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News
 
 

2 new models!

After power measurement and electronics, the SCOPIX III family has now been extended with specific features for testing field buses. With the SCOPIX BUS models, you can check the physical integrity of field buses to verify the signal transmission quality with 14 protocols: KNX-DALI-CAN-LIN-FLEXRAY-PROFIBUS-RS-ETHERNET …

Find out more...

2 new models!

After power measurement and electronics, the SCOPIX III family has now been extended with specific features for testing field buses. With the SCOPIX BUS models, you can check the physical integrity of field buses to verify the signal transmission quality with 14 protocols: KNX-DALI-CAN-LIN-FLEXRAY-PROFIBUS-RS-ETHERNET …

Find out more...

F.A.Q.
 
 

This area contains answers to your questions. Whatever the subject of your question, whether analysis or operation, our Technical Support team is available to answer it.


Q1: Can I purchase and download the various software options a few months after buying a SCOPIX oscilloscope?

A1: Yes, the various options can be downloaded at any time. These options include:

  • HX0028: Harmonics option
  • HX0029: Recorder option
  • HX0075: Power option
  • HX0077: 50-kpoint memory extension

Q2: Will future Probix accessories be compatible with SCOPIX III oscilloscopes?

A2: All the Probix accessories developed will be compatible with all the oscilloscopes in the SCOPIX range.


Q3: I want to view a pulse train with a central pulse which is wider than the others. How can I do this?
 

A3: The Scopix is equipped with sophisticated triggering functions. It is possible to trigger signal capture according to a pulse width.
In this way, if you want to capture your signal when a pulse with a defined width is detected, you have to use the "Pulse" triggering mode so that you can set the required pulse width and trigger your signal correctly.

Triggering on pulse

 

 

 

 

 

 

 


 Q4: I want to view a pulse train synchronized with another signal. How can I do this?

A4: The Scopix is equipped with sophisticated triggering functions. By causing a trigger delay after the synchronization signal, you can trigger on the first pulse train.

synchro pulse trigger pulse trigger synchronization


Q5: I want to trigger on a specific pulse. How can I do this?

A5: The Scopix is equipped with sophisticated triggering functions. It is thus possible to perform triggering according to the count of the number of events in order to achieve triggering on a specific edge.
When the count reaches the maximum defined, triggering will occur on the next edge.

pulse count triggering  pulse count triggering


 Q6: I want to buy an HX0034 AC/DC current clamp. What is its battery life in DC mode?

A6: A current clamp like the HX0034 contains internal electronics powered via the connection cable thanks to the Probix system. The battery life of this clamp therefore depends directly on the Scopix.


Q7: What can the FFT function be used for?

A7: FFT stands for Fast Fourier Transform. When this parameter is activated, the representation is frequency-based instead of time-based. In other words, the variable is no longer time, but frequency.
For example, measurement of an oscillator's distortion level or detection of a noise (audio) caused by a specific gear on a rotating machine. In both of these cases, the aim is to detect a sinusoidal signal with a lower amplitude than a dominant component. The best way of searching for this low-amplitude component is to use the frequency-based representation because it separates each component. This makes it easy to identify them, unlike the time-based representation in which they are mixed together.
For example, let us take the addition of two sine waves, one with an amplitude of 5 V at a frequency of 125 Hz, and the other with an amplitude of 0.5 V at 2,250 Hz.
The Math2 signal, in green, shows this representation. To determine the component at 2,250 Hz, the time-based representation is not very practical because of its amplitude.
If we change to frequency-based representation, the two components are separated. They are then simple to determine.

sine fft frequential fft


Q8: What is the difference between the linear and logarithmic scales?

A8: If we return to the previous example, we have a 5 V component and a 0.05 V component, giving a ratio of 100 between the two. If we display the FFT of this signal ion a linear scale, several choices are available: either the 250 Hz component is nearly impossible to see or the amplitude of the main component is truncated, unless the graphic is large enough to display both correctly.
If we use a logarithmic scale, it will compress the high-amplitude component and dilate the low-amplitude component, thus enabling them to be shown on the same graphic while allowing measurements. The logarithmic scale has its own unit: the Bel, more commonly used in its "tenth" form, the decibel (dB).
Db ratio = 20*log(voltage).

linear scale

 

Linear scale: the component at 2,250 Hz cannot be seen.

 

 

 

 

logarithmic scale

 

Logarithmic scale: the two components are easily identifiable and measurable.
For a voltage ratio of 100, there are 40dB more, as shown on the FFT graphic opposite.

 

 

 


 

Q9: What are the different possible uses of the files recorded by the Scopix?

Q9: The ".trc" trace files in the Scope or Meter mode are designed either to be re-opened in the oscilloscope via the "recall" function available in the "Memory" / "Trace" function, or to display the trace in Sx-Metro. To do this, select "File Manager" / "Open" and then select the ".trc" file to be opened.
These files can also be exported into Excel from Sx-Metro.

