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Control of AC Motor through VFD with Modbus communication via Labview

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Thank you very much Nahman. I am trying my vi right now but of course I will take a look at yours.

Thanks!

Alex

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Message 11 of 35
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Dear GerdW,

Attached you can find my final VI and a YouTube video of controlling the VFD via other software as an example. I have changed the addresses as the manual is giving but still I havent used anywhere the manual data from page 128 - 136.. Should I add more addresses for those? The Addresses that I have add are from the attached video..

Again, thank you.
https://www.youtube.com/watch?v=Yst9iJ6xfgc&t=9s

Alexis_Koul_0-1592295725883.png

 

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Message 12 of 35
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Hi Alexis,

 


@Alexis_Koul wrote:

Attached you can find my final VI and a YouTube video of controlling the VFD via other software as an example. I have changed the addresses as the manual is giving but still I havent used anywhere the manual data from page 128 - 136..


In the VI shown in the image you only set some basic parameters (serial port, command source, local address) in this loop.

Why do you think you need to set those parameters in a loop, again and again?

There is no command to actually set some process parameters, like motor speed, speed ramp up/down settings, motor specific data (like current at default working point, default frequency, etc.), safety parameters (P5), !?

 

I guess you created some (hardware) safety features in your testbench to prevent disaster in case your LabVIEW VI doesn't work as intended?

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
Message 13 of 35
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Dear GerdW,

I have also the following data, but I am not sure how to write them in the VI. For example for Commands of VFD. I will put address 06 and then input data which part? I am not sure how to combine the parameters address and the function description.

Then I need also to add in the same way for Monitoring the VFD (read frequency, motor speed, etc).

Alexis_Koul_0-1592307878572.png

Alexis_Koul_1-1592307937951.png

 

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Message 14 of 35
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Hi Alexis,

 


@Alexis_Koul wrote:

I have also the following data, but I am not sure how to write them in the VI. For example for Commands of VFD. I will put address 06 and then input data which part? I am not sure how to combine the parameters address and the function description.

Alexis_Koul_0-1592307878572.png


The shown table says: parameter address/register 2000h, values from 01H to 09H. That "command to VFD (06H)" denotes the Modbus command type.

The same applies to the other table: Modbus command type "03H" to read several registers/addresses…

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
Message 15 of 35
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Thanks GerdW. You have been very helpful and I am grateful for that.

I will input the address and the value for some parameters and then I will test it.

So the Command to VFD (06H) doesnt need to go anywhere?

-Alexis

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Message 16 of 35
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Hi Alexis,

 


@Alexis_Koul wrote:

I will input the address and the value for some parameters and then I will test it.
So the Command to VFD (06H) doesnt need to go anywhere?


The "command" is used for creating the Modbus message, see here.

Basically you are reading/writing analog output holding registers…

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
Message 17 of 35
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Hey GerdW,

Thank you for the link. I find great difficulty to understand it, mostly with the Commands to VFD and specially for the Monitoring VFD since there are only addresses and not values. In your previous comment you mentioned that I havent input any data such as motor speed, current or default frequency.

 

Not sure if I need to use the Commands to VFD or Monitoring VFD or both since the motor speed is control from the frequency..

-Alexis

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Message 18 of 35
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Hi Alexis,

 


@Alexis_Koul wrote:

I find great difficulty to understand it, mostly with the Commands to VFD and specially for the Monitoring VFD since there are only addresses and not values.


Those "monitoring VFD" values are entities you want to read from the VFD, so you need to send a read request with the register address to be read. The response of the VFD contains the register address and its value - as described in your manual!

 


@Alexis_Koul wrote:

In your previous comment you mentioned that I havent input any data such as motor speed, current or default frequency.

Not sure if I need to use the Commands to VFD or Monitoring VFD or both since the motor speed is control from the frequency..


You need to send a command with the speed/frequency the VFD should output. I don't see this in the image…

Best regards,
GerdW


using LV2020 on Win8.1+cRIO
Message 19 of 35
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Hello GerdW,

I have added some parameters as you suggest it. The <<Monitor VFD>> is 03H, and I have added the most important parameters as you can see in the image. But initially, I have add also the <<Terminal Protocol>> which was from P3.00. Will it make a troubleshoot with the terminal protocol because is also 3?

Is this schematic more correct than the previous?

Alexis_Koul_0-1592320396153.png

 

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Message 20 of 35
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