you cannot find the account, you can always assign the right to “Everyone”.
    8. Close the Security Policy Editor and restart the installation of Coach 6 client.

    You can remove the privilege after the installation is complete. If the above solution does not work, download the following file and unzip it into a temporary folder. Right-click the extracted .msi file and choose Install. Start the client installation Coach 6 again.

This is a generic error message from the Windows installer. There can be many possible causes, usually pointing to a configuration error on the local computer. For more information, see the following Microsoft support article and external link. A web search for “error 1603 during installation” can provide additional information.

Coach 6 (starting from version 6.3) supports both 64-bits and 32-bits Windows platforms. Please update your Coach to the latest version.

Coach 7

Whenever new functionality is added to Coach, or when enough bugs are fixed, a new minor version of Coach will be released. You can expect two or three updates per year, one of which will be likely prior to the start of the academic year.

Coach 7 is now available for Chromebooks. The current version for Chromebooks supports Modeling and Data Video. Download the Coach 7 app from the play store. A BYOD license is required to activate the app.

Coach 7 works on computers with Windows 7 or newer, or OS X 10.11 El Capitan or newer. The Coach 7 app can be used on Chromebooks.

Coach 7 for Tablets

2017Android: most tablets with Android 5, 6 and 7, with a minimum of 1 GB memory and an ARM-processor. The performance of the app is strongly dependent on the hardware of the tablet. For ease of use we recommend a tablet of 9″ or larger.
iPad: all iPads with iOS 8 or higher are supported. This prevents Coach from running on the first generation iPad (2010) only. We recommend the use of an iPad with at least 1 GB of internal memory (all models since 2012). We do not recommend the use an iPad Mini due to the limited screen size.

In Coach 7 for tablet version 7.1 the layout screen is locked by default. To unlock it:
– Open an Activity/Result.
– Tap the Menu icon located at the right side of the Activity toolbar and select Display > Locked Layout.
Now you will be able to create new panes, to resize panes and to switch the content of the panes.

You can share/upload Coach Activities made in Coach on tablet.

Method 1: via Activity/Result list
Activities and Results created on tablet are stored in the User folder.
– Open the User folder: tap the Open icon and tap User.
– Long tap an Activity or Result name until menu with options Open, Share, Delete and Cancel appears.
– Select Share and select the way you want to share the file.

Method 2: via menu in an Activity/Result 

– Open an existing Activity/Result or create a new Activity/Result.
– Tap the Menu icon in the Activity toolbar and select File > Share.
– Select the way you want to share the file.

iOS: tap the attachment, a cma7 or cmr7 file, and select Copy to Coach 7.  Coach 7 App starts en opens the activity. The Activity will be saved in the Coach 7 User, in the folder called Inbox.
Android: tap the attachment, a cma7 or cmr7 file, Coach 7 App starts en opens the activity. You can also save the file into Device Storage > Download.

Yes you can; how to do it may differ for different cloud services.
iCloud: Tap a cma7 or cmr7 file, tap the Download button and select Copy to Coach 7.  Coach 7 App starts and opens the activity.
Dropbox: Tap a cma7 or cmr7 file, tap the Menu icon, select Export and Select Open In … then select Copy to Coach 7.  Coach 7 App starts and opens the activity.
GoogleDrive: Go to My Files or Google Drive, tap a cma7 or cmr7 file, Coach 7 App starts and opens the activity (notice that Coach 7 App has to be closed first otherwise you may get an error).


Yes you can download activities from websites and open them directly in Coach, for example activities offered on the CMA website (see Teaching Resources page).
iOS: tap the link to cma7 or cmr7 file, tap Open in “Coach 7”. Coach 7 App starts and opens the activity.
Android: tap the link to cma7 or cmr7 file, the activity will be copied into the Device Storage > Download folder. Go to My Files App and tap the downloaded activity, Coach 7 App starts and opens the activity.
You can also copy the file into Documents > Coach 7 then the file will be visible in the User folder of Coach 7 App.