The ".rec" recording files in Recorder mode can be recalled by the oscilloscope for display later on or opened in Sx-Metro, just like the trace files. It is also possible to export them into Excel using Sx-Metro.

The ".txt" text files are designed to be imported directly into Excel. The import method is described in the explanatory datasheet on "Data processing on computer". They cannot be used in Sx-Metro.

The ".cfg" configuration files contain the oscilloscope configuration data: the oscilloscope's mode (Scope/Meter/Recorder/Analyser) and the various data for each channel: sensitivities, coupling, bandwidth limitation. These data are intended to be opened in Sx-Metro or used to restore a configuration in the oscilloscope.

The ".fct" mathematical function files contain a recorded mathematical function. These files can only be opened with the oscilloscope in the Math menu.

There are various file formats for screenshots.
The .prn, .pcl and .eps files are print files, which means they contain binary data formatted to be transmitted to a printer. This file format is for network printers.
The .gif and .bmp files are image files which can be imported onto your computer for display or for incorporation in a document. They are also used with Virtual Printer to enable networked printing via a computer.


Q10: Can I display the amplitude variations and frequency variations over time (AM/FM signal for example) with my Scopix?

A10: The Scopix has two display modes which allow you to display the signal variations over time. The first is "envelope" mode. This mode displays the minimum and on the Y axis of each sample of the signal.
The second is the "total mode". It operates similarly to the envelope mode, but it stores the different acquisitions and displays the most recent in a brighter colour to distinguish them.
These two display modes allow effective analysis of signals that vary over time.

AM envelope display


"Envelope" display with AM modulation

 

 

 

 

FM total display

 

 

"Total" display with FM modulation

 

 

 


 Q11: Why adjust the vertical scale manually?

A11: By adjusting the vertical scale manually, you can obtain a trace as required with the amplitude that you want. In the menu bar at the top of the screen, the vertical scale setting can be found in "Vert / chx / Sensitivity-Coupling" in Scope/Recorder/Analyser modes or "Vert / chx /Vertical scale" in Meter mode (where x represents the number of the channel to be modified).

vertical scale

 

 

 

 

 

It is also possible to adjust the amplitude using the buttons.

vertical scale

 

 

 

 

You can also adjust the horizontal sensitivity by double-clicking on channel CH1 and then indicating the required sensitivity.

vertical scale vertical scale


Q12: Why expand the on-screen traces horizontally?

A12 : By expanding the on-screen traces horizontally; you can observe any phenomena occurring over small time variations, without having to totally recalibrate the oscilloscope.horizontal zoom

 

To enlarge the traces/harmonics on the screen, simply press the ZOOM ON/OFF button.

 

 

 

Another effective way of zooming on a part of the screen is to use the "touch zoom". This is possible by tracing the part to which the zoom must be applied.
The finger shapes the part to be zoomed. To do this, slide your finger as shown below to obtain a zoomed image:

horizontal zoom horizontal zoom


Q13: Why adjust the vertical scale in Multimeter mode?

A13: The choice of the measurement range depends on several parameters. That is why you need to adjust the vertical scale of:
• the measurement type selected:

  • Amplitude (available on all channels),
  • Ohmmeter,
  • Continuity,
  • Capacitance meter,
  • Pt100 temperature probe

• the Probix probe connected to the input,
• the parameters in the "Vertical Scale" menu (if the parameters have been modified since connection of the Probix probe).
In the menu bar at the top of the screen, use the menu Vert / ch x (x = 1/2/3/4) / Sensitivity- Coupling to display the adjustment window. Then enter the required values in Range, while keeping the Autorange active.

meter vertical rangemeter mode vertical range

In the ranges, it is also possible to add filters. Two are available: one 625 Hz filter and one 5 kHz filter (if the 625 Hz filter is activated, the 5 kHz filter is activated too).
These filters are used to remove the disturbances from the high frequencies of the signal to obtain a signal without too much disturbance to provide accurate measurements which are easy to understand.
To demonstrate how useful and powerful these filters can be, we injected a frequency-modulated signal on the inputs of a Scopix oscilloscope, initially in Scope mode:
a 90 Hz / 10 Vpp signal and a 5kHz / 10 Vpp signal which combine to give a modulated signal:

 meter vertical range

 

 

 

 

 

Once we have observed the signal in Scope mode, we must switch to Meter mode so that the instrument indicates the RMS voltage which it has measured. With a 10 Vpp signal, an RMS value of 3.53 V should be obtained, but the Meter mode measures an RMS value of 3.97 V because of the 5 kHz disturbance signal.

meter vertical range

To solve this problem, we can activate the 625 Hz filter which also activates the 5 kHz signal. The RMS value of the signal voltage measured is then 3.59 V.

meter vertical range

 

 

 

 

 

The filters have thus eliminated the disturbance signal. The filters are particularly useful in cases like this. The higher the carrier frequency, the greater the efficiency of the filtering. For example, for a carrier frequency of 115 kHz, we obtain an RMS voltage value of 3.57 V.

