Compact 1U Rack Power Supplies for Redundant Industrial Systems

TDK Corporation has released a 1U rack-mount industrial power supply system delivering up to 3.5 kW per module, addressing the demand for compact, redundant power solutions in automation, test, and communications infrastructure.

High-density power for industrial and infrastructure use
TDK Corporation has announced the HFE3500 series from its power supply division, expanding its rack-mount portfolio with a system optimized for high power density and redundancy. Each 1U, 19-inch rack can house up to four power modules, providing a combined output of up to 13.3 kW. Multiple racks can be connected in parallel, enabling system-level scaling to 12 modules and supporting centralized bulk power distribution architectures.

The design targets applications such as factory automation, automatic test equipment (ATE), additive manufacturing systems, industrial printing platforms, RF transmission, base stations, and server infrastructure, where continuous operation and serviceability are critical.

Redundancy and hot-swap architecture
Each HFE3500 module is rated at 3,504 W when operated above 180 Vac input. Integrated ORing MOSFETs and active current-sharing circuitry enable hot-swap capability and N+1 redundant configurations without external isolation components. This approach reduces system complexity while allowing power modules to be replaced during operation, a common requirement in high-availability industrial systems.

The rack architecture supports parallel operation across up to three racks, maintaining load balance through the internal current-share function. This enables designers to build scalable power systems that can grow with increased load requirements while maintaining redundancy.

Electrical characteristics and control interfaces
The series is available with nominal 24 V and 48 V DC outputs, adjustable from 24.0 to 27.6 V and 48.0 to 55.2 V respectively. These voltage ranges align with common industrial control, motion, and telecom power buses.

An isolated PMBus™ (I²C) interface is included as standard, enabling digital monitoring and control within a digital supply chain environment. Parameters such as output voltage adjustment, remote on/off control, AC fail, and DC good status can be monitored or managed at system level. Auxiliary outputs of either 5 V or 12 V are provided to support control electronics.

The universal AC input range spans 85 to 264 Vac. Below 170 Vac, output power is derated to 2,016 W, allowing predictable operation under reduced input conditions. An option for dual AC input fuses supports installation in systems requiring additional input protection.

Mechanical design and efficiency
Each power module measures 107 × 40.1 × 330 mm, while the fully populated rack measures 444.5 × 43.7 × 428 mm, fitting within standard 1U enclosures. Cooling is provided by dual internal variable-speed fans, balancing thermal performance with acoustic considerations in equipment rooms.

Efficiency reaches up to 94% at 230 Vac input and 92% at 115 Vac, reducing thermal losses and easing cooling requirements in densely populated racks. High efficiency is particularly relevant in continuous-duty environments such as servers and RF transmission systems, where cumulative energy losses directly affect operating costs.

Compliance and isolation ratings
The HFE3500 series is certified to IEC, UL, CSA, and EN 62368-1 as well as EN/UL 61010-1, supporting use in both information technology and industrial measurement environments. CE and UKCA markings cover Low Voltage, EMC, and RoHS directives.

Conducted and radiated EMI compliance meets EN55011 and EN55032 Class A and B limits, along with FCC Part 15 and VCCI requirements, facilitating integration into mixed industrial and commercial installations. Isolation ratings are specified at 3 kVac input-to-output, 2 kVac input-to-ground, and 500 Vdc output-to-ground, supporting safe operation in grounded and floating system designs.

Positioning within industrial power systems
With a five-year warranty and support from TDK-Lambda Corporation, the HFE3500 platform is positioned for long-life industrial deployments. Its combination of power density, digital monitoring, and hot-swap redundancy addresses system designers’ requirements for modular, serviceable power infrastructures in modern automated and communications environments.

www.tdk.com