Note: for some browsers it can happen that a Coach Activity is interpreted as txt file instead of cma7 or cmr7 file. This is not a problem as Coach 7 App can open such file with extension txt. Touch the downloaded txt file and select Open with Coach 7 or copy the file to the User folder of Coach 7. When the coach activity file with txt extension will be opened via Open icon in Coach App then it will modify its extension back to cma7 or cmr7.

To limit the size of  Coach 7 Apps the CMA Projects are not included in Coach anymore. These projects can be downloaded now via the Download button available in the Main Toolbar after opening Coach. After this button is pressed Coach makes contact with the CMA website and checks which language projects are available on the CMA website.
Tap the language to select the CMA projects to be downloaded and tap the Download icon.
Depending on your Internet connection downloading of files can take some time.


Coach 7 Apps have a multilingual user interface and offer many languages. To switch the language of the Coach user interface:
– Start Coach 7 App.
– Tap the Login icon and login as Student or Author user.
– Tap the Menu icon (located at the right site of the Main Toolbar) and select Options > Switch Language then select the desired language from the list.
– Stop Coach 7.
– Start Coach 7 again, the user interface will be displayed in the selected language.

Coach 7 – this App is meant for owners of a Coach 7 Tablet Site License. The App can be downloaded for free but to be able to use it you need a valid Tablet Site License code (not the desktop license code). Contact CMA or your local dealer to purchase the Coach 7 Tablet License for your school or institution. The latest version 7.1 of this App offers Data Video and Modeling features of Coach 7.
Coach 7 Modeler – this App can be purchased in App stores (price Euro 9.99) and offers Modeling features of Coach 7.
Coach 7 Modeler and Video – this App can be purchased in App stores (price Euro 12.99) and offers Data Video and Modeling features of Coach 7.


Coach 7 Activities and Results are exchangable between different platforms: Windows, OS X, iOS and Android. No matter what the mix of technology is in the classroom or the school is, all users share the same user experience.

Only modern CoachLab II+ models with a USB-port are supported. Older models with a serial port are not supported, not even with an adapter cable. CoachLab II+ models without a serial number, or with serial number SAG08XXXXX and SAG09XXXXX contain an internal serial to USB converter and require low-level drivers to work properly.

All CMA sensors that were supported in Coach 6, are also supported in Coach 7. Approximately 200 sensors and sensor calibrations are supported, including a selection of Vernier sensors.

The following CMA interfaces are supported:

  • On Windows: CLAB, €Lab, €Sense, €Motion, MoLab, CoachLab II+ and VinciLab.
  • On OS X: CLAB, €Lab, €Sense, CoachLab II+ and VinciLab.

The CoachLab II interface (before 2008, with a serial port) and other old CMA interfaces are no longer supported.

Yes, *.cma, *.cmr, *.cma7 and *.cmr7 files are interchangeable between all supported operating systems.

Yes, most activities from Coach 6 can be opened directly in Coach 7, but not the other way around. There are a few cases where conversion is not possible, e.g. when a text contains an image. In these cases, the activity will have to be manually modified.

Data video

Two important things play a role here: in a Data video measurement, every data point is linked to a specific pixel in a specific video frame and using the option Smooth replaces the original measurement data. These two facts conflict, because:

  • If the measurement would be interpolated and more data points would be generated, the 1-on-1 connection between a data point and a frame is lost
  • The X and Y values of the data points will change by the smoothing operation, which makes the connection to a specific pixel impossible

In short, it is not possible to use the Smooth option.

Note (09/10/2017): from Coach version 7.3 (september 2017) onwards it is possible to do Smoothing in video measurements due to a change in how data processing works.

Alternatively you can smooth your data by using a formula. Click with the right mouse button in the Data table and select Add a New Variable… > in Data Series > Formula. Fill in the formula “Spline(X;Y;-1)” and replace X and Y with the corresponding variable names from the video measurement (default: P1X and P1Y).

Coach 7 supports many common video formats and containers: mov, mp4, m4v, 3gp, 3g2, avi, wmv, asf, mpg, mpeg and m1v. In some cases videos cannot be imported, for example if they have been recorded with a smartphone. Please use a video conversion tool such as Any Video Converter to convert your video to a format suitable for Coach. You can find a short guide to perform the conversion here.

