SATEC PM174 Manual - Manual (Page 83)

Chapter 4 PAS
Application Software General Meter Setup
Series PM174 Powermeters 83
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
The PM174 provides 8 common binary flags, called event
flags, which can be individually set, cleared and tested through
setpoints and via communications.
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 externally trigger setpoint actions from the
SCADA system or from a PLC through communications.
Using Interval Timers
The PM174 provides four 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 a setpoint.
The timers 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 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 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 a data log file you want to use for
recording, in the setpoint actions list. If you want the periodic
data to be recorded in presence of a specific event, select
triggers that will 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.
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 will change the
setpoint status only if all conditions are asserted for a period at
least as long as the delay time.
Note that you cannot use delays with pulsed events since they
are cleared immediately and will no longer exist on the next
setpoint scan.