Impulses per kilometre high-speed conversion/measure

Similar Questions

• High speed continuous measurement of encoder with sampling frequency of 1 kHz

  I am able at all times the position of a linear encoder using a PCI-6602 counter card, and I need to know how to set up so that the counter rotating at high speed, but the data is inserted into the buffer at a frequency of 1 kHz.  I am able suddenly to a hydraulic cylinder, and I am not concerned about the event recording to high frequency except to the extent where they throw off the number considerably if the equipment does not run fast enough to detect all the impulses of the encoder.

  Now, I think is that the external sample clock signal control (routed internal pulse output counter) time rate whereby the equipment detects the impulses of the encoder and the rate at which it inserts data into the buffer.  With a pulse 100 per inch encoder and a sampling frequency of 1 kHz, the extended final position of the cylinder is turned off by +/-0.15 inches, which is unacceptable.

  I need calculate a speed of this information, so I prefer not to use software timed sampling to control this (it's more difficult programming for other reasons as well - several asynchronous measures).  Any ideas on how to configure the hardware to count faster than the speed at which she inserts counties in the buffer?

  OK, you're clearly on the right track here, so I will focus on some details.

  1. How do you know that the +/-0.15 "differences are * measurement error rather than * error of movement?  Why wouldn't be an accurate measure and a proposal which can vary slightly from the nominal value?

  2. I wonder some all electric noise and defects that may produce false edges.  The fact that the behavior was better by using a sampling rate limited (200 kHz) in the digital inputs may be that some of these flaws were so short that they were never captured.

  I did a ton of work with the Commission to 6602 encoder and I can certainly confirm that count equipment is sensitive to the edges in a few tens of MHz.  (I know its 80 MHz for edge counting, but I think I remember that it can be of the order of 20 to 40 MHz to accommodate the time of signal propagation extra of the quadrature decoding circuit).

  A small point of clarification.  You're talking about the speed at which the meter "works to.  The value of count is a register whose value is changed completely by the circuit, * independent * of the sampling frequency.  If you enjoy with material-clocked County in memory buffer or interrogation of software without buffer not a bit for circuits that increments / decrements the value of the counter register.  (In other words, I am completely convinced that you would get commensurate with position end even if you took only 1 sample software-polled after the end of the move instead of sampling at 1 kHz all the way through.)

  So, if the value of the counter is disabled, it is because the circuit detects producers of County of the edges that shouldn't be there.  Something you can try is to set up digital debounce filter for input lines of the PFI corresponding to the encoder Source inputs and to the.

  -Kevin P.

• A measure of speed high speed with encoder in quadrature and NI 9401 on cDaq

  Greetings,

  We use an encoder in quadrature with 360 pulses/turn on the tracks (track A and B) and no trace of Z to measure motor speed at startup. Data acquisition, we use a NI 9401 in 9178 cDaq chassis and a pc with LabVIEW. The problem is that the start-up period is relatively short (less than 1 second), during which we measure speed as precisely as possible. The speed range is from 0 to 10000 RPM.

  What type of measurement method that you would recommend.

  Here are a few methods that we have already tried:

  -Measure with DAQmx CIFreq--> high frequency with 2 counters: speed measurement, but with a very big mistake (+ 166 RPM).

  -CIFreq DAQmx--> wide range with 2 counters: good speed data but more slow measurement,

  -CICntEdges DAQmx (counting separated the two lanes, speed conversion): very incoherent speed data.

  Thanks in advance for your help.

  Matej

  I would definitely say a 4, the measure of a low freq called option with 1 meter.  (Frankly, I've never been

  fond of this name because it is useful for freqs much higher than what I expect most people think "low freq".)   This

  is the method that I almost * always * use for frequency of counter measures.  It works really well to capture transitional

  variations in speed.

  10000 rpm and 360 cycles/rev, you are looking at a maximum frequency of 60 kHz.  The frequency measurement mode 1 meter

  There will be 80 MHz internal clock by encoder cycle edges, then you will get more than 1000 strokes per measure.  The point

  that means only 1 number of quantization errors, you can expect<>

  Further, you can average overall, say, 10 samples to you give even better accuracy and you could still be a data capture

  rate significantly higher than the probable bandwidth of your mechanical system.  (The average would just clean the jitter and noise and would not

  Hide answer true mechanical characteristics).

