EMC
Radio
MIL-STD-810 F/G Standards
Telecom
Environmental
Product Safety
Presented by Mr. Vladimir Kogan, Group Manager Environmental
and Michael Mirin, Environmental Test Engineer.
28-June-11
International Approvals
jpg. Files
Seminar AGENDA

MIL-STD-810 introduction 09:00 – 09:30, Vladimir Kogan
 MIL 810 overview – What it is
 MIL 810 tests :Mechanical, Climatic, Special
 MIL 810 F vs. MIL 810G

Explosive Atmosphere 09:30 – 10:30, Vladimir Kogan
 Scope, Purpose and Test Process


Break 10:30 – 10:45
Mechanical testing 10:45-11:30, Michael Mirin
Scope, Purpose and Test Process

Altitude and Decompression test , 11:30 – 12:50, Vladimir Kogan
Low, High Temperatures and Humidity testing
Scope, Purpose and Test Process




Lunch break, 13:00-14:00
Explosive & Mechanical presentation/demonstration 14:00 -15:00
Explosive & Mechanical presentation/demonstration 15:00 -16:00
Q & A 16:00
MIL-STD-810 F/G Standards Seminar
WELCOME!
MIL-STD-810 F/G Introduction
MIL-STD-810 F/G Introduction
Scope of the standard
This standard contains materiel acquisition program planning and engineering direction
for considering the influences that environmental stresses have on materiel throughout all
phases of its service life. It is important to note that this document does not impose
design or test specifications.
“MIL-STD-810G, DEPARTMENT OF DEFENSE TEST METHOD STANDARD:
ENVIRONMENTAL ENGINEERING CONSIDERATIONS AND LABORATORY TESTS
(31 OCT 2008) – USA”
MIL-STD-810 F/G Introduction
Broad range of environmental conditions that include:
•
•
Low pressure for ALTITUDE testing;
•
•
•
•
•
•
•
•
•
•
•
RAIN (including wind blown and freezing rain);
Exposure to HIGH AND LOW TEMPERATURES plus TEMPERATURE SHOCK (both operating
and in storage);
HUMIDITY,
FUNGUS,
SALT FOG for rust testing;
SAND AND DUST exposure;
EXPLOSIVE ATMOSPHERE;
LEAKAGE;
ACCELERATION;
SHOCK and transport shock (i.E., Triangle/sine/square wave shocks);
GUNFIRE VIBRATION;
RANDOM VIBRATION.
MIL-STD-810 F/G Introduction
History and rationale
MIL-STD-810 F/G Introduction
This standard is approved for use by all Departments and Agencies of the Department of
Defense (DoD). Although prepared specifically for DoD applications, this standard
may be tailored for commercial applications as well.
•
MIL 810G includes significant changes vs. 810F
• One new additional Part
• 5 New Test Methods
MIL-STD-810 F/G Introduction
The MIL- STD includes 3 parts
MIL-STD-810 F/G Introduction
Part 3:
Part 1:
WORLD CLIMATIC
REGIONS –
GUIDANCE
ENVIRONMENTAL
ENGINEERING
PROGRAM
GUIDELINES
Part 2:
LABORATORY TEST
METHODS
Describes management,
engineering, and technical
roles in the environmental
design and test tailoring
process.
It focuses on the process of
tailoring materiel design and
test criteria to the specific
environmental conditions a
materiel item is likely to
encounter during its service
life
MIL-STD-810 F/G Introduction
Part One Environmental engineering program guide
Task 401 - Environmental Engineering
Management Plan (EEMP)
Task 402 - Life Cycle Environmental Profile
(LCEP)
Task 403 - Operational Environment
Documentation (OED)
Task 404 - Environmental Issues/Criteria List
(EICL)
Task 405 - Detailed Environmental Test Plans
(DETP)
Task 406 - Environmental Test Reports (ETR)
MIL-STD-810 F/G Introduction: Roles
MIL-STD-810 F/G Life Cycle (Transportation)
MIL-STD-810 F/G Life Cycle (Operational)
MIL-STD-810 F/G Introduction
Part 3:
Part 1:
WORLD CLIMATIC
REGIONS –
GUIDANCE
ENVIRONMENTAL
ENGINEERING
PROGRAM
GUIDELINES
Part 2:
LABORATORY TEST
METHODS
Contains environmental
laboratory test methods to
be applied according to the
general and specific test
tailoring guidelines
described in Part One.
