Section 4 Binary input and output modules4.1 Binary input4.1.1 Binary input debounce filter GUID-AE43976C-E966-484C-AF39-89B2B12F56DC v5The debounce filter eliminates bounces and short disturbances on a binary input.A time counter is used for filtering. The time counter is increased once in amillisecond when a binary input is high, or decreased when a binary input is low. Anew debounced binary input signal is forwarded when the time counter reaches theset DebounceTime value and the debounced input value is high or when the timecounter reaches 0 and the debounced input value is low. The default setting ofDebounceTime is 1 ms.The binary input ON-event gets the time stamp of the first rising edge, after whichthe counter does not reach 0 again. The same happens when the signal goes downto 0 again.4.1.2 Oscillation filter GUID-41B89E6F-50C3-44BF-9171-3CC82EB5CA15 v4Binary input wiring can be very long in substations and there are electromagneticfields from for example nearby breakers. An oscillation filter is used to reduce thedisturbance from the system when a binary input starts oscillating.An oscillation counter counts the debounced signal state changes during 1 s. If thecounter value is greater than the set value OscBlock, the input signal is blocked.The input signal is ignored until the oscillation counter value during 1 s is belowthe set value OscRelease.4.1.3 SettingsGUID-07348953-4A72-444B-A31A-030ABEA8E0C4 v1OscBlock must always be set to a value greater than OscRelease. Ifthis is not done, oscillation detection will not function correctly, andthe resulting behaviour will be undefined.1MRK 505 394-UEN A Section 4Binary input and output modulesLine differential protection RED650 2.2 IEC 59Technical manual
