Function description
Operating Manual PSS u2 P0 F/S EIP
1004528-EN-03
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4.7
CIP Safety
System limits
The process image for the FS modules always occupies at least 1 Byte for the FS input or
FS output data, even if all the bits are not used. This results in the following system limits:
}
A maximum of 12 FS modules can be used
}
A maximum of 4 FS input modules of type PSS u2 EF 8DI can be used
}
A maximum of 8 FS output modules can be used
4.7.1
FS process image of inputs
In the process image of the FS inputs, the Combined Input Status (CIS) is used to indicate
whether all FS input modules supply valid values.
}
CIS = 0: Not all FS input modules supply valid values
}
CIS = 1: All FS input modules supply valid values
In the process image of the FS inputs, the Combined Output Status is used to indicate
whether all FS output modules deliver valid values.
}
COS = 0: Not all FS output modules deliver valid values
}
COS = 1: All FS output modules deliver valid values
From byte 10 the process image of the FS inputs is used for the valid bits of the FS output
modules.
Maximum length of the process image of the inputs: 18 bytes
INFORMATION
In the event of an input error, the valid bits for all inputs of all FS input mod-
ules are set to “0”.
In the event of an output error, the valid bits for all outputs of all FS output
modules are set to “0”.
Process image of FS inputs (for digital FS modules with up to 8 inputs or up to 8 outputs):
Byte
Bits
Meaning
0
0
Combined Input Status (CIS)
1…7
Not used
1
0
Combined Output Status (COS)
1…7
Not used
2…3
0…15
FS-PII of the first FS input module (data and valid bits)
4…5
0…15
FS-PII of the second FS input module (data and valid bits)
6…7
0…15
FS-PII of the third FS input module (data and valid bits)
8…9
0…15
FS-PII of the fourth FS input module (data and valid bits)
10
0…15
FS-PII of the first FS output module (valid bits only)
…