MIL-STD-810; 1962
Test methods
The MIL-STD-810 test series contains environmental laboratory test methods that are applied using specific test tailoring
guidelines described within the standard.
MIL-STD-810 F/G :
Part two Test methods “F”
MIL-STD-810 F/G:
Part two Test methods “G”
MIL-STD-810 F/G:
Part two Test methods comparison: 1962 vs. “G”
MIL-STD-810 F/G Introduction
Contains a compendium of climatic
data and guidance assembled from
several sources.
Part 3:
Part 1:
WORLD CLIMATIC
REGIONS –
GUIDANCE
ENVIRONMENTAL
ENGINEERING
PROGRAM
GUIDELINES
Part 2:
LABORATORY TEST
METHODS
Part Three provides planning guidance
for realistic consideration of climatic
conditions in the research,
development, test, and evaluation
(RDTE) of materiel and materials used
throughout their life cycles in various
climatic regions throughout the world.
It is intended that this and related
documents will help achieve the
objective of developing materiel that will
perform adequately under the
environmental conditions likely to be
found throughout its life cycle in the
areas of intended use.
MIL-STD-810 F/G: Part three
Areas of occurrence of climatic design types.
MIL-STD-810 F/G: Part three
Distribution of absolute minimum temperatures
MIL-STD-810 F/G: Part three
Distribution of absolute maximum temperatures
Explosive Atmosphere
Explosive Atmosphere
Explosive Atmosphere test: Purpose
The explosive atmosphere test is performed to:
1.
Demonstrate the ability of materiel to operate in fuel-air explosive atmospheres
without causing ignition
2.
Demonstrate that an explosive or burning reaction occurring within encased
materiel will be contained, and will not propagate outside the test item.
Explosive Atmosphere
Application
This method applies to all materiel designed for use in the vicinity of
fuel-air explosive atmospheres associated with aircraft, automotive,
and marine fuels at or above sea level.
Explosive Atmosphere: Limitations
1. Conservative test
If the test item does not ignite the test fuel-air mixture, there is a low probability that the
materiel will ignite prevailing fuel vapor mixtures in service. Conversely, the ignition of the
test fuel-air mixture by the test item does not mean the materiel will always ignite fuel vapors
that occur in actual use.
2. Altitudes above 16 km
These procedures are not appropriate for test altitudes above approximately 16 km where
the lack of oxygen inhibits ignition.
3. High surface temperatures.
This method is not intended to demonstrate ignition due to high surface temperatures.
Explosive Atmosphere: Effects
Effects of explosive atmosphere environments
Low levels of electrical energy discharge or electrical arcing by devices as simple as
pocket transistor radios can ignite mixtures of fuel vapor and air.
Fuel vapors in confined spaces can be ignited by a low energy discharge such as a
spark from a short-circuited flashlight cell, switch contacts, electrostatic discharge,
etc.
Explosive Atmosphere: Sequence
Sequence among other methods
Considering the approach to conserve test item life by applying what are perceived to
be the least damaging environments first, generally apply the explosive atmosphere
test late in the test sequence.
Vibration, shock, and temperature stresses may distort seals and reduce their
effectiveness, thus making ignition of flammable atmospheres more likely.
Recommend the test item first undergo the above tests (on the same item) to better
approximate the actual operational environment.
Explosive Atmosphere: Procedure Variations
Selecting Procedure Variations.
Before conducting this test, complete the tailoring process by selecting specific
procedure variations (special test conditions/techniques for this procedure) based on
requirements documents, Life Cycle Environmental Profile (LCEP), and information
provided with these procedures.
