Siemens TX-I/O TXM1.8D - Page 21

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Siemens TX-I/O™ Module system – Functions and operation CM110561en_08
Building Technologies Digital input functions 2018-10-25
• The multistate process value is mapped so that the mapping table specifies one or
more inputs to be active.
• It is possible to have several active inputs, but only in a fixed coding.
• Examples: Enabling additional electrical heating or burner stages
• If no input combination corresponding to the process value is found in the mapping
table, a Reliability Error message is transmitted (Quality = MULTISTATE_FAULT)
and the last valid process value stays active.
Active I/O points
MIValue
Stage
None
0
0
n
1
1
n, n+1
2
2
n, n+1, n+2
3
3
n, n+1, n+2, n+3
4
4
:
:
:
n, n+1, n+2, n+3, ..., n+7
8
8
• The multistate process value is mapped so that the mapping table specifies one or
more inputs to be active.
• It is possible to have several active inputs.
• Examples: Enabling additional electrical heating or burner stages.
Active I/O points
MIValue
Stage
n
n+1
n+2
n+3
...
n+7
0
0
0
0
0
0
0
1
0
0
0
0
1
1
0
1
0
0
0
2
2
1
1
0
0
0
3
3
0
0
1
0
0
4
4
:
:
:
:
:
:
:
1
1
1
1
...
1
255
255
• The I/O status LEDs indicate the activity of the inputs
• In the case of an error the module status LED and all the I/O status LEDs assigned
to the function flash.
Inputs cannot be operated on the module.
For details, especially in relation to flashing pattern and errors: refer to the section "Dis-
play, operation and diagnostics" in the TX-I/O™ Engineering and installation guide [6].
Up-down mapping
Binary mapping
Display
Local override