Another possible application for showing the effectiveness of the filters is an application involving a PWM variable speed drive. A test with a pulse-width modulator was therefore performed:

vertical meter



 

 

 

When we are using pulse-width modulation, the RMS value of the voltage as measured by the Meter mode is incorrect if the filters are not active. Indeed, the frequency measurement is not correct, causing an error on the RMS voltage value.

vertical meter

 

 

 

 

 

This phenomenon is due to the Meter mode which is not capable of following the frequency value proposed because it is drawn alternately towards 10 kHz and 20/60 Hz.vertical meter

 

 

 

 

 

To solve this problem, we must activate the Meter mode's 625 Hz filter which automatically activates the 5 kHz filter. The PWM is then transformed into a sinusoidal with a single frequency, making it possible to perform the measurement. vertical meter

 

 

 

 

 

The frequency value measured is then correct with the filter. We can conclude from this that the RMS value of the voltage is accurate because the voltage depends on the frequency in a PWM variable speed drive. However, this voltage value is still not optimized. For greater accuracy, we need to use a Probix HX0093 probe.
The Probix HX0093 has a built-in analogue filter which provides additional filtering in order to obtain the best possible result.
In Scope mode, as it is connected to the PWM variable speed drive without an internal Scopix filter, we obtain a sine wave directly thanks to the Probix filter:

vertical meter

 

 

 

 

 

Now that we are in Meter mode with all the possible filters, we obtain a precise frequency value, so the RMS voltage value is more accurate than before.

vertical meter

 

 

 

 

 

 


Q14: Why switch to XY mode? (Scope)

A14: The XY mode is used to deactivate the time-based sweep so that we can display channel 2 vertically as a function of channel 1 (horizontal). This function can be used for example to model the Hysteresis curve of a ferromagnetic material, allowing us to make comparisons between two signals.
To switch to XY mode, you must use the Display menu at the top of the screen and select the function with the check box.

Scope xy mode

xy modexy mode

 

xy modemode xy

 

 

 

 

 

It is possible to use more advanced operations capable of tracing a math function according to a waveform of reference or to trace several channels on the Y axis as a function of a single channel on the X axis.

One quite well-known example of XY mode use involves Lissajous figures.
These figures can be used to compare two signals. With the oscilloscope in XY mode, one signals must be injected via the X input and the other must be injected via the Y input.
Then, depending on the nature of the curves obtained, we can deduce the phase existing between two signals (when they are at the same frequency) or determine the ratio between their frequencies.

lissajous figure

The curve of the signals with the same frequency forms an ellipse. Examination of the figure shows that the phase offset between the two signal is such that:
sin𝜑 = ℎ𝐻
For phases equal to 0 or 180°, the ellipse degenerates into a straight line.
This method allows measurement of the relative phases between two signals.

 

 

By sending two signals with the same frequency (300 Hz and 20 Vpp) to the oscilloscope by means of two LF generators and by using the XY function, we obtain an ellipse:

scope ellipsescope ellipse

To find out the phase offset between the two signals, all we need to do is perform the division h/H
sin𝜑 = ℎ𝐻 = 1,5𝑑𝑖𝑣4𝑑𝑖𝑣
sin−1􁉀1,54􁉁 = 𝜑 𝜑=22 °
The phases of the two signals are offset by 22 degrees.


Q15: How can I obtain a Scopix option and validate it?

A15: The basic version of the Scopix delivered does not include all the options. Instead, it is up to users to choose the options which will be useful for them when they purchase their instrument. However, it is still possible to add an option later on (Attention: if you have a Scopix Bus, this is not possible!).
To add an option, you need to contact a Chauvin Arnoux sales representative so that they can send you the form which you must then complete and return. In this form, you are asked to indicate the type of instrument to which you want to add the option, its serial number, your contact details and how you wish to receive the code in order to activate the option (by post, fax or email).
Part of the form to be filled in:

scopix option order form

 

 

 

 

 

 

 

 

 

 

 

 

 

Once you have the code, simply enter it in the Scopix by using the menu ?/Options

scopix option order

option order form

Enter the code in the empty "New option" fields". You must then restart the instrument for the modification to take effect. 

option order form

 

 

 

 

 

 

Attention: if you extend the memory from 2,500 to 50,000 points, all the traces recorded in the 2,500-point memory will be deleted.
To avoid bugs, you are strongly advised to reset the instrument to the factory configuration. To do this, use the menu Memory/Setup/Recall, and then Default Setup followed by copy.

scopix option order formscopix option order form

You now have an instrument with a new option.


