SATEC PM180 Operation Manual User Manual
Page 80
Chapter 7 Programming the PM180
Using Control Setpoints
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PM180 Substation Automation Unit
Fault recorders, and others can be programmed to generate periodic events at user-
defined intervals (see
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 units from the Preferences tab in the Tools/Customize dialog (see
The trigger does not respond to slow voltage variations whenever the voltage rise
above or drop below the specified threshold takes longer than 1 cycle time.
Delaying Setpoint Operations
Two optional delays can be added to each setpoint to extend monitoring setpoint
triggers for a longer time before making a decision on whether the expected event
occurred or not. When a delay is specified, the logical controller changes the setpoint
status only if all conditions are asserted for a period at least as long as the delay
time.
Although a delay can be specified with a 1-ms resolution, the actual value is aligned
at a lower 1/2-cycle time boundary.
Note that you cannot use delays with pulsed events since they are cleared
immediately and do not longer exist on the next setpoint scan.
Using Setpoint Events and Actions
When a setpoint status changes, i.e., a setpoint event is either asserted or de-
asserted, the following happens in your device:
1. The new setpoint status is logged to the setpoint status register
that can be monitored from the SCADA system or from a
programmable controller in order to give an indication on the
expected event.
2. The operated setpoint status is latched to the setpoint alarm latch
register, which is remotely accessible. The register holds the last
setpoint alarm status until it is explicitly cleared.
3. Up to four programmable actions can be performed in sequence
on setpoint status transition when a setpoint event is asserted.