Fuel
Unless otherwise specified, use n-hexane as the test fuel, either reagent grade or 95 percent nhexane with 5 percent other hexane isomers. This fuel is used because its ignition properties in
flammable atmospheres are equal to or more sensitive than the similar properties of 100/130octane aviation gasoline, JP-4 and JP-8 jet engine fuel. Optimum mixtures of n-hexane and air will
ignite from temperatures as low as 223°C, while optimum JP-4 fuel-air mixtures require a minimum
temperature of 230°C for auto-ignition, and 100/130 octane aviation gasoline and air requires
441°C for hot-spot ignition. Minimum spark energy inputs for ignition of optimum fuel vapor and air
mixtures are essentially the same for n-hexane and for 100/130-octane aviation gasoline. Much
higher spark energy input is required to ignite JP-4 or JP-8 fuel-air mixtures. Use of fuels other
than n-hexane is not recommended.
Explosive Atmosphere: Procedure Variations
Temperature
Heat the fuel-air mixture to the highest ambient air temperature at which the materiel is
required to operate during deployment and provide the greatest probability of ignition.
Altitude simulation
The energy required to ignite a fuel-air mixture increases as pressure decreases. Ignition energy
does not drop significantly for test altitudes below sea level. Therefore, unless otherwise
specified, perform all tests with at least two explosive atmosphere steps, one at the
highest anticipated operating altitude of the materiel (not to exceed 12,200 m (40,000 ft.) where
the possibility of an explosion begins to dissipate), and one between 78 and 107 kPa which is
representative of most ground ambient pressures.
Because of the lack of oxygen at approximately 16 km, do not perform this test at or above this
altitude.
Explosive Atmosphere: Procedure Variations
Fuel-vapor mixture
Use a homogeneous fuel-air mixture in the correct fuel-air ratios for the explosive atmosphere test.
Fuel weight calculated to total 3.8 percent by volume of the test atmosphere represents 1.8
stoichiometric equivalents of n-hexane in air, giving a mixture needing only minimum energy for ignition.
Required information to determine fuel weight:
Chamber air temperature during the test.
Fuel temperature.
Specific gravity of n-hexane
Test altitude: ambient ground or as otherwise identified.
Net volume of the test chamber (L)
Explosive Atmosphere Fuel Calculation
Calculation of the volume of liquid n-hexane fuel for each test altitude:
Explosive Atmosphere: Test Facility
Explosive atmosphere set up data sheet
Chamber volume
160 L
Chamber dimension
Ø 45 cm, depth 70 cm
Chamber temperature
ambient to +80°C
Chamber altitude
up to 20 km (65.617 ft) (55 mBar)
Explosive Atmosphere: Test procedure
Preparation for test
Before starting the test, review pretest information in the test plan to determine test details:
procedures, test item configuration, test temperature and test altitude.
Install the test item in the test chamber in such a manner that it may be operated and controlled
from the exterior of the chamber via sealed cable ports.
Unless permanently sealed (not to be opened for maintenance or other purposes), remove or
loosen the external covers of the test item to facilitate the penetration of the explosive mixture. Test
items requiring connection between two or more units may, because of size limitations, have to be
tested independently. In this case, extend any interconnections through the cable ports.
Operate the test item to determine correct operation.
In all instances, operate the test item in a manner representative of service use.
Explosive Atmosphere: Test procedure
Operation in explosive atmosphere
Step 1. With the test item installed, seal the chamber and stabilize the test item and chamber inner walls
to within 10°C below the high operating temperature of the test item.
Step 2. Adjust the chamber air pressure to simulate the highest operating altitude of the test item (not to
exceed12,200m) plus 2000 meters to allow for introducing, vaporizing, and mixing the fuel with the air.
Step 3. Slowly introduce the required volume of n-hexane into the test chamber.
Step 4. Circulate the test atmosphere and continue to reduce the simulated chamber altitude for at least
three minutes to allow for complete vaporization of fuel and the development of a homogeneous mixture.
Step 5. At a pressure equivalent to 1000m above the test altitude, verify the potential explosiveness of
the fuelair vapor by attempting to ignite a sample of the mixture taken from the test chamber using a
spark-gap device with sufficient energy to ignite a 3.82-percent hexane mixture. If ignition does not occur, purge the
chamber of the fuel vapor and repeat Steps 1-4.
