SATEC PM175 Manual - Manual (Page 79)

‎Chapter 4 PAS Application Software General Meter Setup
Series PM175 Powermeters 79
Option Range Description
Delays
Operate delay 0.1-999.9 sec The time delay before operation when the operate
conditions are fulfilled
Release delay 0.1-999.9 sec The time delay before release when the release
conditions are fulfilled
Setpoint #1 is factory preset to provide standard periodic data
logs on a 15-minute time basis. It is linked to the device clock
and runs data logs #1 and #2 at 15-minute boundaries of an
hour.
Using Logical Expressions
Logical operators OR/AND are treated in a simplified manner.
They have no specific priority or precedence rules.
Any trigger condition bound to the logical expression by the
OR operator and evaluated as “true” will override any
preceding condition evaluated as “false”. Similarly, any trigger
condition evaluated as “false” and bound by the AND operator
will override any condition evaluated before it as “true”.
To avoid confusion, it is recommended not to alternate
different logical operators in one expression. Instead, bring all
conditions that use the same logical operator together at one
side of the expression, and the others - at the opposite side.
To explicitly override all other conditions with the critical
trigger, put it at the end of the expression using the OR
operator if you want the setpoint to be operated anyway when
the trigger condition is asserted, and with the AND operator, if
the setpoint should not be operated while the critical trigger is
not asserted.
Using Numeric Triggers
For numeric (analog) triggers, a setpoint allows you to specify
two thresholds for each trigger to provide hysteresis (dead
band) for setpoint operations. The Operate Limit defines the
operating threshold, and the second Release Limit defines the
release threshold for the trigger. The trigger thresholds are
specified in primary units.
If you do not want to use hysteresis for the trigger, set the
Release Limit to the same as the Operate Limit.
Using Binary Triggers
Binary (digital) triggers, like digital inputs, relays, or internal
static and pulsed events, are tested for ON (closed/set) or
OFF (open/cleared) status.
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 event
flags.
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.