  -Kevin P

• Urgent problem! Help, please. digitizer high-speed, too long channel switching time!

  Dear all experts of digitizer high-speed OR:

  I have a question about the two channel configuration using NI5154 digitizer (see need help to set up an acquisition of two channels using NI5154).

  As we need to make a measurement with NI5154 purchase very soon so a suggested by Efrain such DAQ card is not an option for our next experience. So, I'm trying to configure the NI5154 acquisition of two channels. I have set up the NI5154 to count impulses to both channels. Our experimental set-up will send impulses to channel 0 to 400 ms, then stop. 100 ms later pulses from another source will be sent on the channel 1 to 2 s.  I thought that the dead time of 100ms in our configuration would be long enough for the digitizer switch between channel 0 channel 1. But after some testing, I found that the digitizer takes longer to switch between channels.

  I did a test vi (NISCOPE - Timing.vi) just for the ms count how much it takes to the digitizer switch between channels. In the vi attached, if you run only one channel for a loop takes about 20 ms in my pc. If you run for the two channels, there are about 130 ms for a single loop. If you run a dual channel from the time of the loop is about 40 ms (I mean stop a channel and then re-run the channel).

  I don't understand why it takes so long to switch from channel 0 channel 1.  As I have tested the niScope Commit.vi consumes a lot of time for the second string. Is it possible to avoid this? We cannot extend the time-out for a long time of 100ms of series up so I have to get rid of this problem.

  
  

• high speed streaming

  LabVIEW 8.5

  Hi all. I have never written LV or any other code to make streaming broadband but I have to now. I did a lot of 2 and 3-way low speed data acq but never down. I could use a little guidance as to how it works.

  First of all - what I have to measure. I am able engine valve motion, in real time on a test apparatus part motor engine. I enjoy movement to a slow control RPM can accelerate to maximum speed while taking data. The scan will take 5 to 8 seconds.

  2nd - I need to watch. I need to look at the position of the valve for 1 round, taken in 720 points, at low speed and compare it to track even the test RPM. I have to select test RPM after the data are obtained and overlay lo & Hi plots, a control and a test track at the same time. All the analyses to be performed after data collection, not in real time. Sampling of the range starts at around 12 k samples/s and a ramp at 66 k samples/s up to 8 seconds, which will generate up to 312 000 points by scanning.

  3rd - I. High speed laser sensor position, more than adequate sampling rate. Rotary encoder, 720 cards data acq pulses/Rev. and chassis conditioner GIS with inputs / outputs. Boards are 6143-PCI and PXI - 6071e. 6143 Board is connected to the encoder and entered trigger. Output laser is 0 - 10v, so I have to use the jury 6071e for analog position signal.

  Now, my questions. I know that I can stream to get a high rate, but for analysis, I need to bite these data into pieces of 720 points and they relate to a registered PLAN. It can be analysed by discrete steps, say about 50 or 100 rpm. How to handle a stream from a writing Board and "stamp" with RPM taken of an encoder on a second table? I'm looking for some basic procedure here that will give the data for me in a way that I can actually use rather than a dump of 312 000 point that would take days to analyze without a few things. I calibrate the data after the fact and analyze in a separate program, so I just need voltage data flow. But I need to start at the pulse of Z and take a reading every pulse.

  Thoughts?

  I had LV 2012 running when I responded to your post above.

  I called LV 8.5 and put together this small VI.  It generates random numbers to approximately 66000 per second and runs for about 8 seconds.  It requires approximately 17 MB.  The screen requires a copy (I think) which roughly doubles the size of the data in memory.

  Reduce the wait to 1 ms and it runs in about 1 second.  It takes a zero waiting ms 76 ms.  Then save the data in a shift register or another form of memory will not be a bottleneck.

  Lynn

• Super High speed internet Time Warner installed (50mbps) but foxfire operating only at 1.35Mbps, while the internet Explorer works fine

  Internet (50mbps) Time Warner installed high-speed yesterday on my computer, but when the guy left I noticed that the speed was very slow. SIS one test on speedtest.net and found I was getting a maximum of 1.35mbps (sometimes as low as .62mbps). So I had them come back and they tried all kinds of things, only to discover Internet Explorer gets 50mbps, so it's something with Foxfire. What would it be?

