Converters in a System create the Ultimate Majortel DC/DC Package

Converters in a feature rich power conversion system offer flexibility and redundancy to the critical network architecture. The Majortel 1U Converter system is a compact rack mounted design that supplies critical equipment solutions requiring 24V or 48V dc from a 125-130V dc power source or electric utility provider substation battery.  Each dc-dc converter system is designed to occupy a true 1U (1.75” height) rack space in a standard 19” width rack and under 11” deep.  Fault-Tolerant design installations will include two compact, high density and reliable high-frequency 25 amp dc-dc converters, for a total system capacity configuration of 50A output in the single selected voltage for the application. Power Industry User approvals for the converter product continue to grow, since the first electric utility market application several years ago in 2013. link to: “Making the Grade” #powerquality

Majortel Converters Overview


** Majortel 130V to 48V DC/DC Converter System

  • Wide-range 100-300V DC Input
  • 24V or 48V DC Output
  • User Selectable Output Capacity 25 or 50 amp
  • Extended Temperature Operations, up to 75°C
  • Programmable Alarms with dry-contacts
  • Integrated Remote Communication package
  • Easy, manageable monitor screen
  • Quick check LED Indications

The dc to dc converter system includes a simple Load 1 and Load 2 breaker distribution to support multiple isolated output feed configurations. The power conversion modules automatically load-share to support either and both connected loads.
link to: “Load A/B Dual-Power Circuits” #FaultTolerantPower

A conversion power system capacity is user configurable for 25A or 50A** applications. The dc to dc converters are hot-swap capable facilitating field upgrades from 25 to 50 amps in a matter of minutes or module replacement without service disruption to the critical infrastructure equipment. link to: “Majortel DC/DC Converter Circuit”

For more detailed specifications about all Majortel DC/DC Converter products, click here or the part number below. Most popular model is 125vdc to 48vdc system for grid communication upgrade designs.

DC-DC Converters Amp Watt Input / Output Converter Power Module Loads
MTD48/25-130-1U 25 1450 130 48 MTDC48/25 x 1 2
MTD48/50-130-1U 50 2900 130 48 MTDC48/25 x 2 2
MTD24/25-130-1U 25 800 130 24 MTDC24/25 x 1 2
MTD24/50-130-1U 50 1600 130 24 MTDC24/25 x 2 2

The MTS-Com centralized man-to-machine interface is included with every system. The integrated controller monitors critical system conditions and facilitates system programming. The controller functions include fault alarms, alarm threshold adjustments, voltage adjustments and overall system status. This easy to read screen allows the user to program the unit with only a few buttons. The unit toggles audible alerts, LEDs and Form-C contact closures based on the system monitored parameters. link to: “Controllers for Majortel”

Technical Application and Installation Considerations

The power product output is factory-set to the default voltage and can be user adjusted to meet application requirements. Although the installation task is straightforward, study the installation manual information carefully for optimum performance. A user manual (IOM: Installation and Operations) ships in every system carton.

All connections to the power product are made to the terminal blocks located on the rear of the chassis. Labels identify the details of the terminal connections. The cabling (connection wire) and rack mount screws are user-furnished items. These items are custom to each installation and therefore not supplied with the power product.

Key Considerations: The converter is isolated between the input and output, permitting the following:

1. The converter dc input can be positive ground, negative ground, or floating.
2. The converter dc output is isolated from the input and floating. Neither positive nor negative side of the output is connected to the chassis ground.

Converters Design Architecture

The Majortel DC-DC Isolated Power Converter is a single rack unit DC-DC system. Each system is designed with advanced power electronics and microprocessor technology offering the following features:

High-Frequency Architecture

Our Majortel DC Converter Module (MTDC) architecture is a field-proven, versatile line of industrial grade converters providing regulated, filtered and protected output, suitable for applications requiring low ripple and isolated dc output.

Galvanic Isolation

Each converter module is galvanically isolated from input-to-output and floating, therefore permitting the following:

A. The dc input to the converter can be positive ground, negative ground, or floating. Neither positive nor negative side of the input is connected to the chassis ground.
B. The converter dc output is isolated from the input and floating. Neither positive nor negative side of the output is connected to the chassis ground.
C. Dielectric Isolation Rating: 4242 Vdc / 3K Vac Input-to-Output

Operational Efficiency & Low Noise

The MTDC power module offers an advanced soft-switching design, which increases operating efficiency and reduced switching noise. Ripple is reduced to less than 10 mV RMS in applications without battery.

Advanced Protection Features:

  • Input reverse polarity-proof protection; no fault damage
  • Majortel Controller

    MTS Com

  • Input over/under voltage protection
  • Output overload protection – Current Limit
  • Output over/under voltage protection
  • Output short circuit protection
  • Internal over temperature protection
  • Forced-air cooling with thermostatic control

Output Circuit Breaker Design
Individual circuit breakers facilitate connection of multiple loads. Each over current protection device (OCPD) is rated for full system output at 50 amps. During system commissioning, switch ON each Load 1 & Load 2 output breaker. Any “active” load alarms will clear when the toggle position sensor is confirmed by the controller. About a mid-trip breaker design; the alarm auxiliary switch will only signal, to the controller, on a fault condition in the OCPD. For example, the breaker toggle will be physically tripped by the over-current condition then stop at a mid-point in the sweep to indicate a “tripped” condition. Moving the toggle in a full sweep, from ON to OFF, will not create an alarm in the system.

These systems have been field tested, approved and deployed from ISO public power operators to leading IOU electric power utility corporations deploying “Utility Smart-Grid” technology for the future.

Contact us to discuss your application with this power conversion system.