FP-CTR-500 don't read external count inputs

I have 4 frequency signal inputs (0-10 KHz) connected to ports 2,3,4,5 of one FP-CTR-500, but I can't read any change on counting values, using FieldPoint Explorer. The module is OK, all the LEDs are green, including those four inputs, the firmware version of FP-1600 is 4.11 and software version of FieldPoint Explorer is 3.0.0 I can view a fix value of 53xx counts on each input, after a power up sequence (the external frequency is 8.2 KHz aprox.). What can I do?

There are several reasons that you may be having problems with the count. First, if the channel LED is always on, then the signal wired into the FP-CTR-500 may not be going low enough (below 6 volts) for the module to see the falling and rising edges. Second, if the inputs have been configured with the 200 Hz low pass filter setting, you may be filtering out your signal. Third, if you have configured the count channels for internal count inputs (1 kHz Reference or 32 kHz Reference) or previous count channel, then the module is not looking at your actual wired signals. Fourth, If you have enabled the Gate Inputs (channels 8-11) for any of the counters, then the count will not increment while the gate is low. Fifth, if the channel is configured for Reset On Read fu
nctionality, every time the FP-1600 polls the FP-CTR-500, the channel will reset itself.
Regards,
Aaron

Similar Messages

Counter Output/Counter Input PXI Signals Behaving Erratically

Question for all your LabVIEW guru's out there,
I am running a frequency loopback test using the NI PXI 6229 MIO DAQ card. I am generating a "Counter Output" pulse train signal which feeds through my device under test and then back out of my device under test and back into the PXI 6229 for a "Counter Input" frequency measurement. Both the "Counter Output" and the "Counter Input" are assigned different PFI lines using DAQmx in LabVIEW.
I have 4 lines to test on my DUT. All four lines run this same frequency measurement but with different PFI lines on the PXI 6229. Each line is test independently.
This is my setup for the 4 lines:
Path 1: P2.0 (Counter Output - Pulse Train) -> DUT (Device Under Test) -> P2.1 (Counter Input - Frequency Measurement)
Path 2: P2.2 (Counter Output - Pulse Train) -> DUT (Device Under Test) -> P2.3 (Counter Input - Frequency Measurement)
Path 3: P2.4 (Counter Output - Pulse Train) -> DUT (Device Under Test) -> P2.5 (Counter Input - Frequency Measurement)
Path 4: P2.6 (Counter Output - Pulse Train) -> DUT (Device Under Test) -> P2.7 (Counter Input - Frequency Measurement)
where:
P2.0 = PFI8
P2.1 = PFI9
P2.2 = PFI10
P2.3 = PFI11
P2.4 = PFI12
P2.5 = PFI13
P2.6 = PFI14
P2.7 = PFI15
I have a LabVIEW VI which generates the "Counter Output" and reads the "Counter Input" frequency. I am seeing weird behavior from the PXI 6229 card. I can test "Path 1" and "Path 2" and the frequency I read is what I generated. No issue there. However, when I test "Path 3" and "Path 4" the frequency measurement is erratic. The readings are two different frequencies repeated over and over again and none of those frequencies are the expected frequency which was generated out of the "Counter Output." If I reset the card, and start by testing "Path 3" and "Path 4" the frequency readings are correct and the erratic behavior is gone. However, when I try to then test "Path 2" and "Path 1" now those lines have the erratic frequency issue. I can continue resetting the card and see same issue. The PFI lines that I test first will always pass.
To summarize:
Steps Taken:
1. Test Path 1 = SUCCESS
2. Test Path 2 = SUCCESS
3. Test Path 3 = Erratic Frequency (Two Frequencies repeated over and over again in my frequency results array)
4. Test Path 4 = Erratic Frequency (Two Frequencies repeated over and over again in my frequency results array)
5. Reset the PXI 6229 Card
6. Test Path 3 = SUCCESS
7. Test Path 4 = SUCCESS
8. Test Path 3 = Erratic Frequency (Two Frequencies repeated over and over again in my frequency results array)
9. Test Path 4 = Erratic Frequency (Two Frequencies repeated over and over again in my frequency results array)
I am wondering if Port 2 (P2.0-P2.7) on the 6229 card has certain dependecies and this is why I am seeing issues. I am trying to get around this issue so that I don't have to always reset the card.
Are P2.0-P2.3 (PFI8-PFI11) and P2.4-P2.7 (PFI12-PFI15) treated differently or require different setup? How do I resolve this issue?
Thanks so much!