Q16: Why carry out cursor and phase measurements (Scope)?

A16: The cursor and phase measurements leave the choice of the measurements up to the users. If users wish to perform a specific measurement or simply check the information provided by the automatic measurements, they can use manual measurements.
To perform manual cursor measurements in Scope mode, use the menu Measure / Manual measurements (dt, dv). Then all you need to do is position the cursors according to what you want to measure.

phase cursorphase cursor

To perform manual phase measurements in Scope mode, you have to use the menu Measure / Manual phase measurements. Then all you have to do is position the cursors according to what you want to measure.

phase cursorphase cursor

When the measurement involves two signals, the cursors are assigned to one of the two signals. It is not possible to perform cursor measurements between several signals. There must be a reference for each of the cursors to avoid erroneous measurements.

phase cursor

 

 

 

 

 

For example, in this test, we transmit two 100 Hz signals. We check the period for the signal on channel 1 and we obtain the same value found with the automatic measurements.

scope phase cursor

 

 

 

 

 

For manual phase measurements between two signals, cursors 1 and 2 must be separated by one period. The oscilloscope provides useful assistance for this operation. The φ cursor must be positioned one period before the first period cursor. In this configuration, with a reference signal on channel 1, the manual phase measurement system allows a phase offset of -180° between the two signals displayed.


Q17: Why use a Scopix Bus and what upgrades are possible?

A17: The Scopix Bus has been developed specially to provide bus analysis as well as the Scope, Meter and Recorder modes. The Analyser mode has been replaced by the Bus mode (harmonic analysis is not possible with a Scopix Bus unless you use the FFT option).
It was not possible to perform bus analysis before this version of Scopix Bus. You can now use this function to perform the electrical measurements required to assess the integrity of the field bus, i.e. the operation of the physical layer (electrical specifications, synchronization, etc.), in compliance with the applicable standards.
This mode is particularly simple to use because three steps are all it takes to check the integrity of a field bus. The result is also displayed explicitly by coloured icons.
This instrument is capable of analysing 14 buses (KNX, DALI, CAN, LIN, FlexRay, AS-i, Profibus, RS-485, RS-232, Ethernet, etc.). It has 21 configurations and various protocols (IP, TCP, Modbus, Profinet, etc.) are already integrated.
The Scopix Bus models offer help after connection according to the bus to be tested, by proposing the corresponding electrical diagram. It is also possible to modify certain buses and to create new buses or configurations with the SX-BUS software.
To modify a bus, you must first switch to Analyser mode and then choose a default bus (e.g. CAN HS 1Mbps) before using the menu Measure/Limits:

scopix bus limitsscopix bus limits

To change a default parameter, click twice on one of the Min, Max or Warning values to open a digital keyboard and then enter the required parameters.

scopix bus limits

 

 

 

 

 

Once all the parameters have been filled in, click on OK to jump to the Save window.
Save the parameters of this modified bus by entering a file name and then clicking on the Copy button.

scopix bus limits

 

 

 

 

 

 

Once you have saved the modified bus, press the BUS button on the instrument to select this modified bus.

scopix bus limits

 

You can then start bus analysis with your parameters by pressing the DIAG button on the instrument's front panel.

 

 

 

 


Q18: Why create MATH functions and how are they used? (Scope and Recorder modes)

A18: The mathematical functions are used to perform operations between different signals, such as multiplying the signals on channel 1 and on channel 2. There are many possibilities, depending on the type of application.

Before creating a function, you need to know the scaling functions Divv(x) and Divh(x). These functions will allow you to format your traces resulting from a mathematical function.
Divv(1) represents one vertical division, while Divh(1) represents one horizontal division. To use Divv, you must in general multiply it by the signal, which will therefore be equal to x division(s) for a value of 1.
To use Divh, you must:
• either subtract it from t to create an offset,
• or divide t by Divh(x) to scale it, with x to be determined according to the period of the signal.
Math2 = Divv (1); Math3 = -Divv (1)*Step (T-Divh (4))

fonction maths

 

 

 

 

 

To access these Math functions, go to the menu bar at the top of the screen and use the menu "Vert / math x (x = 1/2/3/4) / Function definition" to open the function definition window.

math functionmath functionmath function

 

Several simple functions are available, including:

Square signal
math1= (sin (pi*t/Divh(2) +sin (3*pi*t/Divh(2))/3 +sin (5*pi*t/Divh(2))/5 +sin (7*pi*t/Divh(2))/7)*Divv(4)

math function

 Sawtooth signal
math1= (sin (pi*t/Divh(2) –sin (3*pi*t/Divh(2))/3) +sin (5*pi*t/Divh(2))/5)-sin (7*pi*t/Divh(2))/)*Divv(4)

math function

Cloverleaf
Math1 = Divv(1)*(2*cos(t/Divh (0.1)) +2*cos (2*t/Divh (0.1))); Math2 = Divv(1)*(2*sin(t/Divh (0.1))-2*sin (2*t/Divh (0.1))); You must then activate the XY mode:

colverleaf math function


 

 

 

 

 


Ask your question!

