Description - PENN Controls - LIT-1900900 - C450CEN - System 450 Multi-Purpose Modular Control System - C450CEN Communications Control Module for Ethernet

Controlling Head Pressure on a Two-Circuit Condenser with High Input Signal Select Application Note
Product
Controls > Multi-Purpose Modular Controls > C450CEN Communications Control Module for Ethernet
Document type
Application Note
Document number
LIT-1900900
Revision date
2020-04-15
Important: Use the System 450™ control module only as an operating control. Where failure or malfunction of the System 450 control module could lead to personal injury or property damage to the controlled equipment or other property, additional precautions must be designed into the control system. Incorporate and maintain other devices, such as supervisory or alarm systems or safety or limit controls, intended to warn of or protect against failure or malfunction of the System 450 control module.

Refer to the System 450 Series Modular Control Systems with Communications Control Modules (LIT-12011826), the System 450 Series Modular Controls Product Bulletin (LIT-12011458), and the installation instructions for product specifications, detailed installation procedures, and important product safety information.

When a cooling system has a two-circuit condenser with a single cooling fan, it is necessary to control the fan based on the condenser circuit with the highest pressure. The C450CEN-x Control Module is capable of performing this function using the high input signal select feature.

You must use identical sensors connected to Sn1 and Sn2 to enable the high input signal select feature (HI-2). Install two identical P499 Electronic Pressure Transducers on the high side of each circuit, and wire them as shown in the wiring diagram. The liquid line on the outlet side of the condensers is the recommended mounting location. The C450CEN-x Control Module can perform high input signal select using up to three inputs, but this example only uses two inputs. Use the C450SPN-x Expansion Module in the place of the C450SQN-x Expansion Module if you do not need a spare output.

Figure 1. C450CEN-x Control Module Controlling Head Pressure on a Multi-Circuit Condenser with a Single Fan Using High Input Signal Select

The High Input Signal Select 2 (HI-2) functional sensor is selected in this application example. When the sensors connected to Sn1 and Sn2 are the same sensor types, the HI-2 sensor is enabled for selection. When you select the HI-2 sensor for an output, the output is controlled by the sensor (Sn-1 or Sn-2) that is sensing the higher value of the two inputs.

Figure 2. Status and UI Setup Screens for the C450CEN-x Control Module Controlling Head Pressure on a Multi-Circuit Condenser with a Single Fan Using High Output Signal Select Example

The following screen captures show the web user interface on the C450CEN-x Control Module.

Note: The System 450 web UI screens and values shown are for the application example illustrated on the previous page. The screens and values for your application may vary depending the sensors connected and the desired setpoints.
Figure 3. System Configuration Screen

Figure 4. Sensor Configuration Screen

Figure 5. Output Configuration Screen for OUTA1

Note: Refer to the System 450 Series Control Modules with Communications Technical Bulletin (LIT-12011826) for information on setting up the network parameters for your Ethernet network.