9225 and 9227 Module Constant phase shift (Drift)

Similar Questions

• Align the two signals and measure the Phase Shift

  Hello

  I do an experiment in which I use the NI USB-6221 DAQ card. The jury is able to make 250 k samples/second. I want to measure two voltages in a circuit and find the phase shift between them at frequencies between 1 and 10000. First I ouputted a wave sinusoidal frequency variable through the Commission and applied to a test circuit. Then I used the Board to measure the two tensions consecutively (thus reducing the maximum sampling frequency at 125 k). I used the signals align VI and measured the two phases and then calculates the phase shift (VI attached in Phase 1). It worked well for the test circuit I built in which the phase shift went way logarithmique.20 degrees ~84.5 degrees and then stabilized. At frequencies above 5 000 Hz phase shift must have remained constant, but it varies more or less 1 degree. When the phase shift is 84.5 degrees, present a degree of variability is not particularly explicit. When I asked my program on the circuit that I really wanted to measure, the phase shift went from-. 5 degrees up to about 1.2 degrees. The change in the values of phase shift at high frequencies (> 3000) was environ.2 degrees. Given the small phase shift, this variation is unacceptable. Now I tried to use a sequence to each blood individually (increase the maximum sampling frequency to 250 k) and then align the two signals and measure the phase of each shift. When I use align it and re - sample Express VI to realign the two signals, I get the message "error 20333 analysis: cannot align two waveforms with dt even if their samples are not clocked in phase." Is it possible to align two signals I describe here? I enclose the new VI as Phase 2

  Matthew,

  I think I have an idea for at least part of the problem.

  I took your program data and deleted stuff DAQ.  I have converted the Signal on the chart control and looked then what was going on with the signal analysis.

  The output of the Waveforms.vi line has two waveforms, like the entry.  However, arrays of Y in the two waveforms are empty!  It does not generate an error. After some head scratching, reading the help files and try things out, that's what I think is happening: the time t0 two input signals are 1,031 seconds apart. Since the wavefoms contains 1,000 seconds of data, there is no overlap and may not align them.

  I changed the t0 on two waveforms are the same, and it lines up.  The number of items in the tables is reduced by one. Then I increased the t0 of 0.1 seconds on the first element. The output had both greater than the entry by dt t0 t0 and the size of the arrays was 224998.  Reversing the t0 two elements shifts the phase in the opposite direction.

  What that tells me, is that you can not reliably align two waveforms which do not overlap.

  I suggest that you go to 2-channel data acquisition and that it accept the reduced sample rate.  You won't get the resolution you want, but you should be able to tell if something important happens.

  You may be able to improve the equivalent resolution by taking multiple steps with a slight phase shift. This is similar to the way that old oscilloscopes of sampling (analog) worked. Take a series of measures with the signal you are currently using.  The make enough average to minimize changes due to noise. Then pass the phase of the signal of excitement to an amount that is smaller than the resolution of phase of sampling rate and repeat the measurements.  Recall that I calculated that for a 5 kHz signal sampled at 125kHz, you get a sample every 14.4 degrees. If shift you the phase of 1 degree (to the point/mathematical simulation), you get a different set of samples for excitement.  They are always separated by 14.4 degrees.  Take another series of measures. Transfer phase another degree and repeat.  As long as your sampling clocks are stable enough so that frequency does not drift significantly (and it shouldn't with your equipment), you should be able to get near resolution of what you need.  The trade-off is that you need to perform more measurements and may need to keep track of the phase shifts between the various measures.

  Lynn

• phase shifted PWM with Ni 9401 and Crio

  Hello

  Do you have an idea of pwm shifted 180 degrees?

  (duty cycle frequency and variable difficulty)

  I tried a design, but it seems in the graphics design works on the realtime.vi but it does not work with the fpga.

  Graphic output pwm FPGA are distinguished by the real time as you can see in the pictures.