Note: During the installation of Any Video Converter it is possible that some (unwanted) toolbars or other programs are also installed. These installations are optional and can be prevented by selecting “Customize Install” during installation and deselecting these additional programs.

Any camera that records video at 15 frames per second (fps) or more should suffice. Almost all digital photo camera’s, video camera’s, (built-in) webcams, high-speed camera’s and most smartphones with video functionality will work. CMA specifically offers a webcam with tripod and built-in lighting for this purpose. The webcam records video at 30 frames per second and works without the installation of any drivers under Windows 7 or newer.

If this problem occurs in Coach 6, it may be the result of a 64-bit codec pack that was installed. Coach can only handle 32-bit codecs. Reinstall the codec pack, but choose a 32-bit compatible version.
If this problem occurs in Coach 7 (or if the above solution does not work in Coach 6), it is likely due to the type of video that is being imported. Please use a video conversion tool such as Any Video Converter to convert your video to a format suitable for Coach (e.g. from mp4 to avi). You can find a short guide to perform the conversion here.

Note: During the installation of Any Video Converter it is possible that some (unwanted) toolbars or other programs are also installed. These installations are optional and can be prevented by selecting “Customize Install” during installation and deselecting these additional programs.


The transportation method is decided in agreement with the buyer.

If articles are in stock, your delivery is made ready for shipment within 1 week after we receive your payment. If an ordered item is not in stock, it is placed in backorder. Backorders are sent for delivery as soon as they are available (and will be invoiced separately). International shipment may take up to several weeks, and CMA cannot guarantee a delivery date.


CMA is always open to your suggestions. They can be sent by email to We continuously strive to make our products match your needs.

Coach and other CMA products are distributed to a wide international audience. The initiative to translate the software and support materials comes from our international dealers. When a version in a different language is completed, these versions will become available online.

You can find instructions to reset the Author key in the online Coach help (search for ‘Author Key’).

The default key is 0000 (four times zero), but this may have been changed by any other user with Author access.

Yes, OS X (10.10 or newer) is supported starting from Coach 7. Note that while the Windows and OS X versions are almost identical, there are a few minor differences.
For Coach 6 there is only a Windows compatible version.


The Windows Coach 7.4 installation has been modified to not reset the Author key to the default value after update. This means that a file, which contains this Author key, will not be overwritten during Coach Installation. Unfortunately for installation of Coach 7.4 on some systems a direct upgrade (installation when an older version of Coach is installed) does not work correctly. In such situation, the file is deleted and not replaced by the new one, and you get an error message Cannot read Author key file. It may be missing or corrupt. There are two ways to solve this problem:
1. First uninstall the older version of Coach and after that install the new Coach 7.4, or
2. Run “Program and Features” repair.

This message appears when there is a program e.g. antivirus program, which blocks access to the User’s Documents folder. To solve this problem give Coach 7 access to this folder.



Coach 7 has the following system requirements:

For Windows

  • Windows 7 or newer;
  • Pentium 4 / 2,4 GHz processor or newer;
  • 300 MB hard disk space;
  • 512 MB RAM (1 GB recommended).

For Mac

  • OS X 10.11 El Capitan or newer;
  • 300 MB hard disk space;
  • 512 MB RAM (1 GB recommended).

More information about Coach 7 can be found in the installation guide and the dedicated Coach 7 page.

No, a special server-client network installation similar to what was available for Coach 6 is not possible for Coach 7. This method is no longer necessary. Coach can be installed safely to a shared network location, and users can start the application by opening the executable from there. At first launch, Coach will copy several configuration files to the user’s local data (e.g. CoachLocal.ini to AppData\Local\CMA\Coach7). You can edit Coach.ini from the installation folder to modify the paths to several important locations, such as the license file. See the Installation Guide for more information.

