Siemens TC12 Installation, Commissioning And Maintenance Handbook page 115

Note 1.Only one of the above input types must be configured.
Note 2.The 32 inputs are numbered 1 to 32 in section 3.2.3.5, corresponding to
the associated pin on the 40 way input connector, however the handset
command numbers the inputs from 0 to 31, for the 32 inputs.
666/HE/43100/000
TC12 Installation, Commissioning & Maintenance Handbook
KFD 1 = (input number: 0 - 31) (255 to disable).
This allocates a mains state input driven by the actual flashing
supply.
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