©2025 Copeland LP.
026-1803 R13 Supervisor I&O User Guide 9 - 13
9.10 Digital Sensor Control
The Digital Sensor Control read the values from one or more
digital sensors, combine them using a series of logical
commands, and operate a digital output (such as a relay)
based on the result of the logical combination.
The Digital Sensor Control module performs three basic
functions:
• LOGICAL COMBINATION - up to four inputs may be
combined using standard logical combination methods
(such as AND, OR, XOR). The result is the command
output value, which can be used to operate a relay.
• BYPASS - The command output may be configured to be
bypassed to a fixed value by a switch or button press.
• ALARMING - Alarms and notices can be generated
based on the command value of all the digital inputs of
the cell, plus occupancy, and schedules.
9.10.1 Control Strategy
The Digital Output Module cell provides a mechanism for
combining multiple Digital Outputs into a single output that
can be used as an input to other cells.
The inputs can be combined as the following:
• AND - logical AND of inputs
• OR - logical OR of inputs
• XOR - logical XOR of inputs
• VOTE - result will be ON if the number of inputs
ON > number of inputs OFF
• FIRST - returns the logical value of the first good (non-
DV_NONE) input. There is also a First Good output which
shows the number 1-4 of the first good input.
The Digital Output Module allows for a user to specify two
different input combination strategies: a primary combination
type, and an alternate combination type. The module reads
the state of the Use Alternate Combination method input to
determine which combination method to use.
The combined value is then sent to a Schedule Interface
strategy. The Schedule Interface strategy allows the user to
modify the combined value based upon the occupied or
unoccupied state of the system. Two different combination
strategies may be specified by the user; a primary
combination strategy and an alternate combination strategy.
When the Use Alt Shed input is LOW, the primary
combination is used. When the Use Alt Shed input is HIGH,
the alternate combination strategy is used.
The output is then sent to a Min On/Min Off property that sets
its output based on the Min On/Min Off delay times.
The resulting output is passed to a One-Shot calculation for
applications that require a pulse rather than a logic level. The
output of the One-Shot can be a pulse of length Pulse Width
seconds that starts when the input to the One-Shot rises or
falls depending on the Timer Type selection.
The Proof Fail output will be active as a result of comparing
the final control value with the Proof input. If the input and
output do not match for a length of time equal to the Proof
Delay, the Proof Fail output will go to ON. It will stay ON for at
least Proof Latch Dur seconds. The user can select to use the
actual value from the Command output or the output from the
Min On/Min Off property. The proof will generate an alarm if
the Proof Alarm Type property is not set to Disabled.
There is also a counter on the Command Out that provides a
running count that increments 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
increments 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 increments based on the digital output after the
bypass block.
The PRI DEMAND SHED input provides a way to have the cell
shut down in demand shed situations. If the PRI DEMAND
SHED is ON, the output will be set to the logical OFF position
by using the bypass functionality. The Cmd When Off param
will set the proper off value for the output. The counter will not
increment when in demand shed regardless of the inputs.
9.10.2 Command Alarming
The command value will be used to determine the alarm
state. The command value is the combined value of all the
digital inputs of the cell, plus occupancy, and schedules.
When the command value changes to alarm condition, the
delay timer will start. If the state changes, the timer will stop
and no alarm will be issued. If the state stays for the duration
of the timer, an advisory will be issued. If a state change
occurs to the opposite state after the advisory has been
issued, it will be returned to normal.
If the advisory is reset, and the alarm/notice condition still
exists, the delay period will be honored. Advisories will return
to normal if the command value stays in the non-alarm/notice
condition for the duration of the clear delay. If the command
value changes back to the alarm condition, during the clear
timer, the advisory will not return to normal.
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