You can add multiple options to an MSI-installer. Consult the software Installation guide for more details. Use the options LICENSENAME and LICENSECODE to set these parameters for the entire installation process. When installing to a network location for shared access, the location of the license file can be fixed by modifying Coach.ini. It is still necessary to run Coach once after installation to generate the license files in the default location.

Make sure you do the following:

  1. Download and install the CMA certificate.
  2. Update the root certificates of Microsoft and VeriSign. This is usually not necessary if you use a fully updated version of Windows.

Please consult the Installation guide to troubleshoot any installation related problems. Follow the installation steps carefully. Use the ‘Ask a question’ form if the installation problems persist.


There can be a couple of reasons why Coach fails to communicate with VinciLab:

  • The VinciLab driver is not installed correctly on your computer. After a successful installation, VinciLab should be visible in the Windows Device Manager under Network adapters. If the driver wasn’t successfully installed, it can be installed manually in Device Manager by specifying the USB VinciLab driver setup files. Details of this procedure can be found in the VinciLab Users’ Guide.
  • The USB cable is not connected correctly. You have to connect the provided USB cable correctly and use the USB connector that is meant for communication, and not the USB connector meant for additional powering.
  • A computer firewall may cause communication problems (via USB or Wi-Fi). Make sure that the Coach executable (Coach32.exe in Coach 6, Coach7.exe in Coach 7) has permission to use the ip-address of VinciLab, and ports 22 and 1111 – 1116 are opened. If connected through USB, the VinciLab gets an ip-address in the range – For a wireless connection, the address depends on your network configuration. Please note that when using the USB cable, it may take a while before VinciLab gets its final ip-address.
  • Some anti-virus programs can block communication between Coach and VinciLab. Give Coach permission for such communication.

In general: if an attempt to connect VinciLab in Coach fails and you change the hardware settings in Coach, restart VinciLab and try again to connect.

There appears to be a problem with some (newer) sensors where the EEPROM cannot be read properly by the CLAB. A solution for this hardware problem is yet unknown. At the moment we advise you to manually select unrecognized sensors from the sensor library.

The €Lab interface is only powered through USB, which places a limitation to the maximum power consumption. This may also be dependent on the computer the interface is connected to. Some sensors needs more power (for example the Force sensor or the CO2 sensor) and when such a sensor is connected to €Lab and the USB port does not provide enough power then the sensor may not work properly or may not be automatically recognised by the Coach software. First select manually the sensor from the Coach Sensor Library and check if this solves the problem.



There is a hotfix available for Windows 7, Vista Windows Server 2008 R2, Windows Vista or Windows Server 2008, and a separate hotfix for Windows XP.
After installation of the hotfix use the Device Manager to uninstall the VinciLab driver while VinciLab remains connected to the computer via the USB cable. Then disconnect the USB cable from the computer and connect it again to use the new Microsoft RNDIS driver.

Wireless measurement is possible with the VinciLab and CLAB interfaces. The VinciLab is an independent datalogger that can be connected to a computer and Coach to exchange data. The CLAB is a datalogger to which a measurement program can be uploaded via Coach. The measurement itself can be carried out wirelessly and the data can be transferred to Coach at a later time.
In addition, a wireless interface is being developed that uses Bluetooth to communicate with a computer / mobile device (within a 10 meter range).

Measurement / analysis

In Coach 6 this is possible via Tools > Library Filter, where you can select which sensors and actuators should be visible in Coach.
In Coach 7 it is not possible to make your own selection from the entire sensor library.

No, but by displaying a Meter you are able to view the magnitude of a signal in real-time.

No, this is not possible. However, you can obtain more data points through interpolation. Use the option Process/Analyze > Smooth for this and choose ‘Spline’ combined with ‘Replace data’.

Every interface has a maximum number of data points that can be collected. If this maximum is reached, the measurement stops automatically, even if a longer measurement time was set.
The maximum is 16.380 points for CoachLab II, 32.760 points for older models of CoachLab II+, and 500.000 points for the newest CoachLab II+ models with updated firmware (and Coach 6.3 or newer). The number of data points that can be collected at sampling frequencies higher than 10 kHz is also limited. In this case, the internal data buffer of the interface cannot be emptied quickly enough and the measurement will stop once the buffer is full. For CoachLab II+ this corresponds to a maximum of 32.760 data points.

