Bel Power Solutions - Railway Technology
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Bel Power Solutions

Melcher Brand, DC / DC and AC / DC Converters for Railway and Rugged Applications

Bel Power Solutions is a leading global manufacturer of power conversion and power management solutions, with a long history of providing leading-edge, innovative and reliable power technology. We are an industry leader in ruggedness, power density with ultra-high efficiency. MELCHER was acquired by Bel Power Solutions in 1998.

2390 Walsh Avenue,
Santa Clara,
United States of America

Bel Power Solutions is one of the largest power supply manufacturers in the world and has a long history of providing leading edge, innovative power solutions. Under the MELCHER brand, Bel provides the leading manufacturers in the railway and transportation industry worldwide with high performance, rugged DC / DC and AC / DC converters.

Bel Power Solutions in the railway industry

Bel Power Solutions provides leading manufacturers in the railway and transportation industry worldwide with high-performance, rugged DC / DC and AC / DC MELCHER™ brand converters.

With more than 40 years of design and manufacturing experience, MELCHER products are designed to meet the highest national and international standards for harsh environments, safety and electromagnetic compatibility and interference (EMC / EMI) as well as undergo rigorous and extensive engineering and design validation tests ( EVT / DVT), highly accelerated life tests (HALT) and highly accelerated stress screen (HASS) tests.

Our strict engineering guidelines ensure low component stress, thermal profiling and high phase margins for stability and dynamic response.

Melcher AC / DC and DC /DC products

There are literally hundreds of thousands of Bel Power’s MELCHER products installed around the globe, whether on rolling stock or trackside. Our MELCHER cassette DC / DC and AC / DC power converters designed for railway applications have successfully passed all tests and requirements according to the material fire safety of DC / DC and AC / DC converters according to EN 45545-1, EN 45545-2 (2013) for hazard levels HL1 to HL3.

The fire safety tests have been conducted at a certified lab. In addition the above the products also comply with national versions of fire and smoke standards, in particular DIN 5510-2 and NFF 16-101 (1988) classification I3 / F2.

Products features and benefits include:

  • Compliance with International and national standards (EN, UL, AREMA, RIA, NFF), in particular EN50155 and 50121
  • Fire safety according to EN 45545 for hazard levels HL1 to HL3
  • Ultra-wide DC input voltage, up to 10:1 ratio, suitable for all common battery input voltages worldwide
  • Extremely high efficiencies
  • Fully featured, full fault protection: transient, over-temperature, over / undervoltage, overcurrent
  • 3.3V to 96V output voltages with wide trim range
  • Series and parallel or fully redundant configurations
  • On / off control, current share and other options
  • Extended ambient operating temperature to -40°C or lower on request
  • Convection and conduction cooling with no derating up to 70°C
  • All PC boards dip-varnished for high mechanical durability and humidity withstand, without use of potting material
  • Shock and vibration resistance
  • Basic or reinforced insulation, test voltages up to 3k VAC
  • Multi platform approach for highest flexibility
  • All products are fully compliant with the Restriction of Hazardous Substances (RoHS) directive

LBC Series battery chargers

The LBC Series is a ruggedised battery charger consisting of two or three parallel independent AC-DC converters employing power factor correction (PFC) stages and insulated DC-DC stages to convert the three-phase input voltage 400 / 480 VAC (line to line) to a bus voltage suitable for 110V battery charging. The system includes a digital signal processor (DSP) for control and monitoring.

  • Input voltage range 400 / 480Vrms 3-phase
  • Output power up to 12kW
  • High power density with 13W/in3 per unit
  • 110VDC output is decoupled with a diode for redundant applications
  • Output voltage for 110V battery (adjustable 85VDC-137.5VDC)
  • Operating temperature -25°C to 55°C, without derating
  • Controller area network (CAN) bus / Ethernet interface
  • EN50155 and EN45545-compliant
  • For railway applications

Rugged 3U cassettes for 19in rack or chassis mount

The rugged MELCHER products offer the industry’s premier line of standard products for DC / DC and ACDC power conversion, including custom design capability for application specific power conversion solutions.

For more than 40 years Bel’s MELCHER lineup of DC / DC and AC / DC cassette-style power converters with extremely robust electrical and mechanical designs have demonstrated to provide consistent power to a diverse array of railway, signaling, communications, transportation and industrial infrastructure applications.

