PowerGuard 115/200 VAC 400 Hz Military Static Frequency Converter — 60–400 Hz Variable Output

The PowerGuard Military 115/200 VAC 400 Hz Static Frequency Converter is a solid-state frequency conversion system that takes a 3-phase 360–440 VAC, 50–60 Hz supply and converts it to a variable 115–220 VAC, 60–400 Hz output. It was developed by TEDEG engineering to provide the reliable power conversion that defence and industrial applications depend on.

Many military systems are designed to run on 400 Hz power. Shipboard electronics, radar and fire-control subsystems, and some units fitted to land vehicles and mobile field systems fall into this group. At 400 Hz, transformers and motors can be smaller and lighter for the same power. Site and camp grids, however, supply 50–60 Hz. PowerGuard bridges that gap: it takes the grid supply and regenerates it at the voltage and frequency the equipment expects.

Two connection options are available for 400 Hz loads: star connection at 115 VAC (line-to-neutral) and delta connection at 115 VAC (line-to-line). An optional power distribution unit can be added at the output, so that power is distributed to different subsystems in a controlled way.

Conversion is entirely electronic; there is no rotating machine such as a motor-generator set. Steady-state voltage and frequency fluctuations are kept under control, and output quality is defined by harmonic distortion and modulation limits.

Electrical performance:

Protection:

• Phase-sequence protection
• Overload, short-circuit and over-temperature protection
• Steady-state voltage and frequency fluctuation control
• Output shutdown within 100–170 ms on over- or under-voltage

Monitoring and control:

• BIT (Built-In Test): Continuous status monitoring
• OLED display: Status on the unit itself
• RS-422: Remote control and data monitoring
• Real-time measurement: Live readout of input and output values
• Desktop remote control and monitoring software over Ethernet: Shows per-phase input and output currents, line-to-line voltages, and input and output frequency. It lists over- and under-voltage, overcurrent, frequency deviation, unbalanced load, heat-sink and cabinet temperature, emergency, open panel door, and fuse and contactor faults on the 115 V and 200 V outputs as separate alerts. Voltage selection, inverter start, output on/off, fault reset and silent mode commands are sent from the software.

Environmental and mechanical:

Military standards:

• MIL-STD-1399B: Technical standard compliance
• MIL-STD-1399-300B: Output voltage and frequency requirements
• MIL-STD-810G CHG-1: Environmental durability; passed at an ISO/IEC 17025 laboratory (report V 1731 23268 00 01 BE): temperature, solar radiation, rain, humidity, salt fog, vibration, shock
• MIL-STD-461G: EMI/EMC; passed (report A 1731 23268 00 01 BE): CE102, RE102, CS101, CS114, CS115, CS116, RS103

Defence:

• Naval platforms: Supplying shipboard 400 Hz equipment, with output voltage and frequency requirements defined to MIL-STD-1399-300B
• Radar and fire-control systems: Powering 400 Hz subsystems during maintenance, integration and testing
• Land vehicles and mobile field systems: Workshop and depot testing of vehicle-mounted 400 Hz units, and powering field systems
• Military camps and forward outposts: Power source at temporary bases
• Field operations: Fast power conversion in mobile operations
• Specialised military motors and power-intensive equipment: Mission equipment with high energy demand

Industrial and critical infrastructure:

• Test and calibration laboratories: Test equipment that needs precise power
• Production lines, heavy industry and automation: Large industrial motors and control systems
• Hospitals and data centres: Critical medical devices, servers and storage
• Emergency management: Transportable power source in disaster zones

On naval platforms the PowerGuard works as a 115/200 VAC 400 Hz power supply for shipboard equipment. It takes a 3-phase 360–440 VAC, 50–60 Hz supply and delivers 115 VAC at 400 Hz in star (line-to-neutral) or delta (line-to-line) connection; its output voltage and frequency requirements are defined to MIL-STD-1399-300B. What a naval integrator can check in the datasheet and test reports:

• Connection: star with a neutral conductor, or delta; output power factor at least 0.85 in star and 0.80 in delta
• Output quality: THD below 5%, frequency modulation max. 4 Hz, voltage modulation max. 2.5 Vrms
• Transients and protection: steady state within 200 ms; output shut down within 100–170 ms on over- or under-voltage; phase-sequence, overload, short-circuit and over-temperature protection
• Environmental and EMC tests: salt fog, humidity, rain, solar radiation, vibration and shock passed under MIL-STD-810G CHG-1, and radiated emissions (RE102) passed against the Navy mobile and Army limits of MIL-STD-461G, both at an ISO/IEC 17025 laboratory
• Monitoring: BIT, OLED display, RS-422 and the Ethernet desktop software with per-phase current, line-to-line voltage, input and output frequency, and fault and warning readings

Platform-specific mounting and interface requirements are assessed at project stage. Where shipboard loads need 60 Hz and 400 Hz on separate channels, see the PowerGuard Outdoor 60/400 Hz Military Frequency Converter.

Both reports were issued by Consept Europe Kft., accredited to ISO/IEC 17025, at its Gebze test site, with the verdict that the product passed all tests in scope. The full reports are shared on request.

MIL-STD-810G CHG-1, environmental — report V 1731 23268 00 01 BE (21 March 2025):

MIL-STD-461G, EMI/EMC — report A 1731 23268 00 01 BE (20 March 2025):

PowerGuard brings a variable 60–400 Hz output, a choice of star or delta connection, BIT, OLED and RS-422 monitoring, and Ethernet-based desktop software together in a single cabinet. Because one unit can supply both 400 Hz equipment and 60 Hz loads, there is less need to carry separate converters for different missions. With the optional power distribution unit, the converter becomes a power platform that distributes energy to subsystems in a controlled way.

If you need an outdoor solution that delivers 60 Hz and 400 Hz on separate channels, see the PowerGuard Outdoor 60/400 Hz Military Frequency Converter. Where a vehicle or platform needs the transformer, frequency conversion and distribution in one cabinet reporting over CAN-Bus, see the frequency converter transformer system. On radar and missile-launch platforms, antenna and launcher pedestal motors can be driven by the Mil-Drive-55 military motor drive. All options are listed under Frequency Converters, Motor Drives & Military UPS Systems.

Corporate assurance: TEDEG Defence is an approved supplier of ASELSAN, Roketsan and the Turkish Ministry of National Defence (MSB), with NATO supplier registration under NCAGE: TM885.