  Hello, when you use speedtest.net or a similar site based on flash to measure your connection speed, it could be a problem with the protected mode that adobe has implemented for its flash plugin for firefox. Some older versions of f-secure or report of trusteer are known to cause slowdowns with flash, or it could be something similar on your system that interferes (maybe security software that block/sandbox the container used for protected mode, etc...).

  as a solution, you could try downgrading of 10.3 flash (which is always supported) or Disable protected mode & see if that makes a difference.

• data logger high speed

  Hello

  am very new to Labview. I used a data logger high-speed (labview 6i). Files are saved in the binary format. How can I convert files to ascii format or text for post-processing?

  Thank you

  Hi Valentine,.

  I hope you had a good weekend.

  I had a go at the conversion of the sample code down to LabVIEW 6, so you won't have problems to open it.

  It will be useful.

  Steve

• Capture high speed encoder data

  Hello

  I have a motion control project where I would record the position data. High speed capture is limited with sampling frequency of 2 kHz. But I have to save a lot more than higher speed.

  I read that there is another option that connects to the motion control card (I use a card PCI-7358) and the map of data acquisition using a RTSI cable and channels A and B of the routing of the data acquisition card encoder using the RTSI lines.

  I have 6143 and 6280, 7358 PCI DAQ cards and a RTSI cable.

  Q1. Which card is better to use? 6143 or 6280?

  Q2. When I look at the examples, I have seen that its possible to phase has the traffic and signals of the phase B of an encoder for the RTSI line with Signal Select.vi. But I couldn't find an example on how to read of DAQ card.

  Q3. How can I contact the encoder position phase has and band B pulses which is acquired from the DAQ cards?

  Concerning

  Hi serkanb,

  The 6143 has no support for measures of encoder quadrature (although you can run a task of count of edge and use the B signal as a line up/down to get a similar effect).  If you are interested, we'll find more information here (the 6143 uses the same SC I ASIC that make the E Series DAQ devices).

  It doesn't really matter too much since you have a 6280 that supports quadrature encoder measures (he uses the STC II ASIC).  To answer your direct questions:

  Q1.  The 6280 is better (see above)

  Q2.  You need to use a channel DAQmx property node to choose what terminals to use for your task of encoder:

  

  Q3.   I would like to start with an example of the expedition:

  Help > find examples... > input and output material > DAQmx > counter measures > Position > measurement Position.vi

  You insert the property node before starting the task (but after the channel is created).

  I hope this helps, if you have any questions do not hesitate to post back!

  Best regards

• Treatment of LabVIEW data and high speed data acquisition C

  Hi all

  I am designing a data acquition VI high speed of 3 cards acquition of data at the maximum speed. Data cards are PCI 2517 Measurement Computing. The sampling frequency for each card is 1 M samples/second, if the total sample of M 3/second of three cards. Problem is the LabVIEW drivers and the screws provided by the provider works very well just for a single card at maximum speed, but does not support multiple cards at maximum speed. Their technical engineer advised me to write code in c#, C++ or VB.NET for this data acquition high speed. If I use C forever, I would like to use LabVIEW for processing of the acquired data to data acquisition. I came across a few examples that suggest the creation of dll C code and then calling it a LabVIEW. But those who have programs simple and none of them speak in C data acquisition. My questions are,

  1. is it possible to call a C data acquisition program high speed of labview and not work in any kind of present of buffer overflow?

  2 would it not simple best to use labwindows CVI?

  3. is there another alternative solution that I'm missing?

  I'll appreciate all the entries.

  Thank you!

  Nilesh-

  It's pretty easy.  Arguments for CINrun must match wiring.  You can wire your CIN function block and say LabView to generate the C interface code to begin.

  Here's my pairs for the ASIO audio project.

  All the best,

  Terry

• T3i sync high speed with popup flash?

  When shooting outdoors with a light background, it would be nice to be able to use the flash pop-up as a fill light (to the shadows on a face, etc..). However, the shutter speed is set to 1/200 when the popup flash is in place, overexpose the scene. Is there a reason why the pop-up flash can't sync high speed like an external flash to allow a faster shutter speed and always get a filling?

  Thank you

  David

  It has to do with the amount of energy is available for the flash.  A more powerful flash can more easily manage the sync high speed.

  Sync and sync high speed are related to the work the Shutter curtain on any SLR digital.  There are two doors.  A slides open, and close other slides.  The reason for which there must be two doors (instead of one) is because that if there is only one, then the door would slide open, then reverses to slide.

