Ground Power Unit (GPU) / 45 kVA · 400 Hz AC + 28.5V DC / Diesel-driven · Trailer-mounted / India

GPU · AIRCRAFT GROUND POWER

Ground Power Unit (GPU), rated to 45 kVA / 400 Hz.

A diesel engine-driven, trailer-mounted ground power unit that powers aircraft on the ground during maintenance and repair. Dual output — 400 Hz AC and 28.5V DC 800 A — is delivered simultaneously up to 45 kVA, under PLC control with a touchscreen HMI.

Request proposal Specifications

Ground Power Unit GPU 45 kVA trailer-mounted diesel aircraft ground power unit front view by Neometrix

Fig · 01 45 kVA Ground Power Unit · trailer-mounted · diesel engine-driven

Rated Power

45kVA

AC Frequency

400Hz

DC Output

800A @ 28.5V

Overload

50kVA / 5 min

Operating Temp

−32to +55°C

Overview

Two outputs, one mobile unit.

The Ground Power Unit gives external power to aircraft on the ground, so systems can be powered up for maintenance and repair work.

Ground power unit GPU rear louvred side view - 45 kVA 400 Hz aircraft ground power trailer by Neometrix

Fig · 02 Rear and louvred side · trailer chassis with integrated cable trays

This GPU has a dual output. The first is a 45 kVA AC supply of 200V line-to-line and 115V line-to-neutral, 150A, 400 Hz, four-wire system. The second is a 28.5V DC, 800A two-wire supply. Both are delivered simultaneously up to a maximum of 45 kVA.

A diesel engine coupled with a highly reliable alternator provides stable output to your aircraft. With a touchscreen control panel and interactive GUI, the unit is easy to operate and effortless to maintain. The AC unit can also be supplied with an additional 28.5V DC module for tools and appliances during aircraft maintenance.

45 kVA at 400 Hz, with 28V DC alongside.

Feature-rich software supports remote operation of the ground support equipment, with parameter details, fault alarms, alerts and a periodic maintenance schedule. The system is mounted on a portable, towable trolley with braking, for easy access across the ground.

Architecture

Six systems, one towable unit.

From the diesel-driven alternator to the PLC and HMI, each subsystem of the GPU is built for safe, stable aircraft power.

Sub · 01

Engine & Alternator

Diesel engine (Ashok Leyland) driving a high-speed Mecc Alte alternator at 2000 RPM for stable frequency and voltage under dynamic load.

Sub · 02

Voltage & Speed Control

An integrated Automatic Voltage Regulator (AVR) holds voltage steady, while electronic speed control keeps the 400 Hz frequency stable.

Sub · 03

PLC & HMI Control

PLC-based architecture manages operating logic, safety interlocks and sequencing; the HMI shows voltage, current, frequency, engine parameters and fault status.

Sub · 04

Power Distribution

Dual 400 Hz AC output circuits and dual 28V DC output circuits, with AC and DC outputs able to operate simultaneously.

Sub · 05

Electrical Control Cabinet

Integrated cabinet housing the PLC, ECU (Engine Control Unit), power meters, relay drivers and communication modules (RS485 / Ethernet).

Sub · 06

Chassis & Trailer

Heavy-duty fabricated steel body on a trailer with integrated cable trays, fuel tank and easy-access maintenance points; towable with braking.

Image Gallery

The GPU, from every side.

Rear, angled and front views of the Neometrix Ground Power Unit.

Ground power unit GPU rear louvred side - diesel-driven 45 kVA aircraft ground power trailer by Neometrix

Ground power unit GPU angled rear view with open service door showing access to control and maintenance points by Neometrix

Ground power unit GPU front view on white background - trailer-mounted 45 kVA 400 Hz unit by Neometrix

Fig · 03–05 Rear / louvred side, angled rear with open door, and front view

Video

The GPU in operation.

Video walkthrough of the Ground Power Unit.

Downloads

Catalog & design.

Product catalog and design document for the Ground Power Unit, available as PDF for procurement and technical review.

Catalog · General

Ground Power Unit — General Catalog

PDF

Ground Power Unit design document thumbnail

Design · 01

Ground Power Unit — Design 1

PDF

Specifications

Full technical parameters.

Key system parameters for the standard Neometrix 45 kVA Ground Power Unit.

Rated Power (400 Hz)	45 kVA @ cosφ 0.8
Overload Capacity	50 kVA (5 minutes)
AC Output	115V AC (3-phase); 200V L-L / 115V L-N, 150A, four-wire
Frequency	400 Hz
28V DC Output	28.5V, 800A continuous, two-wire
DC Overload	Up to 1200A
Engine Type	Diesel (Ashok Leyland)
Alternator	Mecc Alte
Speed	2000 RPM
Operating Temperature	−32°C to +55°C
Humidity	≤ 95%
Altitude	≤ 4000 m
Length	2400 mm
Width	1950 mm
Height	1320 mm
Weight	2300–2400 kg

Applications

Where it powers.

