Q Series | Bel Power Solutions

Input: Wide input (2:1)
Outputs: 5 to 48V
Power: 120 Watt
Tamb: -40 to +71°C
Dims: 168 x 111 x 20mm (3U x 4TE)
UL / CE EN62368-1 Approved
5 Year Warranty

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These extremely compact Melcher DC-DC Converters by Bel Power incorporate all necessary input and output filtering, signaling, and protection features, which are required in the majority of applications.

The converters provide important advantages such as flexible output power through primary current limitation, high efficiency, excellent reliability, very low ripple and RFI noise levels, full input to output isolation, negligible inrush current, overtemperature protection, and input over-/undervoltage lockout. The converter inputs are protected against surges and transients occurring on the source lines.

The converters are particularly suitable for rugged environment, such as railway applications. They have been designed in accordance with the European railway standards EN 50155 and EN 50121-3-2. The Q series of power supplies are Network Rail Approved. All printed circuit boards are coated with a protective lacquer.

The outputs are continuously open- and short-circuit proof. An isolated output Power Good signal and LEDs at the front panel indicate the status of the converter. Test sockets at the front panel allow for a check of the main output voltage.

Full system flexibility and n+1 redundant operating mode are possible due to virtually unrestricted series or parallel connection capabilities of all outputs. In parallel connection of several converters, automatic current sharing is provided by a single-wire interconnection.

As a modular power supply or as part of a distributed power supply system, the extremely low profile design significantly reduces the necessary power supply volume without sacrificing high reliability. A temperature sensor disables the outputs, if the case temperature exceeds the limit. The outputs are automatically re-enabled, when the temperature drops below the limit.

The fully enclosed, black-coated aluminum case acts as a heatsink and an RFI shield. The converters are designed for 19″DIN-rack systems occupying 3U/4TE only, but can also be chassis-mounted by means of four screws. It is possible to fit an additional heat sink.

Feature List

RoHS lead-free-solder and lead-solder-exempted products are available
Wide input voltage ranges up to 150 Vdc
1 or 2 isolated outputs from 3.3 to 48 Vdc
Class I equipment
Extremely high efficiency of up to 90%
Flexible output power
Excellent surge and transient protection
Outputs open- and short-circuit proof
Redundant operation, current sharing
Extremely low inrush current, hot swappable
Externally adjustable output voltage and inhibit
Electric strength test 2.1 kVdc
Very compact (<20 mm wide)
Railway standards EN50155 / EN50121 observed
Safety according to IEC/EN 62368-1, UL/CSA 62368-1
5 year warranty on -G versions