Modbus tcp read holding registers return not requested quantity

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• LabVIEW Modbus TCP with VFD. Could not establish connection / error 56? Any thoughts?

  Hello

  I'm trying to establish a connection to a VFD (Variable frequency drive) for academic research, for testing purposes. My implementation consists of:

  ---> LabVIEW (Master)

  ---> ABB ACS880 VFD (slave) with adapter from Fieldbus FENA-01

  ---> (ABB motor induction)

  ---> (Internal Combustion Engine)

  First of all, I'm new to Modbus TCP protocol, but I went through all the white papers of NOR, I have read and followed all the instructions from the manual of the VFD and the fieldbus FENA-01 adapter manual. I'm also pretty new to LabVIEW, but I'm confident, I have the knowledge to create the necessary VI.

  I created a simple VI who would be able to read some registers the VFD, which is attached below. The VFD is connected by Ethernet to network local ethernet and the Master PC is connected to the same network. When I run the VI, 56 error, which as I read from other messages of the forum is to not get answer within the given time.

  I tried the things:

  --> Check all cables are connected properly

  --> Double check the manuals

  --> Checking the FENA-01 in the chassis, which gives the indication of waiting for query modbus

  --> Looking for a gateway IP address, but I did not find, so I expected, I don't have to add it to the VFD parameters

  --> FENA-01 refreshing settings that always translates to "offline" status

  -->, I also checked in Labview > tools > Options where you check TCP/IP and there no port 502 written but I do not change it cause I had to leave the laboratory at the time. The port number was something like 3363 (something like that again)

  Issues related to the:

  --> Do I need to specify a new device somewhere in LabVIEW or in the control panel?

  --> What I need to create a separate VI to make the connection?

  --> What 'send 1150 for operating loan' and ' send 1151 for operation "means the control word?

  I would be very grateful if someone had information about this before the end of the week. I'm running tight on my period and I just can't stand this VFD with the limited power of the local command of monitoring mode.

  Thanks in advance for any help.

  Neo

  Hello, the problem is solved, and this could be a solution to problems like these.

  The IP address of the car was not on the same network as the Local Ethernet network connected to it. The IP address of the disk was 192.168.0.16 and the network was on 192.168.1.1. Once the IP address of the network changed to 192.168.0.1 communicated properly.

  I also have ping after and showed the communication.

  Thanks for the reply TST.

  Peace,

  Neo

• Control PLC Modicon-Quantam of Modbus TCP/IP Ethernet.

  Has anyone use LabVIEW to program a PLC Modicon-Quantam successfully using Ethernet TCP/IP? I tried the examples MB Ethernet (master/slave) in the download nimodbus121 and it doesn't work. I really need to know the best way to connect and communicate to a PLC Modicon-Quantam using LabVIEW, Ethernet Modbus TCP/IP using the Excel spreadsheet. I need to write entry registers (write) shift in and read from holding registers. The software that I SMTX Modbus/TCP Master control ActiveX does not completely for me. I can ping to the controller from cmd prompt. I saw this webcast - creating a server of e/s Modbus TCP with the LabVIEW Datalogging and supervisory Control Module 8. I've also seen a webcast on OLE for process control (OPC). What should I write LabVIEW control and view records by using LabVIEW flags? Someone at - it a LabVIEW example that I can start with? Should I buy the DSP module for $1280,00? This will solve my problems?

  If you have found return data that you do not understand that I recommend trying to send output known of the automaton at least to determine what kind of conversion has to happen. This document talks about the Optomux protocol that can be used with programmable automata. You will need to find specific documents that tells you how to convert these data into LabVIEW. You can also start a new forum, since this is a separate issue from the original.

  -Hunter

• need to read siemens S7 i/o in labview via Modbus/TCP

  Hi friends,

  We are developing an industrial project and facing a scenario in network as follows...

  Abt Project brief

  Its a treatment to the sweage plant. We use the NOR-PAC and Labview version: 8.5.1 for process control. We got a few 3rd e/s Party which must be monitior in Labview.

  Details of 3rd party

  -Siemens S7 - 200 with EM 277

  In our factory in the entire network is fo - TCP/IP. Now, we must take Siemens of e/s via TCP/IP in labview. To what extent this can be done. If it has to do with Modbus/Profibus converter can we do the configuration online without distrubing plant.