  Assume the following scenario were true:

  Suppose it takes the shutter a full 1 second door to slide open.  If we set an exposure time of 2 seconds, the following should happen if there was only one door.

  -l' shutter starts to slide open from left to right, allowing light to reach the pixels on the left edge of the sensor.  The right edge is always in the dark.

  -as slides of doors, more and more pixels are eposed to light.

  -a second later reached the opposite end and all the pixels are exposed to light, but the door must immediately reverse and start close because it will take a full second to slide the door closed.

  -the door begins to move and immediately the pixels on the edge of most on the right are in the dark, because they are covered by the shutter, but the pixels on the left edge are still exposed to the light.

  -the door has finally reached the edge against a second later and no pixel is exposed to light.

  Think to what just happened... the pixels on the edge of 'left' of the sensor got a second exhibition 2... but the pixels on the right edge of the probe were barely exposed for a fraction of a second.  You'd have a horrible blow to look.

  To resolve this problem, the camera uses TWO doors... begins a sliding open... the other follows a moment later (based on the selected shutter speed) and starts sliding closed.  Now, all pixels are exposed for the same period of time, regardless of the shutter speed you use.

  But the reality is they are mechanically sliding doors and it takes time to move.  Flash sync speed is shortest possible exposure that can be turned where the first door has enough time to COMPLETELY slide open so that when the flash goes off, the entire sensor is exposed and benefit of lightning.  The second door can slide THEN closed.

  If you do not use flash and you set a very fast shutter speed (say 1/1000th) the second door actually starts closeing long before the end of the first door opening.  In fact the second door is "hunting" the first establishes a "slot" which sweeps the sensor.

  With this in mind... now think just what a flash how to predict sync high speed.

  Assume that your camera has a maximum speed of flash-sync of 1/200th, but you want to shoot at 1/400th.

  This means that the first door must begin to open.  When he reached the midpoint, the flash must trigger to light the subject - but half the sensor did not lightning.  The second door closes as the first door continues to open up.  When the first door reaches the opposite edge, the second door will now be in the middle.  The flash needs to fire AGAIN - this time to expose the pixels on the 2nd half of the sensor.

  This means that the flash should fire TWICE in quick succession and the impulses must be PRECISELY 1/800th second (half or your second 1/400th total exposure times) apartment.    No flash would be able to recycle in just 1/800th dry if she gave a burst of the power of the light.  In other words, that it must reserve at least half of its power for the second round.

  If you increase the shutter speed to 1/800th... now the flash to trigger FOUR times and no single burst may be stronger than 25% of the power of lightning - and gusts must precisely timed occurs 1/1600e seconds, independently of the other.

  You can quickly see how this is going to require a flash with a power or you won't be able to finish the sync high speed on something more than just a few feet.

  For the light of day, the most brilliant exhibition is going to be the sunny 16 rule... f/16 with the shutter speed, the value in contrast to ISO.  So, for 100 ISO, you can use 1/100th sec.  To f/8, you can use 1/200th (and now you are still below the max flash sync speed).

• Internet high speed only is not what it should be

  I have ThinkPad R60e, with Broadcom NetXtreme Gigabit Ethernet adapter. I guess I've always had a problem with internet high speed, but I did my best to ignore it until now. Any plan the supplier announced, I've always had a tenth only speed, download and send. I used to blame it on them, but now I changed the provider and the problem persists. So I researched what other users with the same plan, and they become quite at announced rates. So I guess there must be something wrong with the settings. Advertising plan up to 2 Mbps download and 200 kbps upload. What I get on practice is maximum of 200 kbps download and on average 20 Kbps upwards. Help, please! It is most annoying.

  I forgot to add, I use Windows XP, the problem for most with Ethernet connection since I use it the most. But wireless seems to act in a similar way.

  How will you measure your network speed.  Any chance that your bandwidth meter reports bytes/sec instead of bps?

  Sorry, I had to ask (Zoltan ducks for cover...)

  Z.

• I made a video on the iPhone 5 is and it reads at high speed?

  I made a video on the iPhone 5 is and it reads at high speed?

  have you done a video time?