I have a theory...
The DAQ card follows a policy called "lazy uncommit" wherein the terminal used for the output will continue to be connected to the counter even after the task has completed (until the terminal is needed for something else). So as you run more tests, the counter output will end up driving more lines. This behavior should be easy enough to confirm.
As the DAQ card drives more lines, I'd imagine this affects the actual signal. You could scope it to check, but it sounds like either the rise/fall times are becoming longer or some extra noise is being introduced on the line.
The readings are two different frequencies repeated over and over again and none of those frequencies are the expected frequency which was generated out of the "Counter Output."
This implies you are picking up an extra edge during transitions--this isn't too uncommon if the signal is noisy since there is no built-in hysteresis on the DAQ card. I would expect the measured frequencies to have periods that sum to either the full period or the semi-period of your actual signal (depending on how many duplicate edges are detected).
Suggestions are as follows:
To stop the DAQ card from driving multiple PFI lines, it would probably be easiest to just programmatically reset the device in between your tests (using DAQmx Reset Device). If you can't reset the device (e.g. because you are running some other task that can't be interrupted) then you can instead configure a dummy task that uses the PFI line in question as an input.
To stop the DAQ card from picking up multiple edges during transitions, you should configure a digital filter on the input terminals. If you reset the device it sounds like this might not be necessary... it's up to you if you want to configure this or not.
Best Regards,
John Passiak

We are reading 4 external counting signal and 1 internal 32 Khz clock simultaneously, via a FP-CTR-500 and a VisualBasic app

lication with OPC server. Can we assure that the time of reading of values for all the channels is the same?. We need to compare those 4 external counting values between them, using the 32 Khz internal clock like a time base reference. Can anybody help us?The timing of reading from the VisualBasic application is 2 seconds, and external pulses are incoming at 8 Khz aprox.

lication with OPC server. Can we assure that the time of reading of values for all the channels is the same?. We need to compare those 4 external counting values between them, using the 32 Khz internal clock like a time base reference. Can anybody help us?Eduardo,
The FP-1600 should be sending data is relatively synchronized to the OPC Server. However, since items containing multiple analog/count channels are not allowed in the OPC Server, the OPC Server is treating the channels as separate channels and may not be transmitting the data simultaneously.
The more complete picture looks like this: The FP-1600 reads all 6 channels of the FP-CTR-500, it compares each value to the configured deadband and places any values that have changed in the transmit queue, it then does the same thing for any other I/O modules on the system. Following the scan of the entire bank, it transmits all of the changed data to the client computer. It then starts scanning the bank and the process repeats. The OPC Serv
er on the client computer breaks the data down by channels into the appropriate memory locations. An OPC Client will establish separate requests for each channel. Thus a client may sequentially request data from separate channels and may get data from different times if the OPC Client has updated channels between responding to one data request and then the next.
Regards,
Aaron

Problem resetting count on read with fp ctr-500 counter

Using the ctr-500 module with a FP-1000. I want to reset the count of a channel on each read. The CTR-500 manual says to selecting "Reset on Read" from the Value menu. I've done that but the counter never resets when I read it. I then tried clicking on "Creat item" under channel attributes in MAX. It creates an item called "Read Reset Mode @Count Input 0" under Data Neighborhood. Added that item to the program and wrote to it with both a 1 and 0, but when I read channel 0 it still will not reset. Obviously, I'm missing something. I would appreciate any help or a simple example so I can get this resolved. Thanks, Mike
Message Edited by mike72903 on 01-31-2008 10:51 AM
Attachments:
reset count1.vi ‏15 KB

