SATEC SA300 ezPAC Operation Manual - Manual (Page 80)

Chapter 7 Programming the SA300 Using Control Setpoints
80 SA300 Substation Automation Unit
The binary events are divided into two types: static events and pulsed events. Static
events are level-sensitive events. A static event is asserted all the time while the
corresponding condition exists. Examples are digital inputs, relays and internal static
events generated by the device diagnostics, metering procedures, and Power Quality
and Fault recorders.
Pulsed events are edge-sensitive events with auto-reset. A pulsed event is generated
for a trigger only once when a positive transition edge is detected on the trigger input.
The examples of pulsed events are pulse inputs (transition pulses on the digital
inputs), internal pulsed events (energy pulses and time interval pulses), and events
generated by the interval timers. The logical controller automatically clears pulsed
events at the end of each scan, so that triggers that used pulsed events are
prevented from being triggered by the same event once again.
Using Event Flags and Virtual Relays
The SA300 has 16 common binary flags, called event flags, which can be individually
set, cleared and tested through setpoints or remotely.
Event flags can be used in different applications, for example, to transfer events
between setpoints in order to expand a logical expression or a list of actions that have
to be done for a specific event, or to remotely trigger setpoint actions from the
SCADA system or from a PLC.
In the same way, any of the 32 device relays that is not actually present in your
device (it is called a virtual relay) can be used to transfer events from one setpoint to
others, or to indicate events to the setpoints from the external system.
Using Interval Timers
The SA300 has 16 interval timers that are commonly used for periodic recording of
interval data at the time of the fault or in the presence of other events detected by
setpoints. Some of the timers are factory preset for use with the Power Quality and
Fault recorders, and others can be programmed to generate periodic events at user-
defined intervals (see
Using Periodic Timers ).
Interval timers are not synchronized with the clock. When you run a timer, it
generates a pulsed timer event that can trigger a setpoint if you have put the timer
into a list of the setpoint triggers. When the setpoint event is asserted, the timer is
restarted, and then generates the next timer event when the timer interval expires.
If you want to record interval data at predefined intervals without linking to other
events, just select a timer as a setpoint trigger and specify in the setpoint actions list
a data log file you want to use for recording. If you want the periodic data to be
recorded in presence of a specific event, select triggers that identify your event, and
then add the timer at the end of the trigger list using the AND operator.
Using Time Triggers
If you want the setpoint actions to be synchronized with the clock, for example, to
provide synchronous recording interval data each 15 minutes or each hour, or to
output time pulses through relay contacts, use the time triggers that generate static
events synchronized to the device clock.
You can exercise the default setting for Setpoint #1 in your device as an example of
using time triggers. The setpoint is pre-programmed for data profiling at 15-minute
intervals using data logs #1 and #2.
Using the Voltage Disturbance Trigger
The voltage disturbance trigger (found under the VOLT DISTURB name in the
SPECIAL INPUTS trigger group) detects all types of the voltage waveshape faults on
any phase caused by fast transient voltages. You can use it to record disturbances if
you want to do this differently from the way the Power Quality recorder does it.
The operate threshold for the voltage disturbance trigger defines the maximum
allowable voltage deviation from a steady-state level above which the device declares
a waveshape fault. By default, it is specified as a percent of the nominal voltage. If
you wish to use volts units instead, you can select the desired voltage disturbance