 

This area contains answers to your questions. Whatever the subject of your question, whether analysis or operation, our Technical Support team is available to answer it.


Q1: Can I purchase and download the various software options a few months after buying a SCOPIX oscilloscope?

A1: Yes, the various options can be downloaded at any time. These options include:

  • HX0028: Harmonics option
  • HX0029: Recorder option
  • HX0075: Power option
  • HX0077: 50-kpoint memory extension

Q2: Will future Probix accessories be compatible with SCOPIX III oscilloscopes?

A2: All the Probix accessories developed will be compatible with all the oscilloscopes in the SCOPIX range.


Q3: I want to view a pulse train with a central pulse which is wider than the others. How can I do this?
 

A3: The Scopix is equipped with sophisticated triggering functions. It is possible to trigger signal capture according to a pulse width.
In this way, if you want to capture your signal when a pulse with a defined width is detected, you have to use the "Pulse" triggering mode so that you can set the required pulse width and trigger your signal correctly.

Triggering on pulse

 

 

 

 

 

 

 


 Q4: I want to view a pulse train synchronized with another signal. How can I do this?

A4: The Scopix is equipped with sophisticated triggering functions. By causing a trigger delay after the synchronization signal, you can trigger on the first pulse train.

synchro pulse trigger pulse trigger synchronization


Q5: I want to trigger on a specific pulse. How can I do this?

A5: The Scopix is equipped with sophisticated triggering functions. It is thus possible to perform triggering according to the count of the number of events in order to achieve triggering on a specific edge.
When the count reaches the maximum defined, triggering will occur on the next edge.

pulse count triggering  pulse count triggering


 Q6: I want to buy an HX0034 AC/DC current clamp. What is its battery life in DC mode?

A6: A current clamp like the HX0034 contains internal electronics powered via the connection cable thanks to the Probix system. The battery life of this clamp therefore depends directly on the Scopix.


Q7: What can the FFT function be used for?

A7: FFT stands for Fast Fourier Transform. When this parameter is activated, the representation is frequency-based instead of time-based. In other words, the variable is no longer time, but frequency.
For example, measurement of an oscillator's distortion level or detection of a noise (audio) caused by a specific gear on a rotating machine. In both of these cases, the aim is to detect a sinusoidal signal with a lower amplitude than a dominant component. The best way of searching for this low-amplitude component is to use the frequency-based representation because it separates each component. This makes it easy to identify them, unlike the time-based representation in which they are mixed together.
For example, let us take the addition of two sine waves, one with an amplitude of 5 V at a frequency of 125 Hz, and the other with an amplitude of 0.5 V at 2,250 Hz.
The Math2 signal, in green, shows this representation. To determine the component at 2,250 Hz, the time-based representation is not very practical because of its amplitude.
If we change to frequency-based representation, the two components are separated. They are then simple to determine.

sine fft frequential fft


Q8: What is the difference between the linear and logarithmic scales?

A8: If we return to the previous example, we have a 5 V component and a 0.05 V component, giving a ratio of 100 between the two. If we display the FFT of this signal ion a linear scale, several choices are available: either the 250 Hz component is nearly impossible to see or the amplitude of the main component is truncated, unless the graphic is large enough to display both correctly.
If we use a logarithmic scale, it will compress the high-amplitude component and dilate the low-amplitude component, thus enabling them to be shown on the same graphic while allowing measurements. The logarithmic scale has its own unit: the Bel, more commonly used in its "tenth" form, the decibel (dB).
Db ratio = 20*log(voltage).

linear scale

 

Linear scale: the component at 2,250 Hz cannot be seen.

 

 

 

 

logarithmic scale

 

Logarithmic scale: the two components are easily identifiable and measurable.
For a voltage ratio of 100, there are 40dB more, as shown on the FFT graphic opposite.

 

 

 


 

Q9: What are the different possible uses of the files recorded by the Scopix?

Q9: The ".trc" trace files in the Scope or Meter mode are designed either to be re-opened in the oscilloscope via the "recall" function available in the "Memory" / "Trace" function, or to display the trace in Sx-Metro. To do this, select "File Manager" / "Open" and then select the ".trc" file to be opened.
These files can also be exported into Excel from Sx-Metro.

The ".rec" recording files in Recorder mode can be recalled by the oscilloscope for display later on or opened in Sx-Metro, just like the trace files. It is also possible to export them into Excel using Sx-Metro.