  Thank you & best regards

  Pravin Moussa

  Systems engineer

  Hi Pravin

  I am not sure of your diagram exactly what is your network. You have shown a link of the FO-tcp-ip for the S7-200. How does this happen? Or did you ask here, to work on options?

  Since the S7-200 can be slave profibus DP through the 277, it won't 'see' some other profibus IO anyway. You can use a Siemens CP243 module to give tcp - S7 - 200 ip connectivity. Also, is there a connection of profibus S7-300 and S7-200, all e/s of the S7-200 can be mapped to the S7-300, so you only need to worry about communicating with the S7-300.

  Another option

  Regarding modbus, they charge a lot of money for the Step7 from siemens modbus library. On the other hand, the S7-200 comes with a free modbus library, but it's the modbus RS485, not modbus tcp - ip series. Perhaps you could use this and use one of the many series-to-ethernet doors available.

  -Michael

• Strange signal Modbus TCP/IP

  Hello everyone:

  I am facing a strange problem on the modbus TCP/IP communication, we have built the connection and use the modbus library OR read the analog signals, it works, but the return signals seems odd, for example (A 40-0 for value: 5, 3F80 for value: 4000 to 1 and 2), I went throngh modbus specification documents , but in these values do not respect the rules, is there anyone has idea about this?

  Thanks in advance.

  Best regards

  Are you waiting for floating point values? Modbus transfers bytes. It's the software front end to convert the bytes floating-point or of other signed/no signed integer values, 32-bit integers...

• You can trigger through communication Modbus TCP/IP PLC data acquisition without using a loop for?

  Hello

  I am trying to contact a facility through a Modbus TCP/IP communication PLC. I'm new to this method, but the idea is that the installation will send the logical (Boolean) values 1 bit by ethernet to my workstation which read and then will begin data acquisition. Basically, I need a triger to come to my pc. I placed my vi inside a structure case T/F which will run according to the signal, it receives data acquisition. However, for it constantly waiting, I put this in a loop for. The works of vi, but playback signals sometimes lagging behind due to the loop for. If I take the loop out and just run labview permanently, it works perfectly, but I know that the option is only for debugging and should not be used. So my question is, is there a better way to wait for an incoming signal?

  Hello!

  Please note that the order of execution of the write operations on the shared variable 000002 is not determined.

  For example, nothing prevents this order of execution:

  (1) value false 000002

  (2) set to true 000002

  (3) execution of the loop

  In what concerns the delay, you might consider placing a waiting vi in the case of 'false', or the loop uses 100% of CPU if I'm not mistaken...

  Kind regards

  Marco

• Modbus/TCP connection to the controller of power Eurotherm EPack

  There are examples of how to connect to a power controller Eurotherm EPack a modbus/TCP connection?

  I downloaded the Modbus LabVIEW ni_lib_modbus_library library - 1.1.3.32.vip and installed using VIPM.

  However, I am not familiar with the Protocol modbus and terminology such as coils, keeping records.

  I can't even properly run examples for Modbus master and slave to this library :-(

  Most important for me now is just to read the value of the artwork process.

  "ITools" Eurotherm controller software provides information about something I think are an address of memory the value of process I want to read.

  However, I have no idea how to set the various parameters to get successfully connect and read the value of the process.

  Trying to solve my problem, I managed to have basic communication and engineering data conversion.

  Now I can read values of process as the power line frequency, voltage and others.

  Once you know, it's very simple (once you have the modbus library)

  Some things that remain unclear:

  -What values are 32-bit and 16-bit?

  -is the method of addressing identical for all parameters?

  -is it the same for reading and writing?

  I would like to be able to write the target value, for example.

  I'll contact the seller for these outstanding issues. The manual is not really clear (at least not for me). He mentions that some values may be treated differenly (they 16bits, but globally, so 5001 with a scale factor of 100 means actually 50.01 for example).

  See the attachment for reading cover base.

• How fast can get a TCP read?

  LV 2009 + WIN 7 with 6 GB of Ram.

  I acquire two analog channels as a word of 16 bits each and adding a CRLF at the end example: 1234 567 \r\n

  These data are acquired to 50ms intervals and sent over a link WiFi for my notebook running code LV.

