Setting up a standard Analog Output
A standard analog output provides an analog signal to control your application based on a fixed setpoint sensor (Sn-1,
Sn-2, or Sn-3).
Analog outputs provide an auto-selecting analog signal that is proportional to the sensed input condition. The System
450 analog output senses the impedance of the controlled equipment’s analog input circuit and automatically delivers
either a 0–10 VDC or 4–20 mA signal to the controlled equipment.
The control action between the input signal and the output signal can be set up four different ways, depending on the
values selected for the Setpoint (SP), End Point (EP), Percent Output Signal Strength at Setpoint (OSP), and Percent
Output Signal Strength at End Point (OEP). The LCD displays different Control Ramp icons for the four control actions.
The following figure shows an example of the analog output setup values and the resulting output signal in a typical
space heating application (SP > EP and OSP < OEP). The following table shows the four Control Ramp icons and describes
their corresponding control actions and the setup value relationships required to configure the four control actions.
Figure 44: Control Ramp example for a typical heating application (SP > EP and OSP < OEP)
Table 5: System 450 Control Ramps, Analog Output control actions, and system setup value relationships
Control ramp
displayed
Control action
Set the Analog Output value relationships for the desired
control action and corresponding control ramp
SP < EP
OSP < OEP
SP > EP
OSP < OEP
SP > EP
OSP > OEP
System 450 Series Reset Control Modules with Real-Time Clock and Relay Output Installation Guide
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