The ".txt" text files are designed to be imported directly into Excel. The import method is described in the explanatory datasheet on "Data processing on computer". They cannot be used in Sx-Metro.

The ".cfg" configuration files contain the oscilloscope configuration data: the oscilloscope's mode (Scope/Meter/Recorder/Analyser) and the various data for each channel: sensitivities, coupling, bandwidth limitation. These data are intended to be opened in Sx-Metro or used to restore a configuration in the oscilloscope.

The ".fct" mathematical function files contain a recorded mathematical function. These files can only be opened with the oscilloscope in the Math menu.

There are various file formats for screenshots.
The .prn, .pcl and .eps files are print files, which means they contain binary data formatted to be transmitted to a printer. This file format is for network printers.
The .gif and .bmp files are image files which can be imported onto your computer for display or for incorporation in a document. They are also used with Virtual Printer to enable networked printing via a computer.


Q10: Can I display the amplitude variations and frequency variations over time (AM/FM signal for example) with my Scopix?

A10: The Scopix has two display modes which allow you to display the signal variations over time. The first is "envelope" mode. This mode displays the minimum and on the Y axis of each sample of the signal.
The second is the "total mode". It operates similarly to the envelope mode, but it stores the different acquisitions and displays the most recent in a brighter colour to distinguish them.
These two display modes allow effective analysis of signals that vary over time.

AM envelope display


"Envelope" display with AM modulation

 

 

 

 

FM total display

 

 

"Total" display with FM modulation

 

 

 


 Q11: Why adjust the vertical scale manually?

A11: By adjusting the vertical scale manually, you can obtain a trace as required with the amplitude that you want. In the menu bar at the top of the screen, the vertical scale setting can be found in "Vert / chx / Sensitivity-Coupling" in Scope/Recorder/Analyser modes or "Vert / chx /Vertical scale" in Meter mode (where x represents the number of the channel to be modified).

vertical scale

 

 

 

 

 

It is also possible to adjust the amplitude using the buttons.

vertical scale

 

 

 

 

You can also adjust the horizontal sensitivity by double-clicking on channel CH1 and then indicating the required sensitivity.

vertical scale vertical scale


Q12: Why expand the on-screen traces horizontally?

A12 : By expanding the on-screen traces horizontally; you can observe any phenomena occurring over small time variations, without having to totally recalibrate the oscilloscope.horizontal zoom

 

To enlarge the traces/harmonics on the screen, simply press the ZOOM ON/OFF button.

 

 

 

Another effective way of zooming on a part of the screen is to use the "touch zoom". This is possible by tracing the part to which the zoom must be applied.
The finger shapes the part to be zoomed. To do this, slide your finger as shown below to obtain a zoomed image:

horizontal zoom horizontal zoom


Q13: Why adjust the vertical scale in Multimeter mode?

A13: The choice of the measurement range depends on several parameters. That is why you need to adjust the vertical scale of:
• the measurement type selected:

  • Amplitude (available on all channels),
  • Ohmmeter,
  • Continuity,
  • Capacitance meter,
  • Pt100 temperature probe

• the Probix probe connected to the input,
• the parameters in the "Vertical Scale" menu (if the parameters have been modified since connection of the Probix probe).
In the menu bar at the top of the screen, use the menu Vert / ch x (x = 1/2/3/4) / Sensitivity- Coupling to display the adjustment window. Then enter the required values in Range, while keeping the Autorange active.

meter vertical rangemeter mode vertical range

In the ranges, it is also possible to add filters. Two are available: one 625 Hz filter and one 5 kHz filter (if the 625 Hz filter is activated, the 5 kHz filter is activated too).
These filters are used to remove the disturbances from the high frequencies of the signal to obtain a signal without too much disturbance to provide accurate measurements which are easy to understand.
To demonstrate how useful and powerful these filters can be, we injected a frequency-modulated signal on the inputs of a Scopix oscilloscope, initially in Scope mode:
a 90 Hz / 10 Vpp signal and a 5kHz / 10 Vpp signal which combine to give a modulated signal:

 meter vertical range

 

 

 

 

 

Once we have observed the signal in Scope mode, we must switch to Meter mode so that the instrument indicates the RMS voltage which it has measured. With a 10 Vpp signal, an RMS value of 3.53 V should be obtained, but the Meter mode measures an RMS value of 3.97 V because of the 5 kHz disturbance signal.

meter vertical range

To solve this problem, we can activate the 625 Hz filter which also activates the 5 kHz signal. The RMS value of the signal voltage measured is then 3.59 V.

meter vertical range

 

 

 

 

 

The filters have thus eliminated the disturbance signal. The filters are particularly useful in cases like this. The higher the carrier frequency, the greater the efficiency of the filtering. For example, for a carrier frequency of 115 kHz, we obtain an RMS voltage value of 3.57 V.

