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Trialon
Corporation is a world leader when it comes to testing products
to MIL-STD-202. With the commitment “to do what ever it takes”
is why we are one of the largest independent engineering and testing
organizations in North America. We have several technicians with
over fifteen years of experience in testing products to Environmental
Simulation, Vibration, Mechanical Shock, EMC, and Electrical tests.
Whether your product is Air, Land, Sea, or Space, the staff at Trialon
Corporation are committed to provide the best testing services “On
Time, Every Time.”
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This standard
establishes uniform methods for testing electronic and electrical
component parts, including basic environmental tests to determine
resistance to deleterious effects of natural elements and conditions
surrounding military operations, and physical and electrical tests.
For the purpose of this standard, the term "component parts"
includes such items as capacitors, resistors, switches, relays,
transformers, and jacks. |
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This standard
is intended to apply only to small parts such as transformers and
inductors, weighing up to 300 pounds or having a root mean square
test voltage up to 50,000 volts unless otherwise specifically invoked.
The test methods described herein have been prepared to serve several
purposes: |
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To
specifiy suitable conditions obtainable in the laboratory
which give test results equivalent to the actual service
conditions existing in the field, and to obtain reproducibility
of the results of tests. The tests described herein are
not to be interpreted as an exact and conclusive representation
of actual service operation in any one geographic location,
since it is known that the only true test for operation
in a specific location is an actual service test at that
point.
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- To describe
in one standard (1) all of the test methods of a similar character
which appeared in the various joint or single-service electronic
and electrical component parts specifications, (2) those test
methods which are feasible for use in several specifications,
and (3), the recognized extreme environments, particularly temperatures,
barometric pressures, etc., at which component parts will be
tested under some of the presently standardized testing procedures.
By so consolidating, these methods may be kept uniform and thus
result in conservation of equipment, man-hours, and testing
facilities. In achieving these objectives, it is necessary to
make each of the general tests adaptable to a broad range of
electronic and electrical component parts.
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- The test methods
described herein for environmental, physical, and electrical
tests shall also apply, when applicable, to parts not covered
by an approved military specification, military sheet form standard,
specification sheet, or drawing.
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Source:
MIL-STD-202 Test Method Standard, Electronic and Electrical Component
Parts (with Notice 1 Incorporated) |
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Trialon
Corporation is able to test to the following Test Methods under
MIL-STD-202: |
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Method
101 Salt Fog Testing |
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Method
211 Terminal Strength Testing |
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The
salt-spray test, in which specimens are subjected to a fine mist
of salt solution, has several useful purposes when utilized with
full recognition of its deficiencies and limitations. Originally
proposed as an accelerated laboratory corrosion test simulating
the effects of seacoast atmospheres on metals, with or without protective
coatings, this test has been erroneously considered by many as an
all-purpose accelerated corrosion test, which if "withstood
successfully" will guarantee that metals or protective coatings
will prove satisfactory under any corrosive condition. |
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This
test is performed to determine whether the design of the terminals
and their method of attachment can withstand one or more of the
applicable mechanical stresses to which they will be subjected
during installation or disassembly in equipment. These stresses
must be withstood by the component part without sustaining damage
which would affect either the utility of the terminals or the
operation of the component part itself.
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Method
103 Humidity Testing |
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Method
213 Mechanical Shock Testing |
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This test
is performed to evaluate the properties of materials used in components
as they are influenced by the absorption and diffusion of moisture
and moisture vapor. This is an accelerated environmental test, accomplished
by the continuous exposure of the specimen to high relative humidity
at an elevated temperature. |
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This test
is conducted for the purpose of determining the suitability of component
parts and subassemblies of electrical and electronic components
when subjected to shocks such as those which may be expected as
a result of rough handling, transportation and military operations.
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Method
104 Immersion Testing |
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Method
214 Random Vibration Testing |
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This test
is performed to determine the effectiveness of the seal of component
parts. The immersion of the part under evaluation into liquid at
widely different temperatures subjects it to thermal and mechanical
stresses which will readily detect a defective terminal assembly,
or a partially closed seam or molded enclosure. Defects of these
types can result from faulty construction or from mechanical damage
such as might be produced during physical or environmental tests.