Explosive Atmosphere: Test procedure
Operation in explosive atmosphere
Step 6. Operate the test item and continue operation from this step until completion of Step 7. Make and
break electrical contacts as frequently and reasonably possible.
Step 7. To ensure adequate mixing of the fuel and air, slowly decrease the simulated chamber altitude at
a rate no faster than 100 meters per minute by bleeding air into the chamber.
Step 8. Stop decreasing the altitude at 1000m below the test altitude, perform one last operational check
and switch off power to the test item.
Step 9. Verify the potential explosiveness of the air-vapor mixture as in Step 5 above. If ignition does not
occur, purge the chamber of the fuel vapor, and repeat the test from Step 1.
Step 10. Adjust the simulated chamber altitude to the equivalent of 2000 m above site pressure.
Step 11. Repeat Steps 3-7. At site pressure, perform one last operational check and switch-off power to
the test item.
Step 12. Verify the potential explosiveness of the air-vapor mixture as in Step 5, above. If ignition does not
occur, purge the chamber of the fuel vapor, and repeat the test from Step 10.
Step 13. Document the test results.
Explosive Atmosphere: Test procedure
Operation in Explosive Atmosphere
0 Test Altitude
Explosive Atmosphere test algorithm (only MIL-STD-810 F/G)
Explosive Atmosphere: test results example
Temperature and pressure at test altitudes 30kft to site level
Explosion tests
in the sampling tube
Mechanical tests
Mechanical tests: Vibration
What is vibration:
According to WWW Webster on-line, as of 1997, Main Entry:
vi·bra·tion
Pronunciation: vI-’brA-sh&n. Function: noun.
Date: 1655
1. a periodic motion of the particles of an elastic body or medium in alternately opposite directions from
the position of equilibrium when that equilibrium has been disturbed (as when a stretched cord produces
musical tones or particles of air transmit sounds to the ear)
b : the action of vibrating : the state of being vibrated or in vibratory motion: as
(1) : OSCILLATION (2) : a quivering or trembling motion : QUIVER
2. an instance of vibration
3. vacillation in opinion or action : WAVERING
4. a characteristic emanation, aura, or spirit that infuses or vitalizes someone or something and that can
be instinctively sensed or experienced, often used in plural.
b : a distinctive, usually emotional atmosphere capable of being sensed, usually used in plural
- vi·bra ·tion ·al /-shn&l, -sh& -n&l / adjective
vi·bra·tion·less /-sh&n-l&s/ adjective
Mechanical tests: Vibration
Purpose of Vibration:
Vibration tests are performed to:
1. Develop materiel to function in and withstand the vibration exposures of a life cycle including
synergistic effects of other environmental factors, materiel duty cycle, and maintenance.
2. Verify that materiel will function in and withstand the vibration exposures of a life cycle.
Consumers expect and demand products of high quality and reliability. To fulfill these requirements we
must consider vibration, since at some time in its life the product will be subjected to vibration. Poor
mechanical design will result in mechanical failure and customer dissatisfaction which will add cost and
reduce credibility.
Mechanical tests: Vibration
Mechanical tests: Reasons for Vibration Testing
Some reasons for Vibration Testing
- Reduce product development time
- Ensure new products are fit for purpose
- Reduce in-plant rework due to QA rejection
- Reduce damage in transit and subsequent rejection by the customer
- Reduce marginal or non-performance rejection under Warranty
- Reduce legal costs and damage claims due to incorrect operation of the product
- Maintain a good reputation for the company and its products
- Maintain profit margins
In a highly competitive world marketplace Vibration Testing makes good sense.
Mechanical tests: Sequence among other methods
The accumulated effects of vibration-induced stress may affect materiel performance under other
environmental conditions such as temperature, altitude, humidity, leakage, or electromagnetic
interference (EMI/EMC). When evaluating the cumulative environmental effects of vibration and other
environments, expose a single test item to all environmental conditions, with vibration testing
generally performed first.
