Kaulquappe

Hello Chintu,
when a slave responds with exception 2, the master tried to access an address which is not available. Have you got a link to the manual of the relay or can you attach the manual here?

Regards,
Kaulquappe

 hello,

thanks for reply.

i am attaching here a link of a manual of relay.

--Deleted Link--

need help.

thanks again.

Kaulquappe

Hello Chintu,
this manual show in section 4.3 the register / coil addresses from the application layer point of view.

Modbus RTU for CP341 uses the addresses of the data link layer as defined in the Modbus specification. So you must subtract 1 / 10001 / 30001 / 40001 from the ARGUS list.

When you use input register 0 length 0F you read half of a double word. I think this is causing the error. So use address 0 and length 0E of 10.

Regards,
Kaulquappe

 Hello sir,

Still have an error of exception code 02.

"Subtract 1/10001/30001/40001 from argus list,"

It means I am trying to read one data having address 30010, so I have to enter 0009 ??

Am I right??

Thanks

Kaulquappe

Chintu_661

It means I am trying to read one data having address 30010, so I have to enter 0009 ??

yes

Still i stuck on my issue. it is not resolve.

I tried 0,9,59,63,111,117 as a starting adrress for read data,but not succeed.

Thanks.

Hello,

for first, read input register from address 30001 use FC4 not FC3. You need change your value in your MB cfg DB to 4. Pls check also if you can poll number of registers as you required (simply if same type of registers are available), f.ex. you want poll from 30001 start address (address 0 in your MB cfg DB) 10 registers, but Slave maps only 5 registers f.ex. In this case Slave also return excp code 02, simply you can request only for 5 registers. This is only example when excep code 02 can also be returned from Slave. Other useful infos you have already from Kaulquappe. Don't hesitate ask other questions.

Update: pls pay attention also to have enough big recv buffer for requested amount of data due type - WORD/DWORD/... This can be also problem.

Duris_I

Hello,

for first, read input register from address 30001 use FC4 not FC3. You need change your value in your MB cfg DB to 4. Pls check also if you can poll number of registers as you required (simply if same type of registers are available), f.ex. you want poll from 30001 start address (address 0 in your MB cfg DB) 10 registers, but Slave maps only 5 registers f.ex. In this case Slave also return excp code 02, simply you can request only for 5 registers. This is only example when excep code 02 can also be returned from Slave. Other useful infos you have already from Kaulquappe. Don't hesitate ask other questions.

Update: pls pay attention also to have enough big recv buffer for requested amount of data due type - WORD/DWORD/... This can be also problem.

Hello,

First of all thank you for giving valueable tips.

My issue resolved after using FC04 and there was a problem regarding data polling. But, that resolved now.

and i can communicate succesfully with devices including both 7SR11 and 7SR12 relay.

One thing i observed that voltage parameter is not showing on 7SR11 relay's local display and also, can't get it on MODBUS RTU. but, in 7SR12 realy, There is showing voltage parameter on Relay's local display and on MODBUS RTU, also. Current's parameter are showing in both of relays.

Thanks once again. 

Hello,

glad that you have good results. Don't know realy where is the problem with show your requested value. Look to documentation of relay, maybe it's only case of configuration. Also in documentation is this table (attachment).