  On the other hand, VI Fpga produce two pwm, as seen in the oscilloscope when the fpga VI runs.

  However, there is no phase shift between the PWM waves.
  It is a part of my thesis, but I'm stuck in this problem, so I need assistance on your part.

  Thank you.

  Best regards;

  My hardware:

  cRIO-9024 and cRIO-9118 chassis

  NOR-9223, 9263 - nor, nor-9401, or-9474

  two nor-9225 and nor-9227

  Hi Maurice

  Thank you for your help.

  Yes I want to that they will be moved with the right variable and 10 kHz. I put 49% maximum duty.

  I put the output into the same output block.

  Square wave generator does not accept 'loop' while.

  I have attached a simple FPGA project file. Could you please tell me what is my fault?

  The resulting Pwm frequency is 10 kHz, the only problem is always the shifters.

  So, I always need assistance.

• How "block of surge protection" works in NOR-9225 and NOR-9227

  Hi all

  Hi, I use NI 9225 and NI 9227 to collect data under high voltage.

  According to the data sheet, the NI 9225 has protection against overvoltages and NI 9227 overcurrent protection.

  I wonder what kind of protections, they, I mean, if high voltage or current applied, what will happen to the material? Fuse has popped up? Or trip relay? Can I re - opening after the failure to tension?

  Thank you

  Jenny

  Hello Jenny,.

  We have an IC isolation that will protect some of the internal circuits. There is no fuse or relay you can replace. Because of this, if you exceed the specifications (±450 VDC for the RMS A 9225 and 5 / 10 A RMS for 1 s max with 19s cool time 5A RMS for the 9227), so will most likely damage your card. If you open the module, you will lose the warranty of your device.

• Phase Shift Key: Modulation Toolkit

  I am trying to simulate a phase shift key, I have followed an example of OR. the example worked fine and I used the same code but does not work my didi. The number of symbol is not correct.

  I have attached the VI, I could not know what the problem was. The chart of the constellation should remain constant, rather than moving and the number of symbol in the chart must be equal to the symbol on the control.

  Thanks for any help.

  Hello ade77

  Thanks for your post. It seems that your Eb/NO (10 dB) value is not high enough to get the right number of symbols in the right place. Try to increase this number and see if that helps. See the screenshot of your attached code.

  Let us know if this helps!

  See you soon!

  Corby_B

  http://www.NI.com/support

• Phase shift USRP N210 WBX has not remained constant

  Hello

  Here's the anouced;

  After setting the RF front end, each local oscillator can have a random phase offset by separators in the VCO/PLL channels. This shift will remain constant after initialization of the device and will remain constant until the device is closed or re-look.

  However,.

  I found the phase shift has not remained constant for some USRP N210 with WBX in system of synchronized receivers USRP N2x0 20 minutes.

  I'm currently building the measurement system of synchronized phase using USRP N200 x 2, x 2 OCTOCLOCK N210.

  CH1 and ch2 is connected with the MIMO cable

  Ch3 and ch4 is connected with the MIMO cable

  CH2 and ch4 is connected OCTCLOCK wiith 10 MHz and PPS.

  All entries were coupled to the SG not sincronized exit.

  attached screenshot shows the results observed for 200 minutes. .

  

  Right end indicates derivative of phase offset for 200 minutes;  white line is ch2 - ch1, red line is ch3 - ch1, green line is ch1 - ch4.

  It seems that each pair MIMO has kept the same phase offset but pairs diffreent MIMO.

  Is - this results?

  Here's the configulation in LabVIEW Block diagram.

  

  I tried like and found my phase USPR N210 WBX offset remains constant.

  http://forums.NI.com/T5/USRP-software-radio/USRP-time-and-phase-synchronization-for-source-localizat...

  My vi can be a bad thing.

  Sorry for the bad because of my misunderstanding infromation display.

  After fixing my mistakes of Vi, I'll show them.

