I would like to display cold rooms temperatures on ABB automation system. York, supplier of Cold rooms has proposed to use the Modbus protocol defined as follows,
"The protocol used to communicate with the cold room controller is a subset of MODICON MODBUS (MB 1), only function codes 03 and 06 are supported.
Data are exchanged in ASCII slave mode (Cold room controller acts as slave) in the following format: Baudrate: 9600, Data bit : 7, Stop bit: 1, and Parity: Even."

ABB automation tell me that it is impossible to communicate because York do not support modbus function code 08 and this function is essential when ABB is the master in the communication and
unfortunately they cannot disable it.

York confirmed they cannot not be configured as master and cannot support function code 08.

Does any specialist here know if there a solution to fix this lack of communication between York and ABB? (Converters, software..)

 

Maybe a PLC in the middle, which would act as master to York's slave. I take it the ABB device can be either master or slave, so mastering on that network would be up to you to decide. I dont know if Modicon's current generation has any processors with two Modbus [not plus] ports, but if not you can use a SLC with a MCM card from Prosoft. These have two ports both of which can be either master or slave. There's even a pass through mode, but I don't think that would help if your existing master wants to use function codes not supported by your slave. I know Omron has communication processors for their PLC's which are very easy to configure, but I don't know if they support Modbus without some heavy lifting on your part. Another option might be an SST X-Link box with two Modbus cards.


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Steve Myres, PE
Automation Solutions
(480) 813-1145

 

Hi Stan

FieldServer Technologies has multiple port communication bridge FS-B4010-01 which can have master or slave loaded on any of the ports, the data can then be mapped from the one port to the other, this unit has solved many applications similar to what you have at present, have a look at www.fieldserver.com for more details on this product.

Thanks,
Richard

 

You have not mentioned the type of controller you are using,the E-prom in the Modbus card to be changed to disable function code 08.
contact ABB to have older version of E-prom

with regards
P.Narendrakumar

 

A possible solution for your problem would be to use a protocol converter module connected between the ABB master and the York slave(s). The MARC Omnii-Comm is such a device. You can review a spec sheet here http://www.miille.com/din266-p00.pdf or contact me for more information. This unit does support Modbus FC 08 for readback (echo) testing. You are welcome to contact me on or off list at [email protected] if you have additional questions.

Jerry Miille
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Jerry Miille
Miille Applied Research Co., Inc.
1730 South Richey
Pasadena, Texas 77502

713-472-6272 (voice)
713-472-0318 (fax)
Jerry Miille