車両内および線路アプリケーション用DC/DCコンバータ

R-REF04-RIA12

• 入力電圧：9～160VDC
• 出力電力：8～240W
• CEおよび EN50155認証取得済み
• UL/IEC/ EN60950認証取得済み及びCE マーク済み
• UL部品承認済み
• 高効率：93%
• 温度範囲：-45℃～+97℃
• ケース：DIP24/SMD、1"×1"、2"×1"、1/4ブリック、1/2ブリック

RSPxxx-168シリーズは、最大385VDCという高いサージ電圧から鉄道用DC/DCコンバータを保護するために設計されたサージプロテクターモジュールです。出力電圧は3.3V、5V、12V、15Vに加えて±12V、±15Vを用意しています。制御端子のロジックは正と負が選択できます。効率は最大93%を達成し、通常は自然対流による冷却で十分ですが、必要に応じて放熱器付きパッケージも提供可能です。RECOM標準の3年保証が付帯しています。

Heat, frost, vibration, and mechanical shock can cause severe damage to electronic assemblies over time. DC/DC converters used in railway engineering are exposed to demanding operational conditions and must function reliably throughout their long service life. Consequently, design engineers prioritize converters that are specially certified and ruggedized to withstand these extreme conditions.

EN 50155 (Railway Applications – Electronic Equipment Used on Rolling Stock) specifies strict requirements for electronic equipment deployed in railway engineering. This standard applies directly to DC/DC converters, which serve as critical power supplies for drive assemblies, control electronics, and onboard systems across all rail vehicles, including locomotives, passenger coaches, light rail, and freight trains.

EN 50155 defines minimum performance criteria for input voltage ranges, electrical isolation, operating temperatures, shock and vibration, humidity, electromagnetic compatibility (EMC), and overall equipment life. Because rolling stock electronics are expected to operate for up to 20 years, environmental testing is exceptionally thorough. Beyond standard thermal testing, modules undergo thermal cycling, dry heat, and damp heat evaluations—requirements typically met using fully potted or hermetically sealed converters.

Ambient temperatures in rail applications can exceed +60°C in summer and drop below -30°C in winter. Furthermore, operating converters in moving vehicles exposes them to severe thermal shifts alongside continuous vibration. The latest EN 50155 standard outlines six distinct operating temperature classes and mandates rigorous testing for start-up performance under extended temperature limits.

EN 50155 sets baseline environmental guidelines requiring equipment to withstand an average relative humidity of 75%, followed by 30 consecutive days at 95% relative humidity. To endure these conditions without corrosion or short circuits, converter assemblies utilize watertight enclosures or protective conformal coatings.

Railway electronics must operate faultlessly in intense electromagnetic environments. They are simultaneously exposed to heavy magnetic fields from traction motors and transformers, high-voltage arcing from pantographs, and localized radio frequency interference from passenger electronic devices. None of these emissions should degrade sensitive control systems or driver displays.

To ensure electromagnetic immunity, EN 50155 references the collateral standard EN 50121-3-2 (Railway Applications – Electromagnetic Compatibility – Rolling Stock – Apparatus). This standard establishes strict limits for radiated and conducted emissions, as well as overvoltage and transient surge resistance. Compliance typically requires integrated EMC filtering to protect internal converter circuitry and absorb unwanted noise.

For historical reasons, a wide variety of supply voltages are used across global rail networks. The most common nominal ratings are 24VDC, 48VDC, 72VDC, 96VDC, and 110VDC. While 110VDC is commonly used on heavy rail trains, lower voltages ranging from 24V through 48V are typically found on light railways, trams, and trolleybuses. The latest version of EN 50155 defines seven standardized DC voltages including maximum and minimum transients to categorize these systems. To satisfy these varying input requirements without multiplying stock keeping units, railway application developers often opt for ultra-wide input 10:1 or 12:1 converters, which cover the entire input voltage spectrum using just one converter model.

Nominal Input Voltage	EN50155			RECOM RPxx-FR Serie
	Input Range	Min. Input (0,1s)	Max. Input (1s)	Input Range	Min. Input	Max. Input (1s)
24V	16.8-30V	14.4V	33.6V	9-36V	9V	50V
48V	33.6-60V	28.8V	67.2V	18-75V	18V	100V
72V	50.4-90V	43.2V	100.8V	43-160V	43V	170V
96V	67.2-120V	57.6V	134.4V	43-160V	43V	170V
110V	77-137.5V	66V	154V	43-160V	43V	170V

EN 50155 states that nominal input voltages may fluctuate continuously between 0.7 and 1.25 times the rated voltage, while permitting short-term deviations between 0.6 and 1.4 times nominal. In practice, this means a 48V DC/DC converter must reliably handle an operational range from 28.8V to 67.2V. While 4:1 converters were long considered the practical limit for efficiency and cost-effectiveness, RECOM has redefined these boundaries with its latest ultra-wide input voltage DC/DC converters. Selected converters feature broad 10:1 or 12:1 input ranges, enabling a single module to cover all common railway voltage ratings, including worst case transients.

DC/DC railway converters are commonly categorized by standard "brick" dimensions, though smaller DIP24, 1”x1”, and 2”x1” footprint packages are widely used for lower power board-level distribution. Standard industry footprints include half-bricks (2.3 x 2.4 x 0.35 inches) and quarter-bricks (2.3 x 1.45 x 0.35 inches). Modern switched-mode power supplies in the quarter-brick format can now deliver electrical power outputs of 250W or higher, significantly improving power density compared to older designs and freeing up valuable space for additional system features. Furthermore, because these packages follow standardized footprint dimensions, they can simplify mechanical replacement, but pinout and electrical compatibility must still be verified.