Area Length Error while reading

Instance DB. Double -Word access. Access address: 590

Request OB: Programming Error OB(OB121)

Priority Class:1

Internal Error, Incoming Event.

This was the Error in S7-300 PLC But Plc is running and showing SF Fault.

There was only one way communication missing............to S7-300 to s7-200  PLC.

we are able to transmit the analog values to s7-200 plc but unable to read the analog values of s7-200.

Kindly help.....

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Split from about SIEMENS PLC.

vrmkiran

 Area Length Error while reading

Instance DB. Double -Word access. Access address: 590

Request OB: Programming Error OB(OB121)

Priority Class:1

Internal Error, Incoming Event.

This was the Error in S7-300 PLC But Plc is running and showing SF Fault.

There was only one way communication missing............to S7-300 to s7-200  PLC.

we are able to transmit the analog values to s7-200 plc but unable to read the analog values of s7-200.

Kindly help.....

 Hello vrmkiran,

you should look at this address 590 in your instance DB, are you sure it exists?

PLC runs because you downloaded OB 121 in the PLC