To gather more data points than the allowed maximum, the option Repeat from the Measurement settings can be used.

First check the measurement settings to verify that the correct time and unit have been entered. It is also possible that the length of the time-axis in a diagram is shorter than the measurement time. This makes the measurement look shorter than it actually is. Use the option ‘Zoom to fit’ to show the entire data range.


This is possible with the Simulate option. Here the value of a model parameter can be changed without having to edit the model continuously. To open the simulation window, right click in the Model window and choose “Simulate”.

When multiple events are required, it is usually more convenient to use the “Pulse” function. To use several events with the pulse function you need to introduce an auxiliary variable. Double click the variable and click on Formula and select ‘Use condition’. After that you can define your formula using the Pulse option.


We only accept payment by bank transfer.

Depending on your location, we will add appropriate shipping costs to your order.

Your order must be paid in advance via bank transfer. After receiving your online order, CMA will send you a proforma invoice. Your product will be shipped as soon as CMA receives your payment.


The blood pressure sensor BT17i (or 0377i) is a relatively complicated sensor for which the generation of a relevant graph is difficult to automate. This is because the procedure requires manual selection of relevant datapoints for each measurement. When using this sensor, please take note of the following:

  • The procedure for creating a envelope curve is extensively described in the sensors’s User Guide. Read the guide carefully and follow the described steps.
  • An example result in which the necessary processing steps have been carried out can be downloaded here. With this example, you know how the data is supposed to look.

There are a few tips that make the selection of relevant datapoints easier. In general, more datapoints means that the analysis can be done more accurately. You may, however, already achieve acceptable results using as little as 30 datapoints. Please take note of the following:

  • Make sure the measurement takes no longer than 40 to 60 seconds. This can be achieved by tweaking the pressure release valve to allow the cuff to deflate faster.
  • First select the interval in which you want to select the datapoints. This can be done by choosing “Range” instead of “Point-to-point” in the “Select/Remove Data” window. This considerably reduces the amount of points, making it easier to select relevant datapoints.
  • Maximize the selection screen by setting the window to full size using the icon in the top right corner of the window. The selection of points is easier when using a large window.

If you succeeded in selecting relevant datapoints and performing other processing steps, but did not get a envelope curve, please take note of the following:

  • It is possible that the range for p_trend was too small. The best results are acquired with a 40 – 140 mmHg range. When a smaller interval is used, part of the curve may be lost. Select datapoints over the entire interval. Especially the datapoints at 40 and 140 mmHg are important for the envelope curve.
  • The smoothing for p_pulse or p_trend may be wrong. In this case, the envelope curve is plotted over the entire range, but the actual envelope shape is not visible. This may be caused by insufficient/incomplete datapoint in one of the two measurements (either p_pulse or p_trend), for example when the selected points are in a smaller range or not distributed over the entire range. It is good practice to select always select the accompanying local minimum (p_trend) for every local maximum (p_pulse).

If a force is exerted on the sensor larger than the maximally allowed force (> 80 N), the internal mechanism will lose its elasticity. The sensor will no longer function properly afterwards and will have to be replaced.

Yes, this is normal behavior. The sensor uses a Hall-element which always gives a sinusoidal signal with an amplitude of approximately 2,5 mT on top of the measured signal. This is called “1/f noise”.

If a sensor shows a systematic error, or if the calibration does not conform to your desired application, you can modify the EEPROM-memory in the sensor. This is possible with the SensorCalibrate software that can be downloaded from our website (tab Utility Programs). The software only works in conjunction with a CoachLab II+ or ULAB. After modification of the sensor, the new calibration will be loaded automatically when the sensor is connected.