If another environment (e.g., temperature cycling) is projected to produce damage that would make the
materiel more susceptible to vibration, perform tests for that environment before vibration tests. For
example, thermal cycles might initiate a fatigue crack that would grow under vibration.
Mechanical tests: Vibration Effects
Effects of vibration environment
Vibration results in dynamic deflections of and within materiel. These dynamic deflections and associated
velocities and accelerations may cause or contribute to structural fatigue and mechanical wear of
structures, assemblies, and parts. In addition, dynamic deflections may result in impacting of elements
and/or disruption of function. Some typical symptoms of vibration-induced problems follow.
1. Chafed wiring.
2. Loose fasteners/components.
3. Intermittent electrical contacts.
4. Electrical shorts.
5. Deformed seals.
6. Failed components.
7. Optical or mechanical misalignment.
8. Cracked and/or broken structures.
9. Migration of particles and failed components.
10. Particles and failed components lodged in circuitry or mechanisms.
11. Excessive electrical noise.
12. Fretting corrosion in bearings.
Mechanical tests: Vibration environment categories
Mechanical tests: Type of Vibration - Sine
Sine Vibration
One of the most common vibration tests is a swept sine test. These tests, as they imply, are a test where
the signal driven into the vibrator is a sine wave and the frequency of the sine wave will change with time
i.e. it will sweep. The level or amplitude of the signal measured on the vibration table can be either
Acceleration, Velocity or Displacement. However, the sensor measuring the vibration is normally an
Accelerometer which produces an output proportional to Acceleration. The controller, however, can
convert the signal from the accelerometer to Velocity (by integration) or Displacement (by double
integration).
Mechanical tests: Type of Vibration - Sine
The units used for sinusoidal vibration testing are:
Frequency
Hz
or
radians/second
Displacement
mm
or
inches
peak - peak or peak
Velocity
m/s
or
in/sec
peak
Acceleration
m/s²
or
gn
peak
Metric Units
Imperial Units
SI Units
D = mm peak - peak
D = in peak - peak
D = mm peak - peak
V = mm/s peak
V = in/s peak
V = mm/s peak
A = gn peak
A = gn peak
A = m/s² peak
F = Hz
F = Hz
F = Hz
G = 9806.65 mm/s²
G = 386.0885827 in/s²
G = 1000 mm/s²
= 3.141592654
= 3.141592654
= 3.141592654
Mechanical tests: Type of Vibration - Sine
There must be hundreds, if not thousands, of swept sine test specifications, but whatever the test, it
should define the following:
1.
The upper and lower frequency of the test,
2.
The level to be maintained at the appropriate frequency,
3.
The rate at which the frequency will sweep and whether it is logarithmic or linear.
4.
The duration of the test or the number of sweeps.
In addition to the option that we have discussed (Sweep Sine), in which sine runs at certain velocity
(sweep rate), there is also an option, where sine will “stand” a certain time in one frequency. This
vibration is called Sine Dwell.
There is also possibility to combine several frequencies in a single experiment, each frequency will be a
certain time.
Because sweep sine "running" at certain frequencies and any moment he is located at certain frequency,
main use is for research - testing the product behavior, search for resonance frequencies (Resonance
Search), and the goals like this.
But there are also cases that sweep sine are used to complete an endurance and resistance tests of the
product.
As we said before, there is also sine dwell. He is used if we want to put load on certain frequencies,
which were found problematic or suspected as those.
Mechanical tests: Type of Vibration - Random
If we observe a structure which has several beams of different length and we excite the structure with a
swept sine test, each beam will vibrate vigorously when excited by its unique resonant frequency.
However, if we excite the same structure with a broad band random signal, we will observe that all the
beams are vibrating vigorously which would tend to indicate that all of the frequencies are present at the
same time. Well they are, and they aren’t. This may seem irrational. However if you consider that over a
short period of time that several frequencies are present, but the quantity and phase of those frequencies
is varying randomly it may make more sense. Time is the key to understanding random. In theory, you
must consider an infinite period of time in order to produce a true spectrum analysis of a random signal.
If the signal is truly random, it will never repeat.
