Modbus libraries for LabView 8.0

[Brian_Beal]

I have done this using an OPC server and Labview.  The addresses are off by one.  For parameter 102, use modbus address 101.  Are you using the FMBA-01 adapter to communicate?

[BXPL-PoP]

Hi.

Yes, I am using the using the FMBA-01 adapter to communicate to the ACS350.

This part of the data gathering is just a small part of the test setup, but unfortunately it is taking all my time for the moment.

All I want to do is to read 4-6 registers to get the rpm, temp and other values from the motor connected to the motor drive.

I am also trying to get information on how to do this from the local ABB supplier. No luck so far.

Peder

[BXPL-PoP]

Hi again.

I played around with adress mapping and and stuff, and am now able to read registres.
But there are some funny stuff going on; Only specific combinations of start adress and # of registers works.

However I am getting transmitted the information I need for now,
and will dive into the nitty gritty details later when I (hopefully) have more time available.

Thank you all for helpfull information. Have a nice weekend.

Peder

[BXPL-PoP]

Hi,

Portmon was mentioned as a tool to check what is actually sent to and from the Modbus device.

Can anybody tell me where to get this or other similar sw to help me in debugging my application.

Peder

[Donald]

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@BXPL-PoP wrote:

Hi,

Portmon was mentioned as a tool to check what is actually sent to and from the Modbus device.

Can anybody tell me where to get this or other similar sw to help me in debugging my application.

Peder

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You can get portmon from http://www.microsoft.com/technet/sysinternals/utilities/portmon.mspx

[BXPL-PoP]

Tank you,

I got it installed and I am now monitoring what's passed back and forth.
My suspicions goes to the crc-generator.

Peder

[unclebump]

If you are doing a lot of communication work, it might be worth purchasing some hardware for monitoring the dataflow.

http://www.fte.com/products/Serialtest-01.asp?RKG=983859

http://www.fte.com/products/Serialtest-Sync-01.asp

http://www.blackbox.com/files/productdetails/20716.PDF

Also this one.

http://www.fte.com/products/FTS4Control-01.asp

http://www.fte.com

Message Edited by unclebump on 05-14-2007 08:06 AM

[RavensFan]

Have you tried reading each register individually one register at a time to see if it works?

Earlier you said  "Is there anybody that can point me in a direction? The motor drive adress is set to 1 and the registers I would like to read are 102, 104, 106 and 110." 

But here you are saying you are trying to read " # of regs:6 (or 10, or ...)"

Perhaps some registers in between don't exist on the device.  If you read starting at 102 and try to read 4 registers, perhaps #103 doesn't exist, or #105 and it is trying to read one of those non-existent ones as it tries to read a whole block of registers.  Motor controller manufacturers often use the same registers between their different models to be the same thing.  But sometimes they need to add a register for a new feature added to a new controller, or delete a register in a given model if that register is meaningless to the new model.

[BXPL-PoP]

Hi.

Thank you for the tip. There are holes in the list so that explains some of the errors,
but there are still broblems with combinations of start adress and number of registers.

Anyway. For now I am getting the needed information and log all vital data from the ongoing tests.

Thank you all for helping me out.

Peder

[gdah]

eloo..i need help plz..i want to write multiple data to SPR (system protection relay) by using modbus library. but there is some time out error occured when i try to write more than 1 data to the device. actually i am not really expert in using this library. i try to search any labview code example using this library in order to write multiple register in internet. unfortunately i can't find it..plz..anyone can solve this problem..