• Two synchronized USRPs receive the same sine wave emitted by an another USRP, there is a phase shift random and obvious between the signals received from the 2 receivers

  Hello world!

  First of all, I use a USRP as a transmitter to emit a sine wave (the signal is exp(j2*pi*f*t)), and then I use the external clock to synchronize the two USRPs (Ref as PPS in are connected to the clock) as receivers. Receivers are in sync, and they are at the same distance from the transmitter, I thought that the signal they receive should have a nearly the same phase. However, in practice, the phase shift is big enough, and this problem really confuses me.

  It's the received signals of 2 receivers.

  Yes. What you observe is expected.

  Near the bottof of this document read the area 'alignment Phase vs Phase coherence '.

  http://www.NI.com/white-paper/14311/en/

  And also, for the alignment phase, see the following 'Angle of arrival detection with NI USRP '.

  https://decibel.NI.com/content/docs/doc-25716

  Erik

• cDAQ-9174 with modules 9225 and 9239 for issue of power measurements...

  Hello to one and all.

  I do turn a cDAQ-9174 with modules 9225 and 9239 to measure the voltage (120, 208-240, 277 VAC) and current (via the clamp amp i400, Fluke - 10mA/exit A) respectively.

  I have the set scale scale Differential No. (1:1 I guess) for 100: 1 for current and voltage.  With the acquisition mode set to "N samples", 10 samples to read, at the rate of 500 m.  This feeds into 'EPM_Power.vi' (polymorphic VI of the palette of EMP... can be downloaded here, http://sine.ni.com/nips/cds/view/p/lang/en/nid/209826)

  I try to check my numbers with an Analyzer of power quality of 435 Fluke and supporting that upward is a Fluke 179 True RMS DMM with clamp amp i200 (for current playback)

  Now, I'm running is my numbers I take data look like they're following a curve of fishing... the averages are on the right, but when my blood pressure is expected to be relatively stable, it's over the map... same story with my current readings.  I tried several different filters without success.  I would like to have relatively stable values for voltage and current so my other values are correct.  Is there a signal conditioner or filter that will help with this?

  As always, a point in the right direction would be greatly appreciated!

  Thank you!

  Chad

  Hi, Will,

  Your request for a screenshot actuall lead me to the solution.  Not enough samples!  I took little data too slowly and only seeing part of the wave of fishing AC each iteration.  .. that became glaring when I tried to this graph.  So I increased my sampling of 100 to 5 Hz and things seem to have settled things down a bit.  Thank you for the good question!

  SH?

  C

• Phase shift a channel and display

  Hello

  I'm working on a project for which I have to display the I-Q constellation plot and normalize the data to fit a circle of unit RADIUS.

  I'm able to do this, but the problem is sometimes the signal in one of the channels is very low and therefore, the plot moves close to the routes (Please find attached the file, this is the best position, if a channel has a weak signal, the movements from point to one of the axes). When this happens, I want to add a phase shift of the signal (45 degrees and multiples of it) to bring to the back for the best position. I tried to use the extracted tone vi phase go, add 45 degrees, but how to rebuild the spirit of the new signal phase?

  Can someone help me please?

  Thank you very much

  Despres

  
  

• How can I do a phase shift and amplitude change on wavefile which is read in

  Hello all

  I have a wavefile which has two channels, left and right, I would make a phase

  SHIFT and amplitude change on one of the channels.  Can I split each channel

  in the tables, but I don't know how to do a phase shift and amplitude change on the

  Table to get the new signal.

  TIA sal22

  Hi Sal,

  Here's a way to implement the phase change:

  

  In regards to the change of amplitude, you could just multiply all of the table with the desired value.

• variable phase shift between two analog output signals

  Hey! I would drive two different piezo elements with an sine - / square signals and have a phase shifted output signals. After some trail and error, I was able to get a second analog output on my card PCI-6221 (using LabView 8.2) also allowed me to have different amplitudes for both signals. However, I could not output signal having a frequency different and most importantly to my request to have one of the signals variably shifted phase.