Another possible application for showing the effectiveness of the filters is an application involving a PWM variable speed drive. A test with a pulse-width modulator was therefore performed:

vertical meter



 

 

 

When we are using pulse-width modulation, the RMS value of the voltage as measured by the Meter mode is incorrect if the filters are not active. Indeed, the frequency measurement is not correct, causing an error on the RMS voltage value.

vertical meter

 

 

 

 

 

This phenomenon is due to the Meter mode which is not capable of following the frequency value proposed because it is drawn alternately towards 10 kHz and 20/60 Hz.vertical meter

 

 

 

 

 

To solve this problem, we must activate the Meter mode's 625 Hz filter which automatically activates the 5 kHz filter. The PWM is then transformed into a sinusoidal with a single frequency, making it possible to perform the measurement. vertical meter

 

 

 

 

 

The frequency value measured is then correct with the filter. We can conclude from this that the RMS value of the voltage is accurate because the voltage depends on the frequency in a PWM variable speed drive. However, this voltage value is still not optimized. For greater accuracy, we need to use a Probix HX0093 probe.
The Probix HX0093 has a built-in analogue filter which provides additional filtering in order to obtain the best possible result.
In Scope mode, as it is connected to the PWM variable speed drive without an internal Scopix filter, we obtain a sine wave directly thanks to the Probix filter:

vertical meter

 

 

 

 

 

Now that we are in Meter mode with all the possible filters, we obtain a precise frequency value, so the RMS voltage value is more accurate than before.

vertical meter

 

 

 

 

 

 


Q14: Why switch to XY mode? (Scope)

A14: The XY mode is used to deactivate the time-based sweep so that we can display channel 2 vertically as a function of channel 1 (horizontal). This function can be used for example to model the Hysteresis curve of a ferromagnetic material, allowing us to make comparisons between two signals.
To switch to XY mode, you must use the Display menu at the top of the screen and select the function with the check box.

Scope xy mode

xy modexy mode

 

xy modemode xy

 

 

 

 

 

It is possible to use more advanced operations capable of tracing a math function according to a waveform of reference or to trace several channels on the Y axis as a function of a single channel on the X axis.

One quite well-known example of XY mode use involves Lissajous figures.
These figures can be used to compare two signals. With the oscilloscope in XY mode, one signals must be injected via the X input and the other must be injected via the Y input.
Then, depending on the nature of the curves obtained, we can deduce the phase existing between two signals (when they are at the same frequency) or determine the ratio between their frequencies.

lissajous figure

The curve of the signals with the same frequency forms an ellipse. Examination of the figure shows that the phase offset between the two signal is such that:
sin𝜑 = ℎ𝐻
For phases equal to 0 or 180°, the ellipse degenerates into a straight line.
This method allows measurement of the relative phases between two signals.

 

 

By sending two signals with the same frequency (300 Hz and 20 Vpp) to the oscilloscope by means of two LF generators and by using the XY function, we obtain an ellipse:

scope ellipsescope ellipse

To find out the phase offset between the two signals, all we need to do is perform the division h/H
sin𝜑 = ℎ𝐻 = 1,5𝑑𝑖𝑣4𝑑𝑖𝑣
sin−1􁉀1,54􁉁 = 𝜑 𝜑=22 °
The phases of the two signals are offset by 22 degrees.


Q15: How can I obtain a Scopix option and validate it?

A15: The basic version of the Scopix delivered does not include all the options. Instead, it is up to users to choose the options which will be useful for them when they purchase their instrument. However, it is still possible to add an option later on (Attention: if you have a Scopix Bus, this is not possible!).
To add an option, you need to contact a Chauvin Arnoux sales representative so that they can send you the form which you must then complete and return. In this form, you are asked to indicate the type of instrument to which you want to add the option, its serial number, your contact details and how you wish to receive the code in order to activate the option (by post, fax or email).
Part of the form to be filled in:

scopix option order form

 

 

 

 

 

 

 

 

 

 

 

 

 

Once you have the code, simply enter it in the Scopix by using the menu ?/Options

scopix option order

option order form

Enter the code in the empty "New option" fields". You must then restart the instrument for the modification to take effect. 

option order form

 

 

 

 

 

 

Attention: if you extend the memory from 2,500 to 50,000 points, all the traces recorded in the 2,500-point memory will be deleted.
To avoid bugs, you are strongly advised to reset the instrument to the factory configuration. To do this, use the menu Memory/Setup/Recall, and then Default Setup followed by copy.

scopix option order formscopix option order form

You now have an instrument with a new option.


Q16: Why carry out cursor and phase measurements (Scope)?