This information is for Coach 6 only.
If multiple identical sensors are present in the sensor palette, they will share the same calibration. The calibration of all sensors changes when a single calibration is modified.
To calibrate the sensors separately, do the following:

  1. Connect a sensor and drag its icon from position 1 on the sensor palette to an interface input. If the sensor is not present you have to choose it manually from the Sensor Library.
  2. Calibrate the sensor by right-clicking the icon and using, for example, ‘Set to Zero’ or ‘Set to Value’. After confirmation, the sensor icon is defined as a local sensor and no longer uses the calibration from the Coach Sensor Library. This applies to all icons located on the same sensor palette position.
  3. Connect a second sensor and drag its icon from position 2 on the sensor palette to another input of an interface. Again if the sensor is not present you have to choose it manually from the Sensor Library.
  4. Calibrate the second sensor and confirm. The sensor icon is now independent from the others and has a different calibration.

Of course you can do the same with a third and fourth sensor. Save your Activity or Result to store the calibrations. These are local activity calibrations and will be available only in this activity and not in standard Coach Sensor Library.

This may be caused by several factors:

  • The test subject is moving during the measurement. Let the test subject sit in a chair relaxed, with their arm lying at their side or on a table in front of him when data are being collected.
  • The used sampling frequency may influence the amount of detected noise. A sampling frequency of 50 Hz is high enough to measure an ECG signal but there will be not much noise detected. A sampling frequency of 200 Hz detects a lot more noise.
  • The sensor can also be used to measure electrical signals of contracted muscles. To obtain a nice ECG signal, it is therefore necessary that the muscles of the arms (and also other muscles) are as relaxed as possible.
  • For the older CMA ECG set, the electrodes are connected to the amplifier via 4 mm wires. Two parallel wires act as an antenna and catch noise from the power grid. Wrap the wires around each other a few times to get rid of this noise.

A possible cause for this phenomenon is a measurement frequency that is too high. The sampling frequency used in experiments with a motion detector is limited by the speed of sound in air (about 340 m/s): if a distance of 10 m is measured, the sound pulse takes about 59 ms to travel from the motion detector to an object and back. This means that if a sample frequency of more than 17 Hz is used, a new sound pulse is emitted before the previous one is received, leading to erratic readings. The maximal frequency is also limited by the conditions of the experiment. Typical sampling frequencies are: 1 m range – 40 Hz. 2 m to 6 m range – 25 Hz and 6 m to 10 m range – 10 Hz.

The sensor makes use of an electrochemical cell to determine the oxygen concentration. This cell will deteriorate over time, which limits the shelf-life of the sensor to 2 or 3 years. The sensor needs to be replaced after this period.

Yes, CMA supplies a CO2 to O2 Tee coupling piece (art. No. 07661) which fits the sampling bottle to which the two gas sensors can be connected.

When the sensor is collecting data, the intensity of its IR source is modulated (the sensor takes a reading about every 3 s). If the sampling frequency is set to a higher value, the CO2 readings will have some fluctuations (between readings taken when the IR source is on and the readings taken when the IR source is off).

The CO2 sensor can be calibrated using the calibration button on the sensor box. This button sets the reading of the sensor to a value around 400 ppm CO2 (the theoretical CO2 concentration value in fresh air).

  • Place the 250 mL sampling bottle delivered with your sensor in the air outside long enough to ensure that its content is replaced with fresh air.
  • While still outdoors, insert the sensor with the rubber stopper into the bottle. You can now take the bottle and the sensor to the location where the measurements will be performed.
  • Connect the CO2 sensor to an interface and let the sensor warm up by collecting data for at least 5 minutes.
  • When the readings stabilize use a paper clip or a ballpoint to press down the calibration button. After about 30 seconds, the reading should stabilize at a value around 400 ppm.

From a teacher we got a tip for checking the accuracy of the spirometer. The calibration can be controlled with two drain tubes of known content, pressed into each other and closed off. One tube section is filled with water, the other remains empty. Connect the spirometer to the empty tube at the closed side (spirometer 0378i or BT82i). Start a measurement and slide the empty tube into the water-filled tube section. The trapped air escapes through the spirometer. Because the volume of this air is known, the calibration of the spirometer can be established. Make sure that no water gets into the spirometer.

