A2 400Hz GPU Purchase Description.pdf

PRODUCT DESCRIPTION & SALIENT

CHARACTERISTICS

MOBILE SOLID-STATE GROUND POWER UNIT (GPU)

Prepared For: Hangar & Flightline Maintenance Support (UH-60M Blackhawks)

Reference Model: Unitron PwrKart UFC-45M or Equal

Date / Version: May 2026 / Version 1.0

1. Scope of Requirement

This document defines the salient physical, functional, and electrical performance characteristics required for a mobile, shore-powered (electric) solid-state Ground Power Unit (GPU) / Frequency

Converter. The primary purpose of this equipment is to provide clean 400 Hz AC ground electrical power to support hangar and flightline maintenance, pre-flight troubleshooting, and servicing of military aircraft (specifically UH-60M Blackhawks).

The equipment will be procured on a competitive basis. The target benchmark configuration is the

Unitron PwrKart UFC-45M (CAGE: 12175). Any alternative model proposed must meet or exceed the performance parameters outlined below.

BENCHMARK CONFIGURATION (Brand Name or Equal):

• Manufacturer: Unitron (CAGE: 12175)

• Model: PwrKart UFC-45M

• Classification: Mobile Solid-State Ground Power Unit (GPU) / Frequency Converter

2. Electrical Specifications

2.1 Output Power Quality (AC)

The Ground Power Unit must deliver high-quality, stable AC power conforming to strict military aviation standards. The primary requirement is 400 Hz AC output; this unit must not be a DC-only power supply.

Parameter Specification Requirement

Power Rating 45 kVA continuous duty at 0.8 to 1.0 Power Factor (PF).

Product Description: Mobile Solid-State GPU (UFC-45M or Equal)

Parameter Specification Requirement

AC Output Voltage 115/200 VAC, 3-Phase, 4-wire (wye configuration), 400 Hz.

Voltage Regulation ±1.0% or better under all steady-state load conditions up to 100% rated capacity.

Harmonic Distortion Total Harmonic Distortion (THD) must not exceed 2.0% maximum on a linear load.

Aircraft Power Quality Standard Must fully comply with MIL-STD-704F (Aircraft Electrical Power Quality Standards) to prevent damage to sensitive avionics.

Output Protection Must include automatic over/under-voltage, over/under-frequency, overload, and short-circuit protections with automatic contactor disconnects.

DC Capability This unit must not be a DC-only power supply. The primary requirement is high-quality 400 Hz AC output.

2.2 Input Power Requirements

The GPU must operate strictly on facility electrical power. No internal combustion engines (diesel or gasoline) are permitted.

Parameter Input Requirement

Power Source (No Fuel) The unit must not be diesel or gasoline-powered. It must operate strictly on electrical utility/facility power.

Input Voltage Compatibility 380V to 480V AC, 3-Phase, 50/60 Hz.

Protection Integrated transient surge protection (conforming to IEEE C62.41 or equivalent) and phase rotation/loss detection.

3. Physical, Mechanical & Environmental Requirements

3.1 Configuration & Mobility

The unit must be designed for ease of movement and durability in demanding hangar and flightline environments.

Feature Physical Requirement

Mobility Must be a heavy-duty, manually maneuverable mobile cart configuration (towable/hand-steerable).

Tires Maintenance-free, flat-free, puncture-resistant solid tires (minimum 10-inch diameter) suitable for movement across concrete hangar floors and rugged flightline/asphalt ramp areas.

Enclosure Fully weather-protected, corrosion-resistant outdoor housing matching NEMA 3R, NEMA 3SX, IP55, or equivalent performance specifications.

3.2 Acoustics & Safety

Acoustic limits and safety interlocks must protect personnel and aircraft systems during operation.

Safety Aspect Requirement Details

Noise Restrictions Low noise output designed for safe indoor hangar operation. Noise levels must not exceed 65 dBA at 5 feet under full load conditions.

Safety Interlocks Standard aircraft safety interlock capability (utilizing 28.5 VDC EF interlock signals from the aircraft plug) to ensure power is only supplied when a secure connection is made.

3.3 Cable Assemblies

Heavy-duty, high-flexibility cables must be provided to ensure adequate reach and reliable power delivery.

Cable Type Minimum Length Specification / Connector

AC Input Cable Minimum 100 feet Flexible utility input power cable equipped with a heavy-duty facility-matched plug.

AC Output Cable Minimum 60 feet Banded, multi-conductor, high-flexibility 400 Hz output cable equipped with a standard molded 400 Hz aircraft-compatible connector plug.

4. Control Interface & Diagnostic Systems

The control system must provide intuitive operator controls, comprehensive diagnostics, and robust safety listings.

System Component Technical Specification

Operator Interface Integrated digital touch-screen microprocessor control panel that provides real-time displays of output voltage, current, and frequency on all phases.

Diagnostics Built-in Maintenance Diagnostic System / Built-In Test Equipment (BITE) capable of detailing active faults, historical error logs, and system health status.

Emergency Stop Easily accessible, weatherproof physical “E-Stop” push-button mounted externally on the unit.

Safety Listing Must be ETL or UL/CSA listed (under UL 1012 or equivalent standard for power supplies).