Length: 2 Days
MIL-STD-704 Training | Aircraft Electrical Power Characteristics, MIL-STD-704F Version
MIL-STD-704 establishes the requirements and characteristics of aircraft electric power provided at the input terminals of electric utilization equipment.
MIL-STD-704 is a Department of Defense standard that describes a standardized power interface between a military aircraft and its equipment and carriage stores.
The purpose of the MIL-STD-702 interface standard is to ensure compatibility between the aircraft electric system, external power, and airborne utilization equipment and establishes the requirements and characteristics of aircraft electric power provided at the input terminals of electric utilization equipment.
One of the more important things to keep in mind about MIL-STD-704 is that compliance is not exactly simple. Products must prove they can function effectively under extreme conditions, and customers may subject them to a variety of different tests to see how well they hold up and how those conditions affect them.
MIL-STD-704 covers the power generation system by citing the requirements that the power system is to provide at the utilization equipment power terminals. The testing evaluates the utilization equipment for compatibility with the cited performance of the power system.
Among topics the MIL-STD-704 standard covers include abnormal operation, emergency operation, and load characteristics for both AC and DC power systems.
MIL-STD-704 was issued in October 1959, as a standard superseding the engineering document MIL-E-7894 dealing with aircraft electrical power. The initial MIL-STD-704 considered only 28 Vdc and 115/200 Vac at 400 Hz from a three-phase, four-wire, “y” source.
The requirements were based on the available technology for power generation and distribution without undue weight and volume demands within the airframe capacity.
Revisions have been made over the years to implement new requirements, add voltage ranges, clarify and correct errors, update limits and establish more standardized test methods.
In addition to new revisions, change notices were released to make corrections between revision releases.
MIL-STD-704 Training Course by Tonex
MIL-STD-704 Training, Aircraft Electrical Power Characteristics, covers details of standardized power interface between a military aircraft and its equipment and carriage stores covering interfaces such as: voltage, frequency, phase, power factor, ripple, maximum current, electrical noise and abnormal conditions (overvoltage and undervoltage), for both AC and DC systems.
Learn about MIL-STD-704 requirements, testing and measurements to ensure compatibility between the aircraft electric system, external power, and airborne utilization equipment.
MIl-STD-704 training course covers requirements and characteristics of AC and DC power for aircraft provided at the input terminals of electric utilization equipment including test methods and procedures for determining airborne utilization equipment compliance with the electric power characteristics requirements defined herein. Electromagnetic interference and voltage spikes are not covered by this standard.
To ensure that aircraft electronics and other electrically-powered equipment will operate reliably, tests under extreme power conditions are required: Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics are covered including:
- Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics
- Single Phase, 400 Hz, 115 Volt
- Three Phase, 400 Hz, 115 Volt
- Single Phase, Variable Frequency, 115 Volt
- Three Phase, Variable Frequency, 115 Volt
- Single Phase, 60 Hz, 115 Volt
- 270 VDC
- 28 VDC
Power testing is required to demonstrate compatibility of avionics with aircraft electrical power under operating conditions and power groups of MIL-STD-704.
Who Should Attend
Learning Objectives
Upon completion of MIL-STD-704 training, the attendees will:
- Learn about MIL-STD-704 generic and detailed requirements
- Learn about MIL-STD-704 limits and abnormal operation
- Familiarize with MIL-STD-704 testing equipment
- Understand how the testing and measurements of MIL-STD-704 works
- Explore MIL-STD-704 “Compliance Test and Measurement Options”
- Avoid common errors in testing procures of MIL-STD-704
Course Agenda
MIL-STD-704 Overview
- MIL-STD-704 Tools
- MIL-STD-704 Criterial
- MIL-STD-704 Capable System Testing and Measurements
- MIL-STD-704 Testing and Measurement Criteria
MIL-STD-704 Defined Abnormal operation
- AC voltage
- Aircraft electric power systems
- Crest factor
- Current
- Current modulation
- DC voltage
- Distortion
- Distortion factor
- Distortion spectrum
- Electric starting operation
- Emergency operation
- External power source
- Frequency
- Frequency modulation
- Load unbalance
- Normal operation
- Overfrequency and underfrequency
- Overvoltage and undervoltage
- Point of regulation
- Power factor
- Pulsed load
- Rate of change of frequency
- Ripple
- Steady state
- Transfer operation
- Transient
- Utilization equipment
- Utilization equipment terminals
- Voltage modulation
- Voltage phase difference
- Voltage unbalance
MIL-STD-704 General Requirements
- Aircraft electric power system requirements
- Aircraft electric power system performance
- Electric power source characteristics
- Protective devices
- Aircraft utilization equipment requirements
- Power compatibility
- Operation
- Normal operation
- Abnormal operation
- Transfer operation
- Emergency operation
- Starting operation
- Power failure
- AC power utilization
- External power source requirement
- Test requirements
MIL-STD-704 Detailed Requirements
- Transfer operation characteristics
- AC power characteristics
- Type system
- Phase sequence
- Normal operation
- Abnormal operation
- Emergency operation
- DC power characteristics
- Type system
- 28 volts DC system
- Normal operation
- Abnormal operation
- Emergency operation
- Electric starting
- 270 volts DC system
- Normal operation
- Abnormal operation
- Emergency operation
- Load characteristics
- Grounding
- Load unbalance
- Power factor
- Polarity or phase reversal
- Multiple input terminals
MIL-STD-704 Detailed Testing and Measurements Procedures
- Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics
- Single Phase, 400 Hz, 115 Volt
- Three Phase, 400 Hz, 115 Volt
- Single Phase, Variable Frequency, 115 Volt
- Three Phase, Variable Frequency, 115 Volt
- Single Phase, 60 Hz, 115 Volt
- 270 VDC
- 28 VDC
Guidance for Test Procedures
- MIL-HDBK-704-1, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics
- MIL-HDBK-704-2, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, Single Phase, 400 Hz, 115 Volt
- MIL-HDBK-704-3, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, Three Phase, 400 Hz, 115 Volt
- MIL-HDBK-704-4, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, Single Phase, Variable Frequency, 115 Volt
- MIL-HDBK-704-5, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, Three Phase, Variable Frequency, 115 Volt
- MIL-HDBK-704-6, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, Single Phase, 60 Hz, 115 Volt
- MIL-HDBK-704-7, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, 270 VDC
- MIL-HDBK-704-8, Guidance for Test Procedures for Demonstration of Utilization Equipment Compliance to Aircraft Electrical Power Characteristics, 28 VDC