A spirometer measures the rate of air flow in liters per second. The total volume of air that has moved through the spirometer can be calculated by integrating the air flow rate as a function of time. Use the function Analyze/Process > Integral for this.
When the air flow data is converted to volume you may find an upward or downward trend in the volume data. You may apply a drift correction to the collected data in one of the following ways:

  • before you start your measurement set the signal measured by the sensor to zero by right clicking the sensor icon on the screen panel and choosing ‘Set to zero’, or
  • correct the data after the measurement is finished: determine a straight line through the drift by using the Function fit option and then use a formula to subtract the drift data from the measured sensor data


No, there will be no version of Coach 7 comparable to Coach 6 Studio MV. All functionality for modeling and video measurements are integrated into the complete Coach 7 package.

Yes, but be aware that the support for older versions of Coach will cease at some point in the future. We also cannot guarantee that Coach 6 remains functional with updates of your operation system.

There have been many small changes in Coach 7, compared to Coach 6. If you can no longer find a function that you used frequently, please contact us.

See for a full overview the ‘What is new ‘ PDF on the download page of Coach 7.
Some important improvements are: a new data table that makes working with multiple runs easier, using drag-and-drop to make graphs, automatic interface and sensor recognition, many graphical updates and usability improvements. The software has seen a large update of its code base to make it future proof.


Outside of the warranty period, CMA repairs selected interfaces and offers a special rate for sensor replacement. It is recommended to first contact your local dealer and report your problem, before you contact us directly. In many situations we can help to solve the problem, saving you shipping and repair costs.

Please check all packages on receipt. Verify that all your ordered products are present and are functioning properly. If you find any mistakes or problems contact CMA within 2 weeks. Claims for damage during shipment must be made within 24 hours from the receipt of goods.

Most CMA products carry a 24-months limited warranty. During this period, we will repair or replace the item if there is a material defect or defects due to poor workmanship. This warranty does not cover damage to the product caused by abuse or improper use. In case of doubt, please contact CMA.
The purchase invoice (or copy thereof) serves as warranty proof.

Webshop / ordering

  1. Log into the CMA webshop with your credentials (you will see your name at the top-right).
  2. Select the desired product and quantity and click ‘Order’.
  3. Once you have selected all products, go to you cart using the link ‘Cart/Checkout’.
  4. You will see the list of your ordered products. You can still make changes to quantities or remove products. The order is updated by clicking ‘Recalculate’. Click ‘Next’.
  5. Check the shipping address and press ‘Next’. Please note that we do not ship to PO boxes.
  6. The next screen provides information on payment. If you agree, press ‘Next’.
  7. The overview page displays all the information about your order. Please indicate that you have read the CMA Terms and Conditions and complete your order with the ‘Confirm Order’ button.
  8. You will receive a confirmation mail, followed by a final order confirmation with additional information about product availability or delivery.
  9. This final confirmation can be then checked for the correct delivery address, contact names etc. Within 24 hours the order can be changed if needed.

Currently it is not possible to request a quotation in the CMA online store directly. To request a quotation please send an email to CMA

You can browse the CMA online store in different ways: via Subject Areas followed by an educational sector/subject or via Category followed by a product type. If you know the CMA product number or name you can find it via the Search option.

Before you place an order, please check if your country has a local CMA dealer. If so, contact them for any purchases as CMA does not deliver directly to these countries. If not, first create a store account for the online CMA webshop. We do not share any of the information you provide with any other company, other than what is required to complete your orders. (i.e. delivery information to the courier). After receiving an on-line order CMA confirms the order by sending an order confirmation, which includes the shipping cost. The customer can check this order confirmation and modify it if needed. After the order confirmation has been accepted CMA will send a pro-forma invoice. Payment has to be done in advance, based on the pro-forma invoice. The products will be shipped as soon as the payment is received.
When ordering Coach software products you will receive a license letter with your license information and the installation code. The installation files can be downloaded from the CMA website.

If you lost your password for the online store, use the ‘Forgot your password?’ link to get your password reset.