Attributes Of A Digital Input For Feeder Terminal Configuration - ABB REF 54 Series Technical Reference Manual, General

1MRS750527-MUM
5.1.7.5.
Feeder Terminal
Technical Reference Manual, General

Attributes of a digital input for feeder terminal configuration

The validity of the digital input (invalidity), the state of the input (value), the time
tag for the state change (time) and the counter value of the input can be issued for
each digital input by the attributes BI#IV, BI#, BI#Time and BI#Count, where #
denotes the number of the input. These attributes are available in the feeder terminal
configuration and can be used for different purposes.
The example below shows how the attributes of the digital input 1 (PS1_4_BI1 on
PS1 module) of the feeder terminal REF 541 are named for the configuration:
PS1_4_BI1IV; digital input invalidity
PS1_4_BI1; digital input value
PS1_4_BI1Time; time tag
PS1_4_BT1Count; counter value
Invalidity (BI#IV)
When a digital input oscillates, the invalidity attribute IV changes to TRUE (1) and
the input is blocked. The digital input is regarded as being blocked and oscillating if
the number of state changes per second exceeds the set "Input osc. level" value
(events/s).
When a digital input does not oscillate, the invalidity attribute IV changes to FALSE
(0) and the input becomes operative. The digital input is regarded as being operative
and non-oscillating if the number of state changes per second is less than the set
"Input osc. level" value minus the set "Input osc. hyst." value (events/s).
If the digital input is used in counter mode, IV is always TRUE (1).
Value (BI#)
Depending on the state of the digital input, the digital input value is TRUE (1) or
FALSE (0). The BI# value changes on the rising or falling edge of the input. To
prevent undesired state changes of the digital input due to for example switch
debouncing, the change of the attribute value is delayed by the filter time.
The value attribute of the digital input is not updated when the input is programmed
as counter digital input.
Time (BI#Time)
Each change (rising or falling edge) detected in the state of a digital input is time-
tagged at an accuracy of ±1 ms. The time tag represents the moment (time) of the
latest input change of the value attribute. The time is not recorded until the filtering
time of the state change has elapsed, which means that the filtering time does not
affect the time tag value.
Count (BI#Count)
The count attribute indicates the number of positive input transitions of a filtered
input. Refer to section "Pulse counters" on page 45.
The counter attribute of a digital input is not updated when the input is programmed
as a normal digital input.
REF 54_
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