System 450™ Series Modular Control Systems with Standard Control Modules Technical Bulletin
27
When any one of the connected sensors (Sn-1, Sn-2, or Sn-3) or associated sensor
wiring fails, all of the outputs that reference the failed sensor, either directly or
through a functional sensor, go into the outputs’ selected sensor failure modes and
continue to operate in the sensor failure modes until the sensor or sensor wire
failure is corrected.
You can select either On or OFF for an output’s Sensor Failure Mode. Depending
on the type of output (relay or analog), the On and OFF Sensor Failure Modes are
defined as follows:
•
Relay output SNF ON = Relay On. (See
information regarding a relay output’s on state.)
•
Relay output SNF OFF = Relay Off. (See
information regarding a relay output’s off state.)
•
Analog output SNF ON = Output Signal Strength at End Point (OEP). (See
on page 20 for more information regarding Output Signal at
End Point.)
•
Analog output SNF OFF = Output Signal Strength at Setpoint (OSP). (See
on page 20 for more information regarding Output Signal at
Setpoint.)
System 450 Standard Control System Examples
With System 450 control and expansion modules, you can build a wide variety of
cost-effective, custom control systems. Each of the following examples provide an
illustration of the module assembly, including wiring diagrams for system sensors
and outputs, and menu flow charts showing typical Main screens and System
Status screens, along with System Setup screens and example setup values.
Note:
The physical configurations, wiring, and setup values shown in the
following examples are meant to illustrate typical control system
applications, control features, and system setup values. Your control
applications may require different modules, module configurations,
sensors, wiring, and UI setup parameters and values.
Control Modules and User Interface
Module Assemblies, and Outputs
on page 13 for general information and
guidelines on System 450 modules and UI. See
for information and procedures on designing your control system, selecting
modules and sensors, mounting and wiring your control system, accessing and
navigating the System 450 UI, and setting up your control system in the UI.
Standard System 450 control systems use the C450CxN-x control modules along
with System 450 expansion modules. The following standard control system
examples illustrate on/off relay control, proportional analog control, multi-state
control, High Input Signal Selection, and/or Differential Control. See
