The following is a brief introduction to the US Military standard MIL-STD-810, as used to define the testing methodology for, and results required for acceptance of, rugged power conversion products.
MIL-STD-810 is a series of performance and manufacturing guidelines established by the US Department of Defense for military and commercial equipment and their applications. These guidelines specify allowabel parts and enviromental condition ranges in which a power supply, DC-DC converter or a DC-UPS must be able to operate compliance, to the specifiacion required.
MIL-STD-810 is a generally accepted standard of ruggedisation testing and compliance for most military equipment in ground mobie applications.
The MIL-STD-810 test method is used to generate confidence in the environmental worthiness and overall durability of ‘material system’ design. The testing process follows guidelines, which include program documentation, program roles, test standards, and laboratory test method guidelines for all categories.
The laboratory test methods are broken down into 24 categories and procedures (specific tests or levels) appropriate to the environment in which the equipment is expected to be used. The compliance test categories are shown overleaf.
The actual tests are carried out according to pre-defined test plans and criteria. The tests can be laboratory or natural environment field tests, or a combination, whichever applies. The test procedure is dependent on the environment tested. The procedure(s) and its execution provide the basis for collecting the necessary information.
After completion of each environmental test, the test data is examined and recorded in accordance with material specifications and program guidelines. A final test report will be created for each test, which includes an analysis of the test results. This report will then be available to the customer.
Some products will carry a MIL-STD SIDE rating and some may state they are MIL-STD 810F compliant. The Latest MIL-STD-810G is a revision of MIL-STD 810F and SlOE. The tests and methods are basically the same but much of the standard has been rewritten to provide clearer direction.
When selecting a rugged product, it is essential to check whether it is ‘designed to meet’, tested or compliant with MIL-STD-810. Mid-Eastern Industries has products available in all the above categories including custom products designed to your exact specifications. Contact the factory for your exact needs.
Remember — not all ‘rugged’ product are created equal! Mid-Eastern Industries has the “right” product for your exact needs.
Example tests and procedures
Mechanical Shock To determine the ability to withstand mechanical shocks from suddenly applied forces or an abrupt change in motion produced by handling, transportation or field operation.
Standard: MIL-STD-810F Method 514.3, category C.
• Environment: 75 g 11 ms saw tooth shock, 3± shock/axis, 3 axis, 18 total.
Altitude
To observe low air pressure effects on either operational or non-operational design parameters.
Standard: MIL-STD-810F, Method 500.2, Procedure I & II
• Environment: 40,000 ft. and 70,000 ft. operational
Explosive Atmosphere
To determine the ability of equipment to operate in the presence of an explosive atmosphere.
Standard: MIL-STD-810F, Method 511.4, Procedure I, operational
* Environment: Fuel-Air Explosive Atmospheres
Humidity
A humidity test simulates the moisture-laden air found in tropical regions.
Standard: MIL-STD-810F, Method 507.4 Procedure I, Cycle I
• Environment: 240 hours, 95% RH
Mechanical Shock
To determine the ability to withstand mechanical shocks from suddenly applied forces or an abrupt change in motion produced by handling, transportation or field operation.
Standard: MIL-STD-S1OF Method 514.3, category C.
• Environment: 75 g 11 ms saw tooth shock, 3± shock/axis, 3 axis, 18 total.
Random Mechanical Vibration
To evaluate the construction, materials and mounting of the device for ruggedness.
Standard: MIL-STD-810F Method 514.5 and MIL-HDBK-344A
• Environment: Vibration step from 21 — 41 g.
Temperature Humidity Bias
An operational test that evaluates the reliability of the device package in humid environments.
Standard: MIL-STD-810F, Method 507.3
• Environment: 85°C, 85°/s RH, high line input voltage
Fungus
To determine if a material (or materials) will support the growth of specific fungi.
Standard: MIL-STD-S1OF, Method 508.4 Section U
• Environment: Severe climate conditions
Salt Fog
To determine the resistance of the equ~ornent to the effects of a salt atmosphere, primarily
Standard: MIL-STD-810F, Method 509.1 Procedure
• Environment: Salt fog harsh environment
Categories
| Environment | MIL-STD 810F |
| Low Pressure (Altitude) High Temperature Low Temperature Temperature Shock Contamination by Fluids Solar Radiation (Sunshine) Rain Humidity Fungus Salt Fog Sand and Dust Explosive Atmosphere Immersion Acceleration Vibration Acoustic Noise Shock Pyroshock Acidic Atmosphere Gunfire Vibration Temperature, Humidity, Vibration, and Altitude Icing/Freezing Rain Ballistic Shock Vibro-Acoustic/Temperature |
Method 500.4 Method 501.4 Method 502.4 Method 503.4 Method 504 Method 505.4 Method 506.4 Method 507.4 Method 508.5 Method 509.4 Method 510.4 Method 511.4 Method 512.4 Method 513.5 Method 514.5 Method 515.5 Method 516,5 Method 517 Method 518 Method 519.5 Method 520.2 Method 521.2 Method 522 Method 523.2 |
