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 a millisecondwhen a binary input is high, or decreased when a binary input is low. A new debouncedbinary input signal is forwarded when the time counter reaches the set DebounceTimevalue and the debounced input value is high or when the time counter reaches 0 and thedebounced input value is low. The default setting of DebounceTime is 1 ms.The binary input ON-event gets the time stamp of the first rising edge, after which thecounter does not reach 0 again. The same happens when the signal goes down to 0again.4.1.2 Oscillation filter GUID-41B89E6F-50C3-44BF-9171-3CC82EB5CA15 v4Binary input wiring can be very long in substations and there are electromagnetic fieldsfrom 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. Theinput signal is ignored until the oscillation counter value during 1 s is below the setvalue OscRelease.4.1.3 SettingsGUID-07348953-4A72-444B-A31A-030ABEA8E0C4 v1OscBlock must always be set to a value greater than OscRelease. If thisis not done, oscillation detection will not function correctly, and theresulting behaviour will be undefined.1MRK 511 408-UUS A Section 4Binary input and output modulesPhasor measurement unit RES670 2.2 ANSI 73Technical manual
