10/10/2022 6:03 AM | |
Joined: 1/21/2013 Last visit: 5/7/2024 Posts: 2756 Rating: (445) |
Hi Chris, the service information at the parameter DIAG of the FDBACK instruction is bit-coded. The value 2 (dec) is 0000 0010 in binary system, so in your case the bit 1 (Passivation of F-I/O/channel controlled by output Q (= state of QBAD_FIO)) is TRUE. The cause is the parameter QBAD_FIO. For this parameter, the usage is a little bit confusing. The parameter should be TRUE if an error on the failsafe output channel was detected. For S7-300/400 for this, the QBAD parameter of the F-I/O DB is used. For an S7-1200/1500 you should use the value status instead. But, the behavior of the value status is exactly the opposite of QBAD. The value status will report an FALSE in case of a detected error. So you have to invert the signal on the parameter QBAD_FIO. Kind regards |
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