Hello

I have been configuring MODBUSPN V2.0 block with TIA portal 14 SP1 + 315-PN/DP and created successfully connection to VFD, but when trying to read data from modbus simulator made by battery manufacturer I receive error 8088. When I look communication with wireshark PLC receives message and even sends  [ACK] back to server. I just cannot read the data from PLC program and MODBUSPN shows error + status 8088. There was no issues using modbus poll to connect simulator.. 

This fault is not found from MODBUSPN manual what could be the issue ?

I found this description which could explain why data is not updated to correct DB. any way to disable LEN monitoring from MODBUSPN ?

"If you have specified the length of the data to be received (DATA parameter of FB 64 "TRCV") to be less than the length of the sent data, FB 64 will not copy any data into the receiver range but instead will supply the following error information: ERROR=1, STATUS=W#16#8088."

According to monitoring error comes from TRCV block, inside MODBUSPN, but cannot really understand what should be done in this case

I Looked wireshark logs while sending read request. PLC 192.168.0.1 and simulator 192.168.0.40 where is seen that simulator sends requested data to PLC without errors in this level. When looking at PLC application TRCV block status inside MODBUSPN block is 8088. 

• Receive area is too small

• Value in LEN is higher than the receive area specified by DATA

I will try to take only the modbus comm part from the project for testing

Sorry about long silence, I made a clean up to project and get rid off the error code. There was some initialization issues, and after successful init there no errors anymore. 

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