Atlas Copco D303‑DL‑BASIC Controller (D303DLBASIC)

The Atlas Copco D303‑DL‑BASIC, also referenced as D303DLBASIC, is a compact programmable logic controller (PLC) designed for simple automation and control tasks in industrial environments. This controller is part of Atlas Copco's D‑series family, offering a cost‑effective solution for standalone machine control, conveyor systems, and auxiliary equipment. Its small footprint, built‑in I/O, and easy‑to‑use programming environment make it accessible for both OEMs and end‑users who need reliable, basic control functionality.

Controller Hardware

The D303‑DL‑BASIC features a rugged plastic housing with a transparent cover for easy status viewing. It includes a set of integrated digital inputs and outputs, as well as communication ports for programming and interaction with operator panels. The unit is designed for DIN‑rail mounting, with spring‑clamp terminals for secure wiring. It operates on a 24 VDC supply and consumes minimal power.

Technical Specifications

• Supply Voltage: 24 VDC ±20%

• Digital Inputs: 6 (24 VDC, sink/source)

• Digital Outputs: 4 (relay, 2 A @ 250 VAC)

• Input Filter: 1 ms (defeatable)

• Output Protection: Short‑circuit and overload

• Communication: RS‑485 Modbus RTU, USB (programming)

• Programming Language: Ladder logic (IEC 61131‑3 compliant)

• Memory: 128 KB program, 32 KB data

• Real‑Time Clock: Yes (battery‑backed)

• Operating Temperature: -10 °C to +55 °C

• Protection: IP20

• Dimensions: 110 x 90 x 55 mm

Programming and Configuration

The controller is programmed using Atlas Copco’s D‑Studio software, which provides a user‑friendly ladder logic editor with online monitoring and debugging capabilities. Users can create simple control sequences, timers, counters, and arithmetic functions. The software includes a library of common function blocks for motor starting, alarm handling, and valve control. Programs can be uploaded, downloaded, and saved to the internal EEPROM for permanent storage.

Connectivity and Expansion

A built‑in RS‑485 port allows connection to external HMIs or SCADA systems via Modbus RTU. The USB port is used for programming and firmware updates. The controller can be expanded with additional I/O modules from the D‑series family if more points are needed.

Applications

Typical applications include: control of small conveyor belts, packaging machines, drying ovens, pump and fan sequencing, alarm annunciation, and simple machine safeguarding. It is also used in compressor accessory control, such as automatic condensate drains and filtration systems.

Reliability and Maintenance

The D303‑DL‑BASIC is built with industrial‑grade components and has a MTBF of over 80,000 hours. It has no internal moving parts and requires no routine maintenance except for periodic battery replacement for the RTC (every 5 years).

Safety

The controller includes a hardware watchdog that forces outputs to a safe state in case of processor fault. Emergency stop inputs can be wired directly to a safety relay, with the controller monitoring the status.

Benefits

This controller offers a low‑cost entry into automation with minimal learning curve. Its compact size allows installation in tight spaces, and its robust construction ensures long‑term reliability. The Modbus support enables easy integration with existing plant networks.

Conclusion

The Atlas Copco D303‑DL‑BASIC is a reliable, cost‑effective controller for straightforward automation needs, backed by Atlas Copco’s quality and support.