Product Overview

System 450™ Series Modular Controls Product Bulletin 5
Stand-Alone Multipurpose Controller
The versatile System 450 control module can also be
easily configured out-of-the-box as a stand-alone
control, which can provide SPDT control or proportional
analog signal control (depending on the model) for a
wide range of HVACR and commercial/industrial
applications.
With a C450CxN-x control module and the available
sensors and transducers (see Table 3 through Table 9),
almost any temperature, pressure, or humidity control
you may encounter in the field can be quickly replaced.
Control module models are available with either one or
two relay outputs or one or two analog outputs. See
Ordering Information
and Technical Specifications for
more information on System 450 control modules and
specifications.
Expansion Modules and Outputs
System 450 expansion modules (Figure 3) allow you to
increase the number of outputs in your control system
to meet your application requirements (Figure 11
through Figure 13). System 450 relay expansion
modules have either one or two SPDT relay outputs.
System 450 analog expansion modules have either
one or two analog outputs (0–10 VDC or 4–20 mA).
Relay Outputs
System 450 relay outputs provide SPDT control to your
system equipment based on the reference sensors set
up in your control system. Multiple relay outputs can
provide staged SPDT control. Single relay outputs can
also activate alarms for your controlled systems.
Each relay output is an SPDT set of line-voltage
contacts with Normally Open (LNO), Normally Closed
(LNC), and Common (LC) wiring terminals (Figure 11
through Figure 13). See Technical Specifications
for
more information, including electrical ratings.
SPDT relay outputs are featured on two control module
models and two expansion module models. See
Ordering Information
for model information.
Analog Outputs
System 450 analog outputs generate proportional
signals to your system equipment. Each analog output
generates either a 0–10 VDC or 4–20 mA signal. The
signal type is self-selecting; the output automatically
detects the input signal target on the controlled
equipment and generates the appropriate type of
analog output signal to the equipment’s input.
Analog outputs are featured on two control module
models and two expansion module models. See
Ordering Information
for model information.
Selectable Proportional Control Action
A System 450 control system allows you to set up the
control action of each analog output in your control
system to respond to load changes in one of four
different ways:
• Proportional output lowest at setpoint, with output
increasing as sensor value increases
• Proportional output lowest at setpoint, with output
increasing as sensor value decreases
• Proportional output highest at setpoint, with output
decreasing as sensor value decreases
• Proportional output highest at setpoint, with output
decreasing as sensor value increases
An analog output’s control action is automatically
determined by the setup values you select for the
Setpoint, End Point, % Output at Setpoint, and
% Output at Endpoint values when you set up the
output in the UI.
An indicator (control ramp) appears on the output
status screen for each analog output to represent the
analog output’s control action.
For a more detailed explanation of the control actions
and control ramps, refer to the System 450 Series
Modular Controls Technical Bulletin (LIT-12011459).
Figure 3: System 450 Expansion Module With
Two Relay Outputs