• Internet high speed &amp; 1stgen AirportExpress

  Recently I upgraded my internet speed to 150Mbps. using my (model A1264) 1stGen Airport Express, I am only able to get 50Mbps to my office. My iMac is at short range with my router. My internet is slow speed b/c my Express is outdated? A new Express will allow me received the speeds I have upgraded to or is a desperate need? On the 2nd floor, there is an another desktop or home that connects to the internet regularly (teenage son online games).

  The 1 st Gen AirPort Express and 2nd Gen AirPort Express have only 100 Mbit/s Ethernet ports, so in theory, it would be the top speed that the Express could never offer.

  To the extent where wireless is concerned, 50 - 60 Mbps would be what to expect from an AirPort Express which is provided a 100 Mbps connection, since he has never been known for its performance wireless... primarily because of a small simple antennas buried in the product.

  A new AirPort Extreme has 1 000 Mbps Ethernet ports and the much higher speed wireless capability... (six wireless antennas all located towards the top at the top of the "tower")... which would be the product to try if you want to stay with a router from Apple.  At Apple, and you buy a 14 day no questions asked return guarantees, so if the product does not wait, it may be returned for credit or refund.

• WiFi unstable and slow Internet high speed

  Hello world:

  Recently, I am facing a problem of unstable wifi, slow speed of the internet of my macbook pro. I hope someone could help me with my problem.

  
  

  Symptom:

  Internet mainly speed just unstable using a wifi connection. (no problem with wifi connection self and my wifi suddenly grave would not be)

  Example:

  • FaceTime with my friends and the connection would suddenly abandon or images & audio gets fuzzy.
  • Videos in online streaming and suddenly occurs buffering.
  • Download file of software update iPhone via iTunes, the speed is slow, he needed to take 2 h at the end and later on a window display "cannot download and check your internet connection".
  • Suddenly cannot open websites like site apple.com, google.com. Sometimes it will take more time to open Web sites.

  Hardware and software:

  MacBook Pro mid-2009, OS X EL Capitan 10.11.5

  ISP: Cox, 50Mbps

  Modem & router: Netgear N450

  Test:

  Turn off my wifi and connect my macbook pro with modem & router with cable, internet high speed is stable and fast. Internet speed download speed test result display is of around 60Mbps, download speed is around 8Mbps. And I tried streaming using the connection cable, there was no buffering.

  I already tried the possible Solutions:

  • Restart the Macbook pro and restart Modem & router: will not work. I mean the internet will be very well at first, but later would be unstable again.
  • Reset Wireless Modem & router and change channels: useful, but not completely solve the problem. After you change the wireless channel, I tested my internet speed and the result showing 20-40Mbps (slower than 60mbps) speed download. Sometimes, the result will be like 6-8Mbps and sometimes it will be 60Mbps. If its unstable.
  • Wireless diagnosis: result indicates connection is good.
  • Called my ISP provider: they checked and said all right.

  
  

  Other Questions & details:

  • The internet is ok for most of the time. But when all of a sudden I can't open site or I can't download and streaming & FaceTime at normal speed, his frustration.
  • I thought it might be related to my hardware since its an old macbook pro. I can't run Apple hardware test because I don't have the installation disc more and my macbook pro is very old. Is it a third party software that can perform the test hardware on mac?
  • My wifi used to be very stable and I don't have to worry. Just for these last two weeks.

  
  

  
  

  I really appreciate your time and help! Looking forward to any reply!

  Wi - FI connection drops

  Connection Wi - Fi in OS X Yosemite problems

  Wi - Fi in OS X Yosemite connection problems (2)

  Connection Wi - Fi in OS X Yosemite problems (3)

  WiFi potential temporary fix - Yosemite

  Also try turning off Bluetooth.

  WIFI AND BLUETOOTH FINALLY SOLVED, NOT REALLY - YOSEMITE 10.10

  If your Wi - Fi source is capable of generating a 5 GHz Wi - Fi network, try that in order to avoid conflicts with Bluetooth.

• Support very high-speed Modem

  I'm doing now with my high Modem or a high speed modem (DOCIS 3.0) can Firefox (Version 10.0) handle this?
  I'll run to about 5mbs/s - Upload and Download of 20mbs/s about.
  Thanking you in advance.
  JOE
  [email protected]

  You may need to wait for a response for more than three minutes, it's not instant messaging or chat.

  Yes, Firefox should work correctly with this type of broadband services.