System 450™ Series Modular Control Systems with Standard Control Modules Technical Bulletin
15
Relay On and Off Duration Control
The System 450 provides four time duration control parameters that can be applied to the relay output On or Off
times generated by an input sensor or a binary input. Each of the four On or Off duration control parameters can be
set up for 0 to 300 seconds (5 minutes) in 1-second intervals.
The four time duration control parameters are as follows:
• On Delay: (ONd) Delays the time that a relay output goes to the On state after reaching the On condition. See
the third graph in Figure 5.
• Off Delay: (OFFd) Delays the time that a relay output goes to the Off state after reaching the Off condition. See
the bottom graph in Figure 5.
• Minimum On Time: (ONT) Maintains the relay in the On state for the selected minimum time after reaching the
On condition and overrides any sensor input that would normally switch the relay off during the Minimum On
Time interval. See the third graph in Figure 6.
• Minimum Off Time: (OFFT) Maintains the relay in the Off state for the selected minimum time after reaching
the Off condition and overrides any sensor input that would normally switch the relay on during the Minimum
Off Time interval. See the bottom graph in Figure 6.
The top two graphs in Figure 5 and Figure 6 show an example of a binary input opening and closing (top graph in
each figure) and the resulting behavior of the referenced relay output with no On/Off duration parameter applied to
the relay output (second graph in each figure).
The second graph in each figure can also represent a typical example of a relay output responding to the On and
Off values for any System 450 compatible sensor.
The third and the bottom graphs in Figure 5 and Figure 6 show the behavior of the output relay when the On and
Off Delay parameters are applied (Figure 5) and when the Minimum On and Minimum Off parameters are applied
(Figure 6) to the output.
The bottom two graphs in Figure 5 show an example of the relay output behavior when the On or Off Delay
parameter is applied to the relay output (regardless of whether the relay output references a binary input or another
compatible sensor).
To Next Page
Loading...
Need help?
General