Found an example. Thanks anyway

Pulse Counting Problem CTR-500

I am using a couple CTR-500 on a compact fieldpoint setup to measure pulses from 2 energy (BTU) meters, 3 diaphragm gas meters, 2 liquid flow meters and 2 Watt-hour electrical meters. I seem to have a problem with my pulse counts accelerating upon start up of the program (up to 1000 pulses/15 minutes <- which is unrealistic for the hardware installed and then falling to 5-10 pulses/15minutes <-reasonable value). The pulse count does not correlate with the manual meter readings I have taken either, with the exception of the Watthour meters. I am unsure if it is my program, wiring, or peripheral equipment at this point.
Has anyone seen a problem like this before? I have included a couple graphs showing the raw pulse count (saved every 15 minutes) and the change in pulse count every 15 minutes.
Solved!
Go to Solution.
Attachments:
Pulse Counting Run Away.pdf ‏128 KB

Here is an example vi of how I am reading the pulses and some data processing I am doing with the signal. I have built in a totalised pulse counter to compensate for the maximum of 65535 pulses that can be counted by the module - so I do not miss pulse counts on reset.
Attachments:
Example code for counting.pdf ‏60 KB

CTR-500 module reading too many pulses?

Hi. I am using a CTR-500 module as a totalizer to count the pulses coming from a turbine flow meter. The flow meter is calibrated for 1 pulse/L and our pump is displacing 5-10 L/min. The pulse's high state is about 18VDC.
The problem we are having is that when the pulse occurs, the pulse count goes up by 5-40 counts (sometimes more). The LED on the module behaves properly and matches the pulse output from the flow meter but the reading we get in NI-MAX is not right. I'm sure this is something simple that I am missing but I can't seem to get it to work right.
I have the feeling that the module is reading many false highs as the pulse is high for a good second or so. How to I get the module to count only the rising edge of the pulse and ignore the rest?
Any help is appreciated.
Thanks,
Dave

Hi Dave,
CTR-500 does use edge counting. You can perform a software check to see if it is still at a high and if it is then not do a count and if it is not the increase the count. The green ready light just indicated that the module is working in normal mode and the green status indicator light turns on when the channel is used. Have you tried using a different flow meter with this?
Warm regards,
Karunya R
National Instruments
Applications Engineer

Why does Lookout receive wrong count from FP-CTR-500

Counter module flashes light count = to field pulse input device. Lookout fieldpoint object follows device count, but occassionally double counts giving wrong results. Is this a hardware problem with the counter module? A second counter in the system works as expected. Both are wired the same way and read the same way in the software and are receiving signals from like field devices.

Mike,
To rule out the possibility of this being a hardware problem in the FP-CTR-500 module, you can swap both of your FP-CTR-500 modules. I suspect that the problem will remain on the same signal/channel indicating that it is most likely a signal problem.
You may be receiving a double count as a result of noise or signal differences in the sensors wired to the various channels. To reduce the likelihood of a spurious signal causing a double count, you can enable the low pass filter on the FP-CTR-500 to reject signals above 200 Hz. If you look at the signal on a scope, you may see that it is fairly noisy and could use some filtering. Also, consider if one sensor has a longer cable run then the other or if it routes near something that may be electricall
y noisy.
Regards,
Aaron

How can we substitute the invalid option "reset after read" in FP-CTR-500 + FP-1600 frequency measurement application?

We nned to incorpore the values of 2 frequency signals (0-10 Khz)into a process controlled by a VisualBasic application running on 1 PC with W'95. Because the FP-CTR-500 working with FP-1600 hasn't the option "reset after read", the process of reading is a bit complicate, and sometimes, we receive wrong values of frequency from those devices. Could you help me? Is there any extremely reliable method of reading? Best regards,
Puho

For frequency measurement information on the FP-CTR-500/502 modules. Please see KnowledgeBase Article #1TB63SUS
http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/d8db42f9fdc3607e862568640047f144?OpenDocument
Ultimately, the FP-CTR-500/502 modules are not designed for frequency measurement, although it is possible to use them to measure frequency. The one thing is that it works best to do the measurements over relatively long integration periods (1/4 second or more).
Regards,
Aaron

