CompactLogix Modbus

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Hello All, I have a controllogix PLC (L35E) using the ModbusMaster.acd file supplied with RSLogix5000 version 13. I have a Modbus network working on a RS232 network. The RS232 port of the compactlogix is connected through a DB9 crossover cable to my laptop with a modbus simulator (modbusview). I am simulating the PC as slave node. the PLC Master polls the PC slave and retrieves data from registers 0-100. This works fine. However in my application i wish to poll a device with address 2001. I am unable to do this because the following tags for registers 03 and 04 of the Controller Tags is limited to 250 words. Mod_Data_InpReg3 Type: INT[250] Mod_DataHoldReg4 Type: INT[250] QUESTION : when i try to read an address above 249 (03 or 04) the statement is not sent . I can see the statement is not sent because the PLC comms light stops flashing. When i change the address to 247 however it polls correctly and it retrieves data from my PC slave node. So to summaries I cannot poll data from a slave node above 248. Has anyone encountered this problem? Is this a limitation? I believe it may have something to do with setting the array larger than 2500 so that the data at address 2001 can be stored?