  Thanks for the very useful suggestion. I have attached the file .vi installation I've run so far.

  Hello!

  A way to generate waveforms is using the analog waveform Toolbox. I created an example VI that is attached and that shows you a way to use the base generating function VI. I saved for LabVIEW 8.2.

  I hope this helps!

• Transformed Hilbert phase shift of 90 degrees

  I am usig transformed from Hilbert to provide me with a shift of the phase of the signal of a UHF radar unit.

  When I try to get the soft wave phase I get nothing. But when I replicate the output of the HIlbert and do a sinus I have the orginal without the phase shift wave.

  When I use a simulated sine wave and use the transformed Hilbert for her, I get a wave that is shifted by 90 degrees.

  So can you please help me with some splitters using Hilbert.

  There the best solutions for the phase shift?

  If you get a point at a time, use the version ptbypt as already mentioned. It includes a configurable size buffer.

• Meter with two adjustable phase shift

  Hello

  In this experimental device, I have a print head a TTL pulse-controlled piezoelectric ink jet delivering uniform droplets on a surface. I use the "time" version of the counter output vi (high-/ low-time) because it allows me to very easily change the characteristics of the droplets. I use a strobe approach for imaging the droplets as they are ejected. Basically, a strobe LED light is pulsed at a frequency that exactly matches that of the inkjet printhead. A CCD camera is used in order to imager droplets, who seem "frozen" on the screen due to the stroboscopic effect. Strobe LED is triggered by a train of pulses TTL (two pulse trains come from exits of meter on my USB-6353 X Series DAQ board).

  Of course, I could trigger both the inkjet Printhead and the strobe light with the same output of counter, which would ensure that their frequencies match. But it's really nice to have a 'strobe delay' that allows adjustment of the phase shift between the strobe triggers and printhead. The hardware supplied with the print head has this feature of strobe delay as an external button. It is useful, because you can basically lead through time by turning the button and view the formation of droplets when it leaves the end of the nozzle.

  I have a vi that may trigger sometimes the printhead and the flash, but I can't understand how to adjust a phase shift between the two, while the program is running. It should be possible, but I can't get it. I would really appreciate help with this. Attached is the draft code and a diagram which may help to explain what I want to do

  Thank you very much

  -Matt

  No - forget the INITIAL DELAY.  It's only for the (first) INITIAL pulse.

  You already want to adjust the time / low-time already, no?

  So having a new control called PHASE SHIFT, from scratch.

  Have a variable called OFFSET PHASE CURRENT, from scratch.

  When the PHASE SHIFT is modified (by the user), understand the difference between where he wants to be and where you are (control - PHASE CURRENT OFFSET) and add a lot of time the low TIMES, but only during a cycle.  Basically you're stretching of a cycle.  Store the new value in the course of PHASE SHIFT variable for next time.

• I've updated to 9.3 on my iPod and my Mini iPad; Night shift is now on the iPid but not the iPad Mini. any ideas?

  I've updated to 9.3 on my iPod and my Mini iPad; Night shift is present on the iPod, but not the iPad Mini. and ideas?  Thank you!  CB

  Night shift is only on the iPad Mini 2 and later versions. http://www.Apple.com/iOS/updates/

  -AJ

• Custom hardware and the module of ARM

  Hello world

  Our company is in the early stages of designing a custom measuring device. In the past we used Microchip microcontrollers (PIC16 and 18), a simple IDE and a C compiler, but for the new generation of devices we will use microcontrollers from Luminary Micro ARM. Since we are also users of LabVIEW, the choice for the LabVIEW embedded module for ARM seems logical. I read a lot of documentation OR and watched the tutorials, but I'm still uncertain on what we may or may not do with the module. Until we buy eval kits and the module, I need to have some facts.

