Dual 400 Hz AC & 28V DC Ground Power Units

A dual 400 Hz AC and 28V DC ground power unit is a combined power solution designed to provide both high-frequency alternating current and low-voltage direct current for aircraft on the ground. The 400 Hz AC output powers systems such as avionics, lighting, and climate control, while the 28V DC output supports batteries, communications equipment, and emergency systems. Having both outputs in one unit streamlines ground operations and eliminates the need for separate GPUs.

Aircraft systems require different power types depending on their function. High-frequency 400 Hz AC is standard for most onboard electronics and operational systems, while 28V DC powers battery charging, start functions, and certain critical safety devices. A dual GPU allows technicians to service both systems without switching between separate power sources, saving time and improving workflow efficiency.

Dual AC and DC GPUs are versatile and compatible with a wide range of aircraft, from business jets and regional airliners to larger commercial aircraft. The combination of power outputs ensures support for both small aircraft with lighter loads and larger models with more complex systems. This flexibility makes them ideal for operators who service mixed fleets.

Combining both power outputs into one GPU eliminates the need for multiple ground power units, reducing equipment costs, storage requirements, and operational complexity. It also simplifies setup in maintenance bays or on ramps, allowing technicians to connect and service all necessary systems from one location. This integration improves safety, efficiency, and productivity during aircraft servicing.

Yes, dual AC and DC GPUs are available in portable trailer-mounted designs and stationary configurations, depending on operational needs. Portable models are ideal for ramp or remote servicing, while stationary units are better suited for fixed maintenance bays or hangar operations. Both types offer durable construction and easy operation for dependable performance.

Solid-state dual GPUs use a fixed electrical power source to deliver AC and DC outputs, making them ideal for hangar use with consistent 3-phase input voltage. Diesel-powered units generate their own power, offering greater mobility and independence from electrical infrastructure. Choosing between the two depends on your facility layout, mobility requirements, and available power sources.

Yes, by supplying all necessary ground power directly, dual AC and DC GPUs reduce the need to run the aircraft’s auxiliary power unit (APU) during maintenance or preflight preparation. This helps lower fuel consumption, reduce engine wear, and minimize noise and emissions in hangar or ramp areas. Over time, this can result in significant operational cost savings.

Customization options include extended input and output cable lengths, dual-output configurations for servicing multiple aircraft, and the addition of integrated 28V DC modules on certain models. These upgrades allow operators to tailor the GPU to their specific maintenance procedures, aircraft types, and facility requirements. PJi can work with you to design the ideal configuration.

Longer cables increase reach and flexibility when servicing aircraft in large hangars or on ramps, allowing power to be delivered without moving the unit as often. However, cable length should be chosen carefully to minimize voltage drop and maintain optimal performance. PJi offers guidance on selecting the correct cable length for your application.

Many diesel-powered dual GPUs are designed for outdoor ramp operations, with weather-resistant housings and robust construction. Solid-state units are generally better suited for indoor hangar environments, though some models offer protective enclosures for limited outdoor use. Always review manufacturer specifications to ensure the unit meets your operational environment.

By providing both required power types simultaneously, these GPUs eliminate downtime caused by switching equipment or repositioning units. Technicians can perform multiple system checks, power-ups, and servicing tasks in one session, streamlining the maintenance workflow. This capability is particularly valuable for quick turnarounds and time-sensitive operations.

Routine maintenance includes inspecting cables, connectors, and control panels, and checking power output accuracy. Diesel-powered units also require regular engine servicing, fluid changes, and filter replacements. Proper maintenance ensures consistent performance and extends the service life of the equipment.

Yes, many models are compatible with both civil and military aircraft, as 400 Hz AC and 28V DC power standards are widely used across aviation sectors. Operators servicing mixed fleets benefit from the flexibility of a dual-output GPU that meets the needs of diverse aircraft types. Always verify voltage and connector specifications before use.