  • DC / DC converters with extremely wide input covering battery applications from 12V to 220V nominal
  • Universal AC input with identical form factors
  • Inrush current limitation
  • Reverse polarity protection
  • Up to 300W output power
  • High efficiency, up to 94.5% including input filter
  • Ultra-wide output voltage adjustment
  • Remote on / off control input
  • Current share, redundancy
  • Rugged aluminium extruded case, conformally coated assemblies
  • Self cooling, no derating over the specified temperature range
  • Compliance with EN50155, EN60571, EN50121-3-2,
  • UL / EN60950 and national deviations (AREMA, RIA, NFF)
  • Input / output overvoltage protection
  • All products are fully transient protected
  • No-load, overload and short-circuit protection
  • Thermal protection

Isolated PC-board mount DC-DC converters

Bel Power Solutions offers a wide range of PCB-mount DC-DC converters that are especially designed and manufactured for the railway and transportation markets.

  • Various wide DC input voltage ranges with or without isolation from 7VDC-160VDC, including platforms with 10:1 ratio
  • Output voltages from 3.3V-54V with trim ranges as wide as 0%-110% Vout nominal
  • Wide operating temperature ranges with startup at -40°C or below and no derating to 70°C
  • Dip-varnished circuits without potting material for maximum reliability
  • Isolated converters with magnetic feedback and I / O test voltages up to 3k VAC
  • Low output ripple and excellent dynamic response
  • Maximum flexibility for modular-type platforms instead of custom designs
  • High shock and vibration resistance
  • Input overvoltage and under voltage lockout protection
  • Current limit and short-circuit protection
  • Thermal protection
  • Output overvoltage protection (OVP)
  • Input transient protection

Non-isolated buck DC / DC converters

Bel Power Solutions offers a wide range of positive switching regulators designed as power supplies for electronic systems, where no input-to-output isolation is required. Their major advantages include a high level of efficiency, high reliability, low output ripple, and excellent dynamic response.

DIN rail AC / DC and DC / DC products

The Melcher LX / LW series of industrial / transportation DIN rail power supply units (PSU) are designed for rugged and harsh environments, where reliability is critical, featuring single or dual outputs and battery charging options.

RCM 150/300 Series

Bel Power Solutions RCM Series converters comprise durable power supplies for railway and transportation applications.

RCM 500/1000 Series

The RCM500 and RCM1000 Series of converters are features durable power supplies for railway and transportation use.

0RQB-C2Q12 Series

The Bel Power Solutions 0RQB-C2Q12x series features an isolated railway DC/DC converter that operates from a nominal 24 VDC source.

0RQB-30Y05L Series

The 0RQB-30Y05L series features an isolated DC/DC converter that delivers 30 W of output power from a range of inputs.

HP Series

The HP Series of compact DC-DC converters incorporates input and output filters, signalling, and protection features that are required for most railway applications.

DC-DC and AC-DC Converters

The RCM Series (Railway Chassis Mount) DC-DC converters are reliable power supplies for railway and transportation systems.

Stewart Connector Releases M12 A-Code Series Connectors

Bel group company Stewart Connector has released the M12 A-Code Series, targeting environments where rugged connectors are needed to power and communicate with equipment widely found in today’s manufacturing environments.

Bel Power Solutions Introduces LDD240-WU

A revolutionary DIN Rail DC-DC converter LDD240-WU has been introduced by Bel Power Solutions. It offers flexibility, compactness and a high level of reliability.

Bel Power Solutions Announces New SLDM Tunable Loop™ Non-Isolated DC-DC Converter

Bel Power Solutions, a Bel group company (NASDAQ: BELFA and BELFB) and premier global manufacturer of power management devices, announces the new SLDM Tunable Loop™ SLDM-06D1Ax and SLDM-12D1Ax modules, which are ultra-low profile, non-isolated DC-DC converters that deliver up to 6A and 12A with maximum flexibility of being mounted on the top side or bottom side of the host PCB.

Bel Power Solutions Introduces High-Power LBC Series Railway Battery Chargers Designed for Train Manufacturers

Bel Power Solutions, a Bel group company, (NASDAQ: BELFA and BELFB) and premier global manufacturer of power management devices, today introduced the LBC Series, a ruggedized battery charger consisting of two or three parallel independent AC-DC converter modules employing PFC stage and isolated DC-DC stage to convert the three-phase input voltage 400 / 480 VAC (line to line) to a bus voltage suitable for 110V battery charging for decentralised railway applications.

Bel Fuse Announces the Launch of Its New Website

Bel Fuse (NASDAQ:BELFA and NASDAQ:BELFB), a leading global manufacturer of products that power, protect and connect electronic circuits, is pleased to announce the launch of their new website at

Bel Power Solutions Introduced Compact, Ruggedised Melcher™ HP Series

Bel Power Solutions announces the release of its MELCHER™ HP Series DC-DC converter (4TE) with an input voltage range greater than 10:1. The converters deliver up to 192W with typical efficiency up to 93% over input and load range with no derating over the operating ambient temperature range of -40° to 70°C.