  1. The 'heart' of our circuit is a microcontroller LM3S1968, this MCU is ARM Cortex-M3 based. It is listed in Keil device database (http://www.keil.com/dd/), then is also a LabVIEW "Tier 1" - peripheral (http://zone.ni.com/devzone/cda/tut/p/id/7066)? ".
  2. What I have to add the MCU manually to the project as described in http://zone.ni.com/devzone/cda/tut/p/id/7152, or can I just it select from a menu?
  3. We already have a LM3S1968 evaluation kit (http://www.luminarymicro.com/products/lm3s1968_evaluation_kits.html) and a programming JTAG device. We can use these hardware components to evaluate the LabVIEW ARM module or should I buy a complete kit of NOR (including the dev board)?
  4. Is a JTAG connector on our device and a connection for a JTAG debugger, all I need for debugging the device with LabVIEW?
  5. Assessment OR (http://sine.ni.com/nips/cds/view/p/lang/en/nid/205040) kit includes JTAG Keil ULink2 adapter on the photo?
  6. We want to connect the MCU to a converter A/D, the AD7738 of Analog Devices (http://www.analog.com/en/analog-to-digital-converters/ad-converters/ad7738/products/product.html). We will use the SPI bus for communication and I know what codes to send to get a basic reading. What I need to use the SPI-Subvi and send the hex codes or can I use a Subvi 'AD7738' built-in device drivers CD?

  I apologize in advance for the number of questions, it's just that the use of LabVIEW for the development of material is completely new to me

  Thanks in advance for your help.

  Paul

  Hello Paul!

  I'll try to answer your questions and I hope someone else can add more information if necessary.

  1. The 'heart' of our circuit is a microcontroller LM3S1968, this MCU is ARM Cortex-M3 based. It is listed in Keil device database (http://www.keil.com/dd/), then is also a LabVIEW "Tier 1" - peripheral (http://zone.ni.com/devzone/cda/tut/p/id/7066)? ".

  Answer: no, that would be a level 2 device, we now offer three level 1 devices and information on these can be found on the link you condition.

  1. What I have to add the MCU manually to the project as described in http://zone.ni.com/devzone/cda/tut/p/id/7152, or can I just it select from a menu?

  Answer: you need to add yourself as described in the link you provided.

  1. We already have a LM3S1968 evaluation kit (http://www.luminarymicro.com/products/lm3s1968_evaluation_kits.html) and a programming JTAG device. We can use these hardware components to evaluate the LabVIEW ARM module or should I buy a complete kit of NOR (including the dev board)?

  Answer: is trickier, LV Module Embedded for ARM in trial mode will have some limitations (size applications, can open the development environment for a number of days and so on), but it should not have limits when it comes to other targets as described in the links that you have already provided. When it comes to the JTAG interface, I would recommend using the Keil ULINK2 USB-JTAG.

  1. Is a JTAG connector on our device and a connection for a JTAG debugger, all I need for debugging the device with LabVIEW?

  Answer: I would like to make use of the Keil ULINK2 USB-JTAG Adapter for debugging and allows us to download the code on the target. In fact, it's the only way we can download code on the ARM, but we can use a serial port / TCP in addition to JTAG debugging.

  1. Assessment OR (http://sine.ni.com/nips/cds/view/p/lang/en/nid/205040) kit includes JTAG Keil ULink2 adapter on the photo?

  Answer: Yes.

  1. We want to connect the MCU to a converter A/D, the AD7738 of Analog Devices (http://www.analog.com/en/analog-to-digital-converters/ad-converters/ad7738/products/product.html). We will use the SPI bus for communication and I know what codes to send to get a basic reading. What I need to use the SPI-Subvi and send the hex codes or can I use a Subvi 'AD7738' built-in device drivers CD?

  Answer: I/O could be implemented using the basic IO layer provide us as described here:

  http://zone.NI.com/DevZone/CDA/tut/p/ID/7119

  http://zone.NI.com/DevZone/CDA/tut/p/ID/7144

  I hope this helps!