Used as a GPU in aircraft ground handling and GPU in aviation MRO facilities, it supports aircraft on the ground for maintenance and basic testing without starting their engines. It is designed around the aircraft's required power.

A · 01Aircraft ground power supply

A · 02Aircraft maintenance operations

A · 03Airport ground handling

A · 04Defence aviation support

A · 05Hangar operations

A · 06Avionics testing and pre-flight system checks

In Depth

The complete technical read.

Engineering narrative for aviation ground-support teams, procurement and maintenance managers.

Introduction

The 45 kVA Ground Power Unit (GPU) is a robust, trailer-mounted system engineered to provide reliable electrical power to aircraft during ground operations. It delivers both 400 Hz AC power — the standard frequency required by most aircraft systems — and 28V DC output for auxiliary and starting applications. This dual-output capability makes the unit versatile for aviation maintenance, servicing and operational readiness.

Power generation

At the core of the GPU is a diesel engine-driven alternator system. The engine drives a high-speed alternator, ensuring stable frequency and voltage output even under dynamic load conditions. An integrated Automatic Voltage Regulator (AVR) maintains consistent voltage levels, while electronic speed control ensures frequency stability in compliance with aviation standards.

Control & HMI

An advanced PLC-based control architecture manages all operational logic, safety interlocks and sequencing, ensuring safe startup, shutdown and continuous operation. The Human Machine Interface (HMI) provides real-time data — voltage, current, frequency, engine parameters and fault status — and allows intuitive control without direct interaction with internal control systems.

Power distribution

Dual 400 Hz AC output circuits
Dual 28V DC output circuits
Capability to operate AC and DC outputs simultaneously

The fully integrated electrical control cabinet houses the PLC, ECU (Engine Control Unit), power meters, relay drivers and communication modules, working together for precise monitoring, control and protection.

Key features

Provides 400 Hz AC and 28V DC power for aircraft ground operations.
45 kVA rated output with overload capability up to 50 kVA.
Stable 28V DC output delivering up to 800A continuous current.
PLC-based control system with advanced safety interlocks.
User-friendly HMI for real-time monitoring and system control.
Rugged diesel engine for reliable and continuous performance.
Wide operating temperature range from −32°C to +55°C.
Comprehensive protection with alarms, fault detection and emergency stop.

Safety & protection

Over-voltage and under-voltage protection
Frequency deviation protection
Overcurrent and overload protection
Emergency stop functionality
Fault detection and alarm logging via HMI

Construction & environment

The rugged chassis and body are built from heavy-duty fabricated steel. The unit is mounted on a trailer with integrated cable trays, fuel tank and easy-access maintenance points, designed for mobility and ease of deployment in airports, airbases and remote locations. It operates from −32°C to +55°C, in high humidity and at altitudes up to 4000 metres, suiting both civilian and defence aviation applications.

Optional 28V systems, communication interfaces (RS485 / Ethernet) and advanced monitoring capabilities enhance adaptability and integration into modern ground support infrastructure.

Conclusion

The Ground Power Unit combines high reliability, operational flexibility, advanced control systems and robust construction, making it one of the more dependable ground power units available as an aircraft ground power unit for defence and commercial aviation fleets.

FAQ

Common questions.

Plain-language answers from the engineering team.

Q · 01 What is a Ground Power Unit (GPU)?

A GPU supplies electrical power to aircraft during ground operations, so maintenance and basic testing can be done without starting the aircraft engines.

Q · 02 What output does this GPU provide?

It provides 400 Hz AC and 28V DC power. The AC output is 115V line-to-neutral (200V line-to-line), 150A, four-wire; the DC output is 28.5V, 800A, two-wire.

Q · 03 What is the rated capacity?

The unit delivers 45 kVA at 400 Hz (cosφ 0.8), with overload capacity up to 50 kVA for 5 minutes.

Q · 04 Can AC and DC outputs be used simultaneously?

Yes, both outputs can operate simultaneously within the 45 kVA power limit.

Q · 05 What engine and alternator are used?

A diesel engine (Ashok Leyland) drives a Mecc Alte alternator at 2000 RPM.

Q · 06 What is the operating temperature range?

−32°C to +55°C, with humidity up to 95% and altitude up to 4000 m.

Q · 07 Is the system safe to operate?

Yes, it includes multiple safety protections, alarms and an emergency stop button that stops the system immediately.

Q · 08 What control system is used?

A PLC-based system with an HMI interface is used.

Q · 09 What maintenance is required?

Periodic checks every 500 to 1000 operating hours.

Q · 10 Can it be used in hazardous zones?

No, it cannot be used in ATEX zones.

Q · 11 Does it support remote monitoring?

Yes, via communication interfaces such as RS485 and Ethernet.

Q · 12 Is it mobile?

Yes, it is trailer-mounted and towable with a braking system for easy mobility.

Get a proposal

Tell us your aircraft power
requirements.

The GPU is designed around the required power of your aircraft. Share your AC and DC load needs and site conditions and our team will configure the unit with you.

Request proposal +91 7777 876 876