Allen-Bradley 1404-M4, User Manual

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Publication 1404-UM001D-EN-E - October 2004
5-2 Setpoint Programming and Operation
You may read setpoint output flags in Table A.3 Discrete Data and
Table A.2 Remote I/O, DeviceNet, EtherNet/IP and ControlNet I/O
Messaging. You may read only the first 8 setpoint output flags in the
discrete input table with optional Remote I/O communications.
Setpoints evaluate data based on six different conditions: over
forward, over reverse, under forward, under reverse, equal, and not
equal. Over and under setpoint evaluation conditions may only be
used with analog values such as voltages, currents, power, etc.
Reverse setpoints are typically used to monitor power and energy
when on-site generation is present. Equal and not equal evaluation
conditions are for use with discrete conditions such as phase rotation,
status inputs and transient detection.
Over Forward Setpoint
An over forward setpoint activates when the magnitude of the
parameter being monitored (defined by the Setpoint Type ) increases
beyond the Setpoint High Limit and remains over the limit for a time
greater than the Setpoint Action Delay . The setpoint releases when the
magnitude of the parameter being monitored decreases below the
Setpoint Low Limit and stays below the limit for a time greater than the
Setpoint Release Delay .
Figure 5.1 Over Forward Setpoint Operation
TIP
You should assign each setpoint a unique action
type. If more than one setpoint are assigned an
action type, unpredictable output action may result.
Parameter Value
Setpoint High Limit
Setpoint Low Limit
Setpoint Activated
<Setpoint Action Delay
≥
Setpoint Action Delay <Setpoint
Release Delay
≥
Setpoint
Release Delay
Time (s)
0
Maximum Excursion