  I know not how fast the "TCP - Read" function can work and which mode (it has four options) to choose if I do not miss any incoming data...

  Now I get some data in French - initially rather quickly and after a few seconds, it slows down the consdierably. I'm running the TCP-read inside a timed loop and I tried various intervals from 10 ms to 500ms. The largest value works OK, but I need the fastest possible. Tips how to handle this?

  My code is attached. (The passage DIO works very well)

  Even if the passage DIO works, it doesn't make sense to use a sequence structure.  It would be better to change the Standard mode and the 100ms Timeout value instead of "wait for next"millisecond"Multiple" as leading to uneven wait times.

  TCP Read should run very quickly, subject to any waiting period that you set.  You should never lose data in any mode, although there is a possibility to receive a partial when you use Standard mode or immediate (unlikely in your case since you read so little data).  The operating system will be buffering of data not read for you.  If you want the fastest possible exchange, divide your code in two while loops, one for EID and the other for the series.  Serial communication can be simply a normal life while loop, with the reading of TCP dictate the timing.  Set a long timeout in buffer mode and the loop will run as quickly as it receives data.

  Also, when the loop ends, you must close TCP connections, not just one of them.

• Stop the Modbus slave server works if have the request to address 0 frame (from

  Stop the Modbus slave server works if have the request at the address 0 (broadcast massage) frame

  Hi alexart,

  How do you define the address 0? When I put my server Modbus slave address 0 in the communication parameters, it is by default to 1, so I am not able to change the address 0.

  In addition, the server does not work? What is happening and how do you know? Is there an error code, or what else is happening?

  Kind regards

  Stephen S.

• LabView TCP read

  Hello

  I'm reading the data from a personal weather station which is transmittng data to a web site using a bridge.  I can see the data transmitted with WireShark, so I know the bridge works and the data is there.  Also the data are learning web site.

  I want to read that data, using LabView, it is sent to the web site.

  I tried the TCP connection open with the TCP Read function and also the TCP Listen.vi with the TCP Read function without success.

  I have attaced the two screws and also a page of WireShark.

  A question I have is how do I know what port to monitor?  It continues to change in WireShark?

  Any help is appreciated.

  Perry

  TCP in LV functions are not sniff the functions. They are used for the direct connection from point to point.

  If the web site supports getting data back, you can try to contact and to read the data in (probably use the HTTP or web service screws, according to the API provides the site).

  Otherwise, you could try to imitate the BT site and having the unit send you data, but probably the address of the site is hard coded into the device. You could probably play with it to feign a DNS server which will redirect to your computer, but you should always know what the API to send data on the site.

  A third option is to do the desired sniffing. LV has no functions for this, but you can find wrappers that people wrote for WinPCap, that might do what you want. I've never used, so I don't know.

• Modbus tcp 1.2 problem with labview 8.5

  I have a new upcoming project that involves a link to modbus tcp.  I downloaded version 1.2 of the modbus library and installed.  Everything appears on my palette, but if I try to open one of the examples he comes as for version 8.6.  I am currently using 8.5 but the download says it works all the way back to 7.1.  Any ideas?

  Are you sure that you have selected the correct folder for the "installation"? When you download the 1.2 OR Modbus Library (here: http://zone.ni.com/devzone/cda/epd/p/id/4756), you get a zip file. Inside this file, you will see 4 folders, one for LabVIEW 7.1, (issue 71), one for LV 8.2 (case 82) and also records 85 and 86. So make sure that you have done the installation with the correct folder.

  Let us know if this helps or not.

  Kind regards.

  Robst.

• interpretation of TCP read the output string

  What is the right method to interpret the data from the TCP Read function? The output is a string of characters, which are obviously not hexadecimal values. How can I convert the string to a binary table or bytes?

  OK, time wild guess...

  The first four bytes are an indication for SYNCHRONIZATION

  The four bytes 0 4 0 0 is a 32-bit integer, GIS bytes less first. 1024

  Then you have 6 0 0 0, which could be another 32-bit integer, lsb first. 6

  Then your random data

  Rod.

