S&A T-503 Chiller Temperature Controller – 24VDC

LASER PARTS | WATER COOLING & CHILLERS

S&A T-503 Chiller Temperature Controller – 24VDC

The S&A T-503 is a digital temperature controller designed for compatible refrigerated water chillers used with CO2 laser engraving and cutting machines. It monitors coolant and ambient temperatures and controls the chiller's refrigeration components to maintain the required water temperature.

Manufactured by Guangzhou Teyu Electromechanical Co., Ltd., this controller features a digital temperature display, adjustable operating modes, built-in alarm functions, and a 24V DC power requirement.

It is a replacement option for compatible CW-series refrigerated chillers originally equipped with a matching T-503 temperature controller.

Important: The supplied controller is marked T-503 and features the nine-terminal wiring arrangement shown in the product photographs. Compare the model number and rear wiring diagram with your existing controller before ordering.

Key Features

• Digital Temperature Monitoring: Displays the circulating coolant temperature with 0.1°C resolution.
• Intelligent Temperature Control: Automatically adjusts the target coolant temperature in response to ambient temperature changes.
• Constant-Temperature Mode: Maintains a user-selected water-temperature setting within the controller's operating parameters.
• Two Temperature Sensor Inputs: Supports water-temperature and ambient-temperature NTC sensors.
• Refrigeration Control: Provides relay outputs for compatible compressor and solenoid-valve circuits.
• Temperature Alarms: Supports high and low coolant-temperature warnings and high ambient-temperature warnings.
• Sensor Fault Detection: Provides fault indications for water-temperature and ambient-temperature sensor problems.
• Audible Alerts: Built-in alarm buzzer and display indicators help identify operating problems.
• Adjustable Parameters: Allows configuration of temperature settings, cooling differential, control mode, and alarm limits.
• Panel-Mount Design: Compact controller with retaining clips for installation in a compatible chiller control panel.

Product Specifications

Product Type	Digital Chiller Temperature Controller
Manufacturer	S&A / Guangzhou Teyu
Model	T-503
Operating Voltage	24V DC
Voltage Tolerance	-20% to +10%
Rated Power Consumption	Less Than 3W
Panel Mounting Cutout	71 × 29 mm
Temperature Display	3-Digit Digital Display
Display Resolution	0.1°C
Sensor Inputs	2 NTC Temperature Sensors
Sensor Specification	10kΩ at 25°C
Compressor Relay Rating	16A
Solenoid Valve Relay Rating	10A
Temperature Control Modes	Intelligent / Constant Temperature
Front Panel Controls	Up, Down, SET, RST
Rear Connections	9 Screw Terminals
Application	Compatible Refrigerated Laser Water Chillers
Rabbit Laser USA SKU	272

Temperature Control Modes

Intelligent Temperature Mode

In intelligent mode, the T-503 adjusts its coolant temperature target according to changes in the surrounding air temperature. This mode is useful for laser cooling applications where maintaining a suitable relationship between coolant and ambient temperatures can help reduce condensation risk.

Constant-Temperature Mode

In constant-temperature mode, the controller regulates cooling around a fixed temperature setting selected by the operator. The compressor and solenoid-valve outputs operate according to the controller's programmed parameters and refrigeration requirements.

Both modes require a correctly functioning chiller and properly connected temperature sensors.

Digital Controls & Display

The front panel provides a digital temperature display, operating-status indicators, and four control functions.

• Up: Increases values and navigates adjustable settings.
• Down: Decreases values, navigates settings, and can display ambient temperature during normal operation.
• SET: Opens or navigates temperature-control and parameter settings.
• RST: Confirms or saves settings and returns the controller to its normal temperature display, according to the selected menu.

Operating-status indicators identify the active temperature-control mode, refrigeration status, and parameter-setting operation.

Alarm & Protection Functions

The T-503 includes built-in temperature monitoring and fault indications. When an alarm condition occurs, the controller displays an error code and provides an audible warning.

E1	High Ambient Temperature
E2	High Water Temperature
E3	Low Water Temperature
E4	Ambient Temperature Sensor Fault
E5	Water Temperature Sensor Fault

Pressing a control button during an alarm can silence the audible warning. The alarm indication remains until the underlying condition is resolved.

Important: Chiller flow alarms and external protection functions depend on the complete chiller configuration. The temperature controller does not replace the machine's water-flow protection system.

Electrical Connections

The T-503 controller uses a nine-terminal arrangement for refrigeration outputs, DC operating power, and temperature-sensor connections.

The rear identification label provides the terminal layout and connection diagram for this specific controller.

Controller power: 24V DC. The controller also features relay outputs used to switch external refrigeration circuits. The external compressor and solenoid-valve circuits may operate at different voltages from the controller's DC power supply.

Important: Always follow the wiring diagram printed on the replacement controller and verify it against the original installation. Controllers with similar front panels may have different terminal arrangements.

Chiller Compatibility

This controller is intended for refrigerated water chillers originally equipped with a compatible S&A T-503 controller. Applications may include selected CW-5000 and CW-5200 series chillers used with CO2 laser machines.

Before ordering, verify:

• Original controller model number
• 24V DC operating power
• Nine-terminal rear connection arrangement
• Panel mounting cutout dimensions
• Compressor and solenoid-valve circuit requirements
• Temperature sensor type and resistance
• Chiller manufacturer and production configuration

Compatibility Notice: T-503, T-503A, T-504, and newer chiller controller versions should not automatically be considered interchangeable. Confirm the exact terminal configuration and electrical requirements before replacing an existing controller.

Installation & Safety

• Disconnect the chiller completely from electrical power before servicing.
• Photograph and label every electrical connection before removing the original controller.
• Verify the replacement controller's voltage requirements, terminal arrangement, and relay ratings.
• Confirm compatibility with the existing water and ambient temperature sensors.
• Install the controller securely in the appropriate panel opening using its mounting clips.
• Follow the wiring diagram printed on the controller housing.
• Use a qualified service technician when working with compressor and refrigeration electrical circuits.
• Restore power only after all wiring and electrical connections have been checked.
• Verify temperature readings, refrigeration control, and proper alarm operation before returning the chiller to service.

Safety Note: Incorrect wiring can damage the temperature controller, compressor, solenoid valve, or connected equipment. Never bypass the chiller's protection circuits or operate the laser without verified cooling-water circulation.