The equipment used to analyze random signals years ago employed electronic bandpass filters to
separate and quantify each frequency. All modern spectrum analyzers now use a mathematical process
known as an FFT (Fast Fourier Transform).
Mechanical tests: Random
As a further explanation of random the following may help. The diagram below shows how sine waves of
different frequencies can be summed to form a complex waveform.
10Hz
20Hz
50Hz
90Hz
Sum
0.1 sec
Mechanical tests: Random
Mechanical tests: Random
Mechanical tests: Random
Figure and Break points for curves Composite two-wheeled trailer vibration exposure.
Mechanical tests: Random
Mechanical tests: Shock
In field simulation tests were examined three general types of mechanical motion and force:
1. Continuous and periodic (like sine vibration)
2. Continuous, but not periodic (like random vibration)
and the last type
3. Not continuous and not periodic
The nearest thing for this is a mechanical shock.
Mechanical tests: Shock
A mechanical or physical shock is a sudden acceleration or deceleration caused, for
example, by impact, drop, kick, earthquake, or explosion. Shock is a transient physical
excitation.
Purpose of Shock test:
Shock tests are performed to:
1. provide a degree of confidence that materiel can physically and functionally withstand the relatively
infrequent, non-repetitive shocks encountered in handling, transportation, and service environments. This
may include an assessment of the overall materiel system integrity for safety purposes in any one or all of
the handling, transportation, and service environments;
2. determine the materiel's fragility level, in order that packaging may be designed to protect the
materiel's physical and functional integrity; and
3. test the strength of devices that attach materiel to platforms that can crash.
Mechanical tests: Shock
Effects of shock.
Mechanical shock has the potential for producing adverse effects on the physical and functional integrity
of all materiel. In general, the level is affected by both the magnitude and the duration of the shock
environment. Durations of shock that correspond with natural frequency periods of the materiel and/or
periods of major frequency components in input shock environment waveforms that correspond with
natural frequency periods of the materiel will magnify the adverse effects on the materiel's overall
physical and functional integrity.
Mechanical tests: Shock
Sequence among other methods.
Sequencing among other methods will depend upon the type of testing, i.e., developmental, qualification,
endurance, etc., and the general availability of test items for test. Normally, schedule shock tests early in
the test sequence, but after any vibration tests.
(1) If the shock environment is deemed particularly severe, and the chances of materiel survival without
major structural or operational failure are small, the shock test should be first in the test sequence. This
provides the opportunity to redesign the materiel to meet the shock requirement before testing to the
more benign environments.
(2) If the shock environment is deemed severe, but the chance of the materiel survival without structural
or functional failure is good, perform the shock test after vibration and thermal tests, allowing the
stressing of the test item prior to shock testing to uncover combined vibration, and temperature failures.
(3) There are often advantages to applying shock tests before climatic tests, provided this sequence
represents realistic service conditions. Test experience has shown that climate-sensitive defects often
show up more clearly after the application of shock environments.
However, internal or external thermal stresses may permanently weaken materiel resistance to vibration
and shock that may go undetected if shock tests are applied before climatic tests.
Mechanical tests: Shock types
Classical shock pulses (mechanical shock machine). Unless the procedure requires the use of a
classical shock pulse, the use of such a pulse is not acceptable unless it can be demonstrated that
measured data is within the tolerances of the classical shock pulses. Only two classical shock pulses are
defined for testing in the method – the terminal peak sawtooth pulse, and the trapezoidal pulse.
Mechanical tests: Shock types - sawtooth pulse
Mechanical tests: Shock types - trapezoidal pulse
Mechanical tests: Test facility - LDS V875 Shaker specification
LDS V875 Electrodynamic Shaker
System vibration force (kN)
System max shock force (kN)
Max acceleration sine peak (gn)
System velocity sine peak (m/s)
Displacement pk-pk (mm)
Payload, max (kg)
35.6
105
110
1.8
50.6
600
Mechanical tests: Test facility – “Closed loop”
Mechanical tests: Test facility – Fixture requirements and design
Mechanical tests: Test facility – Fixture requirements and design
Mechanical tests: Test facility – Fixture requirements and design