CTR-500 field-device power

Hello forum,
I have recently started my FP adventure, and am pretty impressed with what I have achieved so far ... Still, since I completely lack knowledge of electronics, I hesitate for the following. I have an FP-CTR-500 that is neatly counting pulses from anemometers, water-consumption counters etc. All these devices are powered through the 24VDC power that I piggy-backed from the FP1600. Now, the new counter I'd like to install takes 3VDC in the pulse-generating loop, and I wonder whether I can have this connected to the same CTR, and in what way. Can I use a separate external power supply ?! Any suggestions ?! Thanks a lot for your help,
Amicalement,
Jan Bayer

According to the
device specifications the CTR500 input range is 10 to 30 VDC, so your
understanding is correct on that point. Hence 2 solutions : either you manage
to use signal conditioning to increase your input voltage, or you have to use
another device.
Regards,
Matthieu B.
NI France
Cordialement / Regards, Matthieu B. @ NI France.

How can I measure RPM with CTR-500 module?

I have used the CTR-500 module for mesurement of motor RPM. But it doesn't have direct option to measure RPM ,
so i have count pulses for 1sec (then reset the counter) and by calculation show the result for 1min. But it varies every time ,cant give me fix RPM.
I want reliable solution for this.

min
You have not said how much the RPM actually varies from reading to reading and what the range of measured RPM is for the process. This variation can be caused by a couple of things. One would be actual variations in RPM due to changes in motor loading. What is this motor driving? Most RPM readouts use some form of sample averaging to smooth out the readings.
A second cause could be your vi. Suggest you post a copy of your vi.
In case you have not seen it, here is a link to a KB about measuring frequency with cFP. It also links to several other docs on the same subject . http://digital.ni.com/public.nsf/allkb/D8DB42F9FDC3607E862568640047F144?OpenDocument

FP-CTR-500 and Frequency Measurement: How to modify it to report the frequency (0-10 Hz) every one minute?

How to modify "Frequency Measurement" to report the frequency every one minute?
The signal frequencies vary from 0 to 10 Hz (see the analog output plot and attached sample data file), so I want record the average frequency every one minute.
Software: Labview 8.5
Hardware: FP-CTR-500
Program: "Frequency Measurement" --build in and under "NI example finder", It was attached with this message.
Physical wiring: (1) The signal I want to measure to count input 1 (pins 2 and 18). it is a pulse signal (range from 0 to 1 V, see the plot and attached data file).
(2) Wire Output 0 (pin 130 to gate 0 (pin 9). Do com pins 26 and 30 need to wire together?
FP-CTR-5000 was set up in Max based on the program instructions. I have tried different gating pulse frequency, my readings are always "0".
Attachments:
H2O_20130809.xlsx ‏18 KB
Frequency Measurement.vi ‏35 KB

CTR-500 high pulse is >=10V. Hence, it always read your pulse as low. With this low voltage pulse, you must use analog input module, and write a program to read pulse from analog level. You must also make sure that you pulse is not so narrow that cFP loop is not fast enough to capture voltage change.

