This SAE Recommended Practice which defines the terms and tabulates the limits of the characteristics for various protective devices used in conjunction with 400-cycle ground power for civil aircraft is intended to assist the airlines in standardizing on 400-cycle protective systems. The limits found to be acceptable in the civil aircraft industry are presented.

This SAE aerospace recommended practice (ARP) covers the requirements for external ground power equipment supplying 115/200 V, three-phase, 400 HZ output power measured at the aircraft receptacle. All forms of 400 Hz ground power including mobile and fixed systems are addressed by this document. Modifications are made within the document for the new generation aircraft electrical systems, update the external document references and general updates and corrections.

This Recommended Practice outlines the electrical performance characteristics for a continuous duty, diesel or gasoline engine driven brushless alternator unit for supplying 400-Hertz electrical power to commercial transport aircraft. It is intended to assist the airlines in standardizing recommendations for various sizes and configurations of equipment and it is a guide for the preparation of detailed specifications. The unit is primarily intended to supply power to the aircraft during passenger loading and unloading, and during servicing operations. The combination of the equipment specified herein and the interconnecting cables(s) between the 400-Hertz alternator and the aircraft shall provide power characteristics at the aircraft receptacle which meet MIL-STD-704 requirements for Category "B" equipment. Other limits which are necessary to meet specific conditions must be specified by the purchaser.This ARP is obsolete and has been fully replaced by ARP5015A Ground Equipment - 400 Hertz Ground Power Performance Requirements. Use of this ARP for Ground Power Unit design may result in unsafe operation for the aircraft and the equipment.

This SAE Aerospace Information Report (AIR) describes the characteristics and effects of using no-break power transfer (NBPT) methods when switching between auxiliary-power unit (APU) and ground-power unit (GPU). The GPU may be: aPoint-of-use solid-state frequency converter, engine-generator, or motor-generator bCentral system powered by motor-generator or solid-state frequency converter.

This recommended practice outlines the general requirements of a continuous duty, electric motor-driven brushless alternator unit for supplying 400 Hz electrical power to high performance commercial transport aircraft. This specification is for a single motor-generator set with one or two outputs. The generator set will generate at the aircraft voltage of 115/200 volts. This unit may be used in a central system of small size or in hangar or electronic shop applications. Power characteristics of this unit at the receptacle will meet MIL-Standard-704 requirements. Other limits which are necessary to meet specific conditions must be specified by the purchaser.