Omron E5CC Temp Controller Modbus Reading Registers

[Merlin_NK]

I'm new to Modbus and I'm having trouble communicating with my Omron E5CC temp controller via RS 485 and Modbus.  I've downloaded the free LV Modbus library and I believe I'm using the proper RS 485 comm spec's.  I created a simple vi (create serial slave, read holding registers, slave shutdown) to read the PV. I can't figure out what "starting address" I should use to read the PV.  In the end I need to read and set the temperature.  The Omron manual refers to "reading variables" is that the same as "reading registers"?  

Seems like the addresses in the Omron manual are in HEX should I use "RTU" and input the addresses as HEX or is LV doing a conversion in the read registers block?  I'm worried I'm not using the proper address format or number system.

Is there any command I can use to verify I'm communicating with the device to isolate the problem to just identifying the right register?

Any help would be appreciated I realize it is hard to help without the hardware.

[ks30]

Hi Merlin,

Unfortunately the free Modbus APIs aren’t officially supported. Would you happen to have access to either of the paid options?

Modbus I/O Servers
http://zone.ni.com/reference/en-XX/help/370622M-01/lvmve/dsc_modbus_using/

Modbus VIs
http://zone.ni.com/reference/en-XX/help/370622P-01/lvmve/modbus_pal/

If the free API is using VISA calls under the hood (which I believe it is), then you could utilize I/O trace to look at the actual commands that are being sent to your device:

Performing a Good NI I/O Trace Capture for Debugging/Troubleshooting
http://digital.ni.com/public.nsf/allkb/282C5D41E2BA04F2862574BA007803B9

Additionally, is there a third-party utility that you could use with your device? It would be a good test if the to see if you can read registers using the manufacturer’s software independent of this API.

Finally, this table talks about the data model used in Modbus:

Modbus Data Representation (DSC Module or Real-Time Module)
http://zone.ni.com/reference/en-XX/help/370622M-01/lvmve/modbus_data_representation/

Regards, 

Kyle S.
Applications Engineer
ni.com/support 

[nguyenxuanthai]

Hi Merlin,

I can connect and run E5CN tempt. controller to Labview through Modbus.

Attached files are  my  programming test for E5CN. 

 I hope these files can help you.

[kirit0101]

it is very easy

first use h2000 for pv read

h2103 for write sv

this two is main for you for mod bus address for set temperature

like for mitsubishi plc

command is

adprw h1 h3 h2000 k1 d100 m20

adprw h1 h6 h2103 k1 d102 m21

mov set pint to data registor

use related cmnd for related plc like for delta it is modrd or modrw

[Kathir_rkv]

Thankyou So much Bro.. It is very useful to me on my project.

[bombax123]

Hello, thank you for the source file. However, I am facing a problem regarding setting the point. Ive tried to put the address but the command doesnt seems to register the address... hope you can help me on this... thank you

[StevenD]

Hello bombax,

What have you tried regarding setting the SP?

The first posts in this tread were authored quite a while ago. There are now officially supported Modbus libraries, specifically this , and this (there may be more)

I like the first one, but it does not allow for 7 data bits and  2 stop bits so you would have to change the settings on the device (8E1 are the required support settings)

If what you have is working for reading registers and want to use it, I'm a fan of things that work. You just need to know how to send a command that the device will recognize (device address, function code, data, and crc) which are documented in the pdf linked earlier.