Emerson Site Supervisor, User Manual

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5-4
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Site Supervisor Controller User Guide 2.0 026-1800 Rev 3 02-AUG-2016
• Minimum value
• Maximum value
• First - first input value that is not NONE
• Mix of first two inputs (using mix ratio property)
• Span - difference between the highest and lowest
input values (multiple inputs)
• Select - single value chosen by the input select (if
input select is 5, use in5)
• Sum - sum all inputs
• (in1 + in2) + in3
• (in1 - in2) - in3
• (in1 * in2) * in3
• (in1 + in2) / in3
• (in1 * in2) + in3
• (in1 - in2) * in3F
• |in1 - in2| / in3
• |in1 - in2| * in3
• sqr(|in1 - in2|) * in3
The combined values can be filtered. The filter’s
primary function is to slow the rate of change of the
combined input. The difference between the current input
value and the input's value x seconds ago, where x =
Factor Time, is multiplied by the filter ratio to produce the
filter output.
The filtered output is run through a CutIn / CutOut calg
that trips a digital output (Command Out) based on the
CutIn / CutOut setpoints.
There is also a counter on the Command Out that
provides a running count that increase every time the
Command Out cycles to ON and a digital Counter Trip
Output that is ON when the Counter value is greater than
the Counter's trip point. The user enters the initial value
and the count increases by the Count Inc value. The Count
output value is reset by sending a signal to the Reset Count
input. The Count Reset Type parameter specifies whether
the Count is reset based on the logic level, the rising edge
or the falling edge. The counter increase based on the
digital output after the bypass block.
The PRI DEMAND SHED and SEC DEMAND SHED
inputs provide a way to have the cell shut down in demand
shed situations. If the PRI DEMAND SHED is ON, the
Cut In/Cut Out setpoints is bumped by the amount set in
the Pri Demand Bump parameter. Likewise, for the SEC
DEMAND SHED except the primary demand shed has
priority if they are both ON. The Stpt Bump Rst Int
indicates the amount of time over which the setpoint is
ramped back to normal.
5.2.2 Control Alarming
There is a high and low limit alarm and notice for the
inputs after they are combined and filtered. The user sets
occupied and unoccupied, high and low setpoints. If the
combined/filtered value exceeds either the notice or alarm
setpoints, a notice or alarm is generated. If the Alarm
Disable or Notice Disable input is high, the Alarm or
Notice output, respectively, is forced to OFF. There are
Notice and Alarm digital outputs that the user can connect
to. In addition, the alarm and notice is automatically sent
to AdvisoryServices.