• change comm driver for koyo modbus tcp

  I have a working system that uses a koyo plc and modbus driver.  I change to the controller for a scadpak with modbus tcp.  Is it possible to switch the comm driver without having to recreate all the tags and the screens that were created under the former comm driver?  I know I have to change registers views use to reflect the scadapak controller, but I hope I don't have to start!

  OK, I got it work.   I created a new modbus ethernet driver.  Then I exported an empty xls file to this new driver.  I then exported a xls of the FORMER pilot with the old information.  With the two spreadsheets open, I then cut and pasted the old news into the new xls file.  Then, I changed the former membership numbers for the new numbers, which I used with the new PLC.  It WORKED!   I think it is best when you change the PLC.

• Cannot start/open new Premiere Pro trial - error flag reading - on demand could not start properly _ 0c000001d click OK to close the application

  Dear Forums

  Cannot start/open new Premiere Pro trial - error flag reading - on demand could not start properly _ 0c000001d click OK to close the application

  * Also, I sent my first question 20 minutes ago, not yet approved? Your return indicated "approved" e-mail, * why do I not see my question below still displayed? >

  The members of the Forum Pro first - Hello
  

  
  

  Can someone out there describe in simple basic procedure, how a first time user start using Premiere Pro to the layer just a moving figure video of 5 minutes (a friend aerial artist model with white moving belt in silk on a rest mainly black background layer and a change to a night sky stars panorama I photographed previously?)

  I know that this can easily be done, I have worked in thousands of still images with creative cloud for previous years, but not yet in video in Premiere Pro, so thanks for any advice.

  I enclose the actual video that I use and some samples of the fields of the night sky that I photographed recently for ideas

  I intend to make possibly more elaborate, but for now if anyone of you could just show the basic commands and menus/menus to start to do it simply and quickly. Maybe how to most later convert it tone black & white or sepia. The ideas here is to recreate a sequence modern suite of familiar German Film, wings of desire. Perhaps also a progression in the future to create an effect of the night sky very slowly turning into one layer background behind the main façade first video layer in normal movement. Then maybe a little further - how to adjust the speed of the front to a path layer more slow half price while keeping the substantive motion, the original speed. (* although I realize that I didn't do in 64 fps for the slow movement, I am not concerned about that and would actually welcome a light old world "flip effect framework" as if, in appearance of the films more former silent motion.) * In addition, possibly cutting on 'dead time' a few seconds at the beginning of the video and the 2nd or 3rd time for a few seconds of this unexpected error, when the silk scarf fell on the camera lens (without changing the audio timeline?)

  * (I use Windows 7 on a Toshiba Satellite L555 - [only RAM 4 MB. rates], 2009)

  * Video sample >

  Sarah Seiler Aerial - camera Check-An Unedited manifesto-Dec 16 2015 - YouTube

  * Background samples >

  w-left-west-frames-with-earlier_sept-8_9-2015_1_stitch-mercator-projection-2a-titles-5000-pxl-b_galaxies-at-right-enlarged-5500-pxl http://www.dpreview.com/galleries/1579463287/photos/3374478/Trillium-Lake-Aurora-add-26-ne

  Comet Lovejoy Andromeda brand camera telescope DSC3857-1a-blue-light-increase-layer-Nov 20 2015: Mark Seibold: Galler...

  Larch Mtn Night Sky Sony NEX5R 5 Oct 2015_panorama point 2 b side of cropped rt 3000 pxl: Mark Seibold: galleries: digital...

  Cannon Beach Haystack Rock mamiya 55mm 25 2015_10_stitch_102 26 Aug frames Projection of Mercator Crop dark as he nu Fi...

  Trillium Lake Mount Hood Dark Night Sky Nov 10 2014_stitch a 5000 pxl f to fill 2: Mark Seibold: galleries: Digital P....

  Thanks so much for all the advice of one of you in the Adobe Premiere Pro forums,

  Mark E. Seibold, artist-astronomer, Portland Oregon

  Duplicate thread here: may describe in the simple basic procedure, how a first time user start using Premiere Pro to the layer just a moving figure video of 5 minutes (a model friend artist air with white passage belt mainly black silk )

  Thank you

  Regalo

• I am trying to record an mp3 file, but firefox does not allow me to save... it allows me to read the file but not download and asave to my computer. How can I enable to save the mp3 files on my computer?

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