Phoenix STEP-PS/277AC/24DC/3.5 Power Supply
The Phoenix STEP-PS/277AC/24DC/3.5 Power Supply (Item No: 2904945 ) offers a 85 V AC ... 305 V AC input voltage range, > 88 % (for 277 V AC and nominal values) efficiency, 24 V DC ±1 % nominal output voltage, 3.5 A (-25 °C ... 55 °C) nominal output current. Manufactured by Phoenix under the Phoenix Power Supply category, this model belongs to the Phoenix STEP Series.
| Brand | Phoenix Contact |
| Product Type | Power Supply |
| Model Number | STEP-PS/277AC/24DC/3.5 |
Phoenix STEP-PS/277AC/24DC/3.5 Power Supply – Technical Specifications
| Specification | Value |
|---|---|
| Nominal input voltage range | 100 V AC ... 277 V AC |
| Input voltage range | 85 V AC ... 305 V AC |
| Inrush current | < 40 A (typical) |
| Efficiency | > 88 % (for 277 V AC and nominal values) |
| Nominal output voltage | 24 V DC ±1 % |
| Nominal output current (IN) | 3.5 A (-25 °C ... 55 °C) |
| Residual ripple | < 10 mVPP (20 MHz) |
| Power loss nominal load max. | 11.5 W |
| Insulation voltage input/output | 4 kV AC (type test) |
| Mounting type | DIN rail mounting |
| Degree of protection | IP20 |
| Ambient temperature (operation) | -25 °C ... 70 °C (> 55° C derating : 2.5%/K) |
| EMC requirements for noise emission | EN 61000-6-3 |
| EMC requirements for noise immunity | EN 61000-6-1 |
The Phoenix STEP Power Supply STEP-PS/277AC/24DC/3.5 (Item No: 2904945) is an 84-watt primary switched-mode power supply built to support modern industrial systems with precision and reliability. Operating within a wide input voltage range of 85 V AC to 305 V AC, this model is compatible with both standard and high-voltage supply networks. It delivers a nominal output voltage of 24 V DC ±1% and a robust output current of 3.5 A, making it ideal for powering PLCs, sensors, and control circuits. A high efficiency rating of over 88% at 277 V AC reduces thermal load and energy wastage, while residual ripple remains under 10 mVPP—a critical factor for sensitive electronics.
Engineered with an inrush current under 40 A and a power loss of just 11.5 W, it offers superior performance under full load. Safety features include a 4 kV AC insulation voltage between input and output, IP20-rated protection, and compliance with EMC standards EN 61000-6-1 and EN 61000-6-3 for noise immunity and low emission. The DIN rail mounting system ensures quick installation in compact industrial cabinets, and the unit functions efficiently across -25 °C to +70 °C, with a defined derating above 55 °C.
The STEP-PS/277AC/24DC/3.5 is designed for control panel builders, automation engineers, and maintenance professionals seeking a dependable power supply for mission-critical applications. From powering distributed I/O systems to acting as a steady voltage source for relays and HMI units, it plays a vital role in factory automation and process control. With its compact form factor, energy efficiency, and industrial-grade reliability, it simplifies system design while improving power distribution. Whether you are building new machines or retrofitting older setups, this 84 W model offers a versatile and future-ready solution.
To learn more or download datasheets, visit the official Phoenix Contact product page for STEP-PS/277AC/24DC/3.5. Brand: Phoenix Contact, Model: STEP-PS/277AC/24DC/3.5, Item No: 2904945. Secondary keywords: 24V DC DIN Rail PSU, 84W Step Power Supply, Phoenix STEP Series, Industrial Power Supply 24V 3.5A.
