Novatech Bitronics M87X Series, Руководство пользователя

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ML0021 August 15, 2018
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Copyright 2018 Bitronics, LLC
5.3 Triggering
Triggers can be configured in the 70 Series to initiate several different actions:
Waveform Recorders
Disturbance Recorders
Digital Outputs
Virtual Outputs
SOE Entries
Resetting of various measurements (Demands, Energy, etc.)
Up to 120 triggers can be specified, of the following types:
5.3.1 Threshold Trigger
Any measurement can be used to trigger a Waveform Recorder or Disturbance Recorder,
or create an entry in the SOE log. Configuring multiple triggers will cause a logical "OR" to
be applied to the list of triggers. The trigger thresholds are defined by the 70 Series
Configurator. The user specifies the measurement to use, the threshold value, the
arithmetic function of the trigger, and the hysteresis value.
If the measurement is an analog value (such as volts or amperes), the user may choose to
trigger on values greater than or less than the threshold. Additionally, the user may
choose a rate-of-change trigger greater than, less than, or equal to the threshold value.
Rate-of-change intervals are calculated over the interval since the measurement was last
updated.
5.3.1a Trigger Hysteresis
Hysteresis is used to prevent chattering of contacts or unintended repeat-triggering of
recorders when a measurement fluctuates near the value where the action is intended to
occur. Refer to the Hysteresis column on the
Recorder Triggers page of the 70 Series
Configurator program (below). The hysteresis setting is used to make the trigger occur
and re-initialized at different values. In the example below, since 60.3 Hz - 0.1 = 60.2 Hz,
the action takes place when frequency exceeds 60.3 Hz and re-initializes below 60.2 Hz.
When hysteresis is set to zero (default) the action triggers and resets at the same value.