Hello Experts,

Could you help me with the MODBUS Master comunication..

My hardware is:

1. CPU: S7-317 2PN/DP (6ES7 317-2EK14-0AB0)

2. CP341 (6ES7 341-1CH02-0AE0) With the dongle of Modbus Master.

I  have to read  from a microtol Turbidimeter ( modbus RTU, adress 200, baud rate 9600 )

I look all the examples posted about this issue,

 https://support.industry.siemens.com/cs/attachments/99742134/zXX21_04_PtP_Com_MODMA.zip

I tried to using the MODBUS_COM_LOAD with MODBUS_MASTER blocks but i dont have results..

Please if someone can help to me, showing me an example, of a slave adressing as 200, and what is missing to my program

Best regards..

Raul Romero

Hello,

for first, you can't use your mentioned instructions. They are for S7-1x00 CPUs not for S7-300. You need use RK instructions, look to my attachment where you can find them.

Duris_I

Hello,

for first, you can't use your mentioned instructions. They are for S7-1x00 CPUs not for S7-300. You need use RK instructions, look to my attachment where you can find them.

Hello Duris_I;

Thank you for your response, I am triying with those functions you mentioned.. but I dont have results.

Could you explain me please how to use it?

Best regards

Hello,

you can look to this link:

https://support.industry.siemens.com/cs/document/109474714/master-slave-communication-with-modbus-rtu-protocol-for-s7-300-and-et-200s-systems?dti=0&lc=en-WW

Also as standard CP341 MB RTU Master manual can be helpful, there you can see what you need set to correctly receive data from Slave.

R_ROMERO

Hello Experts,

Could you help me with the MODBUS Master comunication..

My hardware is:

1. CPU: S7-317 2PN/DP (6ES7 317-2EK14-0AB0)

2. CP341 (6ES7 341-1CH02-0AE0) With the dongle of Modbus Master.

I  have to read  from a microtol Turbidimeter ( modbus RTU, adress 200, baud rate 9600 )

I look all the examples posted about this issue,

 https://support.industry.siemens.com/cs/attachments/99742134/zXX21_04_PtP_Com_MODMA.zip

I tried to using the MODBUS_COM_LOAD with MODBUS_MASTER blocks but i dont have results..

Please if someone can help to me, showing me an example, of a slave adressing as 200, and what is missing to my program

Best regards..

Raul Romero

 Have you downloaded Modbus Master driver into the CP341 ?

Hello R_Romero;

I agree with Panov69, you might have overlooked the required step to load the Modbus driver in the CP 341.

For this, you need the Setup_PTP package, that you can download from this FAQ:

Download CD 'CP340, CP341, CP440, CP441'

Also check section 4.7 "Assigning Parameters to the Loadable Driver"  of the Modbus master driver manual that was suggested by Duris_I in his earlier post

Hope this helps,

Daniel Chartier

With CP 6ES7 341-1CH02-0AE0 the Modbus Master driver code is part of the firmware. Only with older CP types it is necessary to load the driver.

Regards,
Kaulquappe

Kaulquappe

With CP 6ES7 341-1CH02-0AE0 the Modbus Master driver code is part of the firmware. Only with older CP types it is necessary to load the driver.

Regards,
Kaulquappe

I do not agree with you. According to CP technical data, integrated protocol data are 3964(R), RK512 and ASCII.

6ES7341-1CH02-0AE0

Regards.

It is a little bit difficult: the integrated protocols are these for which you do not need a dongle. With CP341-1CH02 it is not required to load the driver code - the driver code is part of the firmware, to activate it a dongle is still required. With CP341-1CH01 you needed to load the driver code as well.

Regards,
Kaulquappe

Kaulquappe

It is a little bit difficult: the integrated protocols are these for which you do not need a dongle. With CP341-1CH02 it is not required to load the driver code - the driver code is part of the firmware, to activate it a dongle is still required. With CP341-1CH01 you needed to load the driver code as well.

Regards,
Kaulquappe

 Sorry, my mistake I found a FAQ talking about that : Loadable driver CP341.