Vbnet counter input channel read

VB2005 Counter Input DAQmx Single Reading
I have been tasked with upgrading a previous vb6 application using DAQ Legacy
to .net using pre-existing components.
6052E and 6601. I am a vb.net programmer, not an engineer,
nor did I write the original application.
- lots of deciphering and figuring out terms that I am very
unfamiliar with.
6052e = Dev1
6601 = Dev2
Encodertype = x4
zIndexEnable = false
EncoderPhase = AHighBHigh
PulsesPerRev = 60
SampleClockSource = “/Dev2/PFI39”
Rate = 1000
Samples = 25
Taken pretty much straight from the example -
myTask.CIChannels.CreateAngularEncoderChannel(counterComboBox.Text,
encoderType, zIndexEnable, zIndexValue, encoderPhase, pulsePerRev, _
0.0, CIAngularEncoderUnits.Ticks)
myTask.Timing.ConfigureSampleClock(sampleClkSourceTextBox.Text, _
Convert.ToDouble(rateTextBox.Text), SampleClockActiveEdge.Rising, _
SampleQuantityMode.ContinuousSamples, 25)
I have installed DAQmx 8.5 and have been reading the help
and scanning the samples to try and figure these things out.
Specifically MeasAngularPositionBufferedCont_ExtClk, after calling
and getting help, I was finally able to get this sample to work.
In my application, I have my own counter object that I
instantiate and each of the four has its own task, CIChannel and reader. When a
channel is selected, the task is configured, the channel added, the task timing
configured and the task started, when the object is unselected, I dispose of
the task and channel. In my gui I have a timer event and if that channel has
been selected, then I call its getcurrentvalue method, which calls the reader
to get value asynchronously and pumps it to a textbox. This same type of scheme
worked for me with the AIChannels, but trying to get counter angular position,
all I am able to get is error -200284 pretty consistently.
I have matched all my criteria to the working sample, but am
unable to get a value returned. Better yet, after I start my app, even if I don’t
enable one of my channel objects, I can no longer run the sample application.
I have found that after I run my application I can use the
original application (which is using the DAQ Legacy) and initiate a read and
then close the original application and everything is reset aka I can
successfully run the sample application again.
QUESTIONS:
Is there a way to test the start trigger to determine that it
is configured correctly?
I have the task set up for external timing and the clock
works on the sample how can I verify this is working in code?
Any idea of why I would have to go into the original
application in order to get the sample to work again?
Any know of other vb code examples that might relate that
you could point me to?
Thanks for any help
CMWell, time to get back to the frustration...

Hi,
Is there a way to test the start trigger to determine that it is configured correctly? - Where are you using a start trigger? - I didn't see a mention of it in your description. When troubleshooting triggers I ussually end up checking 3 things. First, I confirm that my physical trigger source is outputting a TTL signal. Second, in Max I do count events on the PFI line I have the signal connected to in order to confirm my connections. Third, I try a simple example - if it will trigger in the example, then it will trigger in my code as long as the call is made with the same settings and configurations.
I have the task set up for external timing and the clock works on the sample how can I verify this is working in code? I would start with the first two steps from above. In your case, PFI39 is an actual enoder signal if I recall correctly. With the error that you receive, -200284, one of the causes of that is when there is not external clock signal (do a quick search on ni.com for "200284" and check out the first link) - is your encoder moving when you take these readings? If there is no clock signal present, then the task will not latch in values. One good way to work around this is to use another one of your counters to generate a pulse train and use that output as a clock signal instead of PFI 39. Also, if you just want to grab single values, you don't have to do a buffered acquisition - you can figure timing for "on demand" and not have to woory about clocked values. Either method should work.
Any idea of why I would have to go into the original application in order to get the sample to work again? That ones a little tougher. If somehow you are leaving the task in an undefined state (not stopping and clearing) it can cause some issues with the next iteration. You may want to try reseting the device at the beginning of your program.
Any know of other vb code examples that might relate that you could point me to? I think you're already looking at a good shipping example, you may want to try modifying that before trying different setups in your application.
Hope this helps, please don't hesitate to post back to this thread with additional questions,
Andrew S
National Instruments
Getting Started with NI-DAQmx
Measurement Fundamentals

Frequency in cFP CTR 500

Hi, I got a VI to read frequency from cFP 2020 with the CTR-500 module (Frequency Measurement.vi) in NI Example Finder. When I run this VI in LabVIEW for Windows, it's all right. But I want to run it embedded selecting the target and, when I do it, I cannot read the frequency. Does anybody knows what could be happening? Thanks

Hi letreca,
I took a look at your code and it doesn't look like
anything is really wrong there. There was one thing that I think might
help you. Because you do not have any sort of data dependencies, you
could be causing a condition where you are resetting the counter before you
read it. The best way to change this would be to connect the error out of
the Read.vi with the error in of the Write.vi.
You mentioned in your first post that you were using
Frequency Measurement.vi from the example finder (Browse > Hardware Input
and Output > FieldPoint > Advanced); however, the code for frequencia.vi
looks completely different. If you run the example do you get the same
behavior?
I think you may be having an issue mentioned in the first
paragraph because you may be resetting the counters too early. Try the
example and if that works, use the same technique. If that doesn't work,
then try to modify your existing code as described. If neither works tell
me what has changed and what hasn't so I can try to take a closer look into
everything.
Regards,
Otis
Training and Certification
Product Support Engineer
National Instruments

Looking to purchase a 500 GB-1 TB External Firewire HD. Suggestions?