A16: The cursor and phase measurements leave the choice of the measurements up to the users. If users wish to perform a specific measurement or simply check the information provided by the automatic measurements, they can use manual measurements.
To perform manual cursor measurements in Scope mode, use the menu Measure / Manual measurements (dt, dv). Then all you need to do is position the cursors according to what you want to measure.

phase cursorphase cursor

To perform manual phase measurements in Scope mode, you have to use the menu Measure / Manual phase measurements. Then all you have to do is position the cursors according to what you want to measure.

phase cursorphase cursor

When the measurement involves two signals, the cursors are assigned to one of the two signals. It is not possible to perform cursor measurements between several signals. There must be a reference for each of the cursors to avoid erroneous measurements.

phase cursor

 

 

 

 

 

For example, in this test, we transmit two 100 Hz signals. We check the period for the signal on channel 1 and we obtain the same value found with the automatic measurements.

scope phase cursor

 

 

 

 

 

For manual phase measurements between two signals, cursors 1 and 2 must be separated by one period. The oscilloscope provides useful assistance for this operation. The φ cursor must be positioned one period before the first period cursor. In this configuration, with a reference signal on channel 1, the manual phase measurement system allows a phase offset of -180° between the two signals displayed.


Q17: Why use a Scopix Bus and what upgrades are possible?

A17: The Scopix Bus has been developed specially to provide bus analysis as well as the Scope, Meter and Recorder modes. The Analyser mode has been replaced by the Bus mode (harmonic analysis is not possible with a Scopix Bus unless you use the FFT option).
It was not possible to perform bus analysis before this version of Scopix Bus. You can now use this function to perform the electrical measurements required to assess the integrity of the field bus, i.e. the operation of the physical layer (electrical specifications, synchronization, etc.), in compliance with the applicable standards.
This mode is particularly simple to use because three steps are all it takes to check the integrity of a field bus. The result is also displayed explicitly by coloured icons.
This instrument is capable of analysing 14 buses (KNX, DALI, CAN, LIN, FlexRay, AS-i, Profibus, RS-485, RS-232, Ethernet, etc.). It has 21 configurations and various protocols (IP, TCP, Modbus, Profinet, etc.) are already integrated.
The Scopix Bus models offer help after connection according to the bus to be tested, by proposing the corresponding electrical diagram. It is also possible to modify certain buses and to create new buses or configurations with the SX-BUS software.
To modify a bus, you must first switch to Analyser mode and then choose a default bus (e.g. CAN HS 1Mbps) before using the menu Measure/Limits:

scopix bus limitsscopix bus limits

To change a default parameter, click twice on one of the Min, Max or Warning values to open a digital keyboard and then enter the required parameters.

scopix bus limits

 

 

 

 

 

Once all the parameters have been filled in, click on OK to jump to the Save window.
Save the parameters of this modified bus by entering a file name and then clicking on the Copy button.

scopix bus limits

 

 

 

 

 

 

Once you have saved the modified bus, press the BUS button on the instrument to select this modified bus.

scopix bus limits

 

You can then start bus analysis with your parameters by pressing the DIAG button on the instrument's front panel.

 

 

 

 


Q18: Why create MATH functions and how are they used? (Scope and Recorder modes)

A18: The mathematical functions are used to perform operations between different signals, such as multiplying the signals on channel 1 and on channel 2. There are many possibilities, depending on the type of application.

Before creating a function, you need to know the scaling functions Divv(x) and Divh(x). These functions will allow you to format your traces resulting from a mathematical function.
Divv(1) represents one vertical division, while Divh(1) represents one horizontal division. To use Divv, you must in general multiply it by the signal, which will therefore be equal to x division(s) for a value of 1.
To use Divh, you must:
• either subtract it from t to create an offset,
• or divide t by Divh(x) to scale it, with x to be determined according to the period of the signal.
Math2 = Divv (1); Math3 = -Divv (1)*Step (T-Divh (4))

fonction maths

 

 

 

 

 

To access these Math functions, go to the menu bar at the top of the screen and use the menu "Vert / math x (x = 1/2/3/4) / Function definition" to open the function definition window.

math functionmath functionmath function

 

Several simple functions are available, including:

Square signal
math1= (sin (pi*t/Divh(2) +sin (3*pi*t/Divh(2))/3 +sin (5*pi*t/Divh(2))/5 +sin (7*pi*t/Divh(2))/7)*Divv(4)

math function

 Sawtooth signal
math1= (sin (pi*t/Divh(2) –sin (3*pi*t/Divh(2))/3) +sin (5*pi*t/Divh(2))/5)-sin (7*pi*t/Divh(2))/)*Divv(4)

math function

Cloverleaf
Math1 = Divv(1)*(2*cos(t/Divh (0.1)) +2*cos (2*t/Divh (0.1))); Math2 = Divv(1)*(2*sin(t/Divh (0.1))-2*sin (2*t/Divh (0.1))); You must then activate the XY mode:

colverleaf math function


 

 

 

 

 


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