Cosel PJA600F-24 Switching Power Supply

The Cosel PJA600F-24 is a high-efficiency AC-DC switching power supply delivering 600W of regulated DC power. With a single 24V output rated at 25A, this unit is designed for industrial automation, test and measurement equipment, and telecommunications systems. The PJA600F-24 features universal AC input, active power factor correction, and a fan-cooled chassis-mount design.

Input Specifications

The power supply accepts a universal AC input voltage range of 85V to 264V AC, accommodating both 100-120V and 200-240V mains systems worldwide. Frequency range is 47-63 Hz, and the AC input current ranges from 3.2A at 230V AC to 7.5A at 100V AC. Power factor is corrected to 0.98 typical at 100V AC full load. Inrush current limiting protects against high startup surges, and the unit includes a built-in harmonic attenuator for compliance with IEC 61000-3-2 standards. Input-to-output isolation is rated at 3,000V AC.

Output Specifications

DC output voltage is factory-set at 24V with adjustment range typically from 21.6V to 26.4V via an onboard potentiometer. Output current rating is 25A continuous, delivering 600 watts of total output power. Line regulation is ±96 mV, while load regulation is ±150 mV. Output ripple is typically 180 mVp-p at full load. Overvoltage protection is set between 27.6V and 33.6V, and overcurrent protection is automatic with hiccup recovery. Hold-up time is typically 20 ms at 100V AC full load.

Efficiency and Thermal Performance

The PJA600F-24 achieves up to 88% efficiency at full load, minimizing heat generation and reducing power consumption. The unit is forced-air cooled by an internal fan that automatically adjusts speed based on load and temperature. Operating temperature range is -20°C to +70°C, with derating required at higher temperatures per the user manual specifications. The wide temperature capability allows deployment in both cold start-up environments and high-heat industrial bays. The supply operates at a switching frequency of 60-220 kHz.

Mechanical Design

The power supply is housed in a low-profile metal chassis measuring 120mm width, 61mm height (2U form factor), and 215mm depth, with a total weight of 2.0 kg. This compact design allows mounting in 2U rack enclosures. The chassis includes integral flanges for screw mounting. Input and output connections are made via screw terminal blocks or optional header connectors, with terminals rated for 10-16 AWG wire. A low-profile design reduces required panel space, and optional vertical terminal block or header connector configurations are available.

Protection and Safety Features

Comprehensive protection circuits include overcurrent protection that shuts down the output at specified thresholds, overvoltage protection that latches at approximately 27.6-33.6V, over-temperature protection that reduces output during excessive internal temperatures, and input surge suppression for industrial power line disturbances. The unit meets safety standards including UL 60950-1, C-UL, and TÜV EN 60950-1, and complies with RoHS environmental requirements. EMI filters meet FCC Class A and EN 55022 Class A standards.

Reliability and Longevity

The PJA600F-24 incorporates long-life electrolytic capacitors and a fan that is designed for extended operation. Mean time between failures (MTBF) is rated for long-term industrial use. The switching topology uses proven components with conservative derating practices to ensure reliability in continuous operation. No load power consumption is typically 1.5W at 240V AC input, contributing to low standby power usage.

Applications

This power supply is suitable for industrial control systems, programmable logic controllers (PLCs), robotic systems, LED lighting, test and measurement instrumentation, and telecommunications infrastructure. The combination of high output power and compact dimensions makes it ideal for applications requiring 24V at up to 25A with universal input compatibility.

Conclusion

The Cosel PJA600F-24 provides 600 watts of regulated 24V DC power in a compact 2U chassis, with universal input, high efficiency, comprehensive protections, and wide temperature operation. Its reliability and performance make it a solid choice for industrial power applications requiring sustained 25A output capability.