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Inversion Inputs DESCRIPTION A Digital Input may be configured to be read as ON when no voltage is applied to the input and be considered OFF when the LED associated with the input is actually illuminated. This is the case when the input is 'Inverted'. The inversion can be accomplished in two different ways. The input signal may be inverted as it is sampled by the system. It can also be inverted as it is reported by the system. The difference is in how other input features perceive the input state. Sampled Inversion The input Debounce, Latching, Counting, Metering, and Logging features operate on the input state as it is sampled. When Inversion is applied to the sampled input all of these features see and respond to the inverted input state. This is useful in accommodating an input signal whose voltage works with opposite meaning (5VDC means not active for instance). Conditioned Inversion When an application uses an input state in a sense opposite in meaning to the signal itself, it may be appropriate to invert the reported state. In this case input features work logically and the application is still satisfied. In this case the Inversion is applied as a form of state Conditioning prior to reporting. NOTES State Alarming reflects the reported state. Counting and Metering (Usage) alarms result from the sampled state. Both Counting and Metering can be configured to respond to either a '0' or '1' state. In effect these each have their own type of inversion. There is sufficient flexibility to accommodate whatever is needed. SEE ALSO HELP Topics: IO/Inputs/[DIN]/Inversion, IO/Inputs/[DIN]/Conditioning [/flash/manpages/registry.hlp:2492]