I mainly use my 17-inch Powerbook G4 for Film/Video production (Final Cut Studio, Final Draft), and, as such, am just about out of hard drive space. I have about 55 GB left, which to some might seem like a lot, but since I'm using it now as my main scratch disk (place for storing video files), I don't expect it to last me two months, if that. So, I'm looking for a 500 GB- 1 TB external HD, preferably Firewire (Sub-question: is Firewire the best choice?), and was wondering if anyone had any experience with external drives on par with what I'm looking for, and if anyone could recommend any drives. Thanks a bunch.
17-inch Powerbook G4 Mac OS X (10.4.5)

55gb in a Final Cut Studio environment isn't much!
If your going to use the external drive purely for external storage so you can continue to use your PB internal hard drive as the main drive, then speed (USB vs FW400 vs FW800) is not as critical as it would be if you want to use it for your realtime scratch space, for example. However, that said, I'd still recommend you get FW800. Anymore, most external enclosures that support FW also support USB. And a FW drive can be booted off of, where USB-only can't.
Recommend an external unit that has it's own power supply. Some devices want to use power off the USB or FW, and sometimes there are power issues, usually with USB. Having it's own power supply negates any potential problem there.
Then you should decide if you are going to buy a complete drive that you plug in, or assemble your own. Some considerations, and one path if you want to build your own:
Most external hard drives have one year warranties. You can get a drive with a 3-5 year warranty if you assemble your own. It's not difficult to assemble your own...may sound scary, but it's pretty straight forward.
Assemble your own, requires the hard drive and case: There are a number of 3.5" 500gb hard drives available with 3-5 year warranties (I like http://www.newegg.com , for prices and good service). Although lower capacity, 320gb drives are quite a bit less expensive than the 500gb drives. In the 320's, I prefer Western Digital drives as they tend to run cooler than Seagates.
Add a Rosewill RX30 external case (includes power supply and USB/FW 400) $60. This brushed aluminum case looks like it was made to sit right next to our PB's (I've got one). You can see it at their web site at http://www.rosewill.com/product/product.aspx?productId=80 or also at Newegg. If you want, the Rosewill case also comes with FW800 for another $35.
Assembling it is very easy - you can read the directions on Rosewill's site at http://www.rosewill.com/RosewillSoftware/RX30_eng.pdf , for example. You disassemble the case by taking out 4 screws on the bottom of the Rosewill case, plug the included plug into the hard drive, secure the hard drive with 4 screws to the case, and reassemble it.
I use the program SuperDuper to back up my PB files to the external drive, and would recommend it. There are other backup programs, too. SuperDuper can be found at http://www.shirt-pocket.com/SuperDuper/SuperDuperDescription.html

Voltage loss on incoming signal to CTR-500

I have an optical sensor with at 12Vdc power supply hooked up to a CTR-500 module with the cFP-2020. I am trying to set it up to pick up the RPM of a motor. The speed range of the sensor is 1-250000RPM which is more than enough since the max I will see is 4000RPM. With the Power supply either routed through the Module or not through the module, I can see a 10V pulse on a scope comming from the sensor(when sensor line is not connected to module) But once the signal is connected to the channel I want to read it with, the signal Pulse Voltage drops to about 8.5Vdc, which is under the requirement to generate a count.
Can anyone tell me why I am getting a voltage drop? How can i fix it.

rameymm,
The 10 V you read from the sensor with a scope, what is the ground referenced to? When you are measuring the voltage at the inputs of the module, COM is tied to the ground of the 12 V power supply. It is possible that you have a common mode voltage.
Is there anyway you can increase the high voltage the sensor outputs? 10 V is pretty close to the 10 V minimum required between Vin and COM to register an ON state.
Ames
Applications Engineering
National Instruments

FP-CTR-500 don't read external count inputs

Similar Messages

Maybe you are looking for