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This test
is conducted for the purpose of determining the ability of component
parts to withstand the dynamic stress exerted by random vibration
applied between upper and lower frequency limits to simulate the
vibration experienced in various service field environments. Random
vibration is characteristic of modern field environments produced
by missiles, high-thrust jets and rocket engines. In these types
of environments, the random vibration provides a more realistic
test. |
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Method
105 Barometric Pressure Testing |
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Method
215 Resistance to Solvents |
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The barometric
pressure test is performed under conditions simulating the low atmospheric
pressure encountered in the non-pressurized portions of aircraft
and other vehicles in high altitude flight. This test is intended
primarily to determine the ability of component parts and materials
to avoid dielectric-withstanding-voltage failures due to the lowered
insulating strength of air and other insulating materials at reduced
pressures. Even when low pressures do not produce complete electrical
breakdown, corona and its undesirable effects, including losses
and ionization, are intensified. Low barometric pressures also serve
to decrease the life of electrical contacts, since intensity of
arcing is increased under these circumstances. |
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To verify
that markings or color coding will not become illegible or discolored
on the parts (including printed wiring boards) when subjected to
solvents and processes normally used to clean solder-flux, fingerprints,
and other contaminants from printed-wiring and terminal-board assemblies.
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Method
106 Moisture Resistance Testing |
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Method
301 Dielectric withstanding voltage |
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The moisture
resistance test is performed for the purpose of evaluating, in an
accelerated manner, the resistance of component parts and constituent
materials to the deteriorative effects of the high-humidity and
heat conditions typical of tropical environments. Most tropical
degradation results directly or indirectly from absorption of moisture
vapor and films by vulnerable insulating materials, and from surface
wetting of metals and insulation.
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The dielectric
withstanding voltage test (also called high-potential, over potential,
voltage breakdown,or dielectric-strength test) consists of the application
of a voltage higher than rated voltage for a specific time between
mutually insulated portions of a component part or between insulated
portions and ground. This is used to prove that the component part
can operate safely at its rated voltage and withstand momentary
over potentials due to switching, surges, and other similar phenomena. |
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Method
107 Thermal Shock Testing |
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Method
302 Insulation Resistance |
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This test
is conducted for the purpose of determining the resistance of a
part to exposures at extremes of high and low temperatures, and
to the shock of alternate exposures to these extremes, such as would
be experienced when equipment or parts are transferred to and from
heated shelters in arctic areas. |
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This test
is to measure the resistance offered by the insulating members of
a component part to an impressed direct voltage tending to produce
a leakage of current through or on the surface of these members
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Method
108 Life Testing |
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Method
303 DC Resistance |
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This test
is conducted for the purpose of determining the effects on electrical
and mechanical characteristics of a part, resulting from exposure
of the part to an elevated ambient temperature for a specified length
of time, while the part is performing its operational function.
This test method is not intended for testing parts whose life is
expressed in the number of operations. |
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This test
is to measure the direct-current (dc) resistance of resistors, electromagnetic
windings of components, and conductors.
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Method
201 Vibration Testing |
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Method
304 Resistance-Temperature Characteristic |
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The vibration
test is used to determine the effects on component parts of vibration
within the predominant frequency ranges and magnitudes that may
be encountered during field service. Most vibration encountered
in field service is not of a simple harmonic nature, but tests based
on vibrations of this type have proved satisfactory for determining
critical frequencies, modes of vibration and other data necessary
for planning protective steps against the effects of undue vibration.
Vibration, by causing loosening of parts or relative motion between
parts in the specimen, can produce objectionable operating characteristics,
noise, wear, and physical distortion, and often results in fatigue
and failure of mechanical parts. |
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It is the
purpose of this test to determine the percentage change in direct-current
(dc) ohmic resistance from the dc ohmic resistance at the reference
temperature, per unit temperature difference between the test temperature
and the reference temperature.
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Method
204 High Frequency Vibration Testing |
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Method
304 Capacitance |
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The high
frequency vibration test is performed for the purpose of determining
the effect on component parts of vibration in the frequency ranges
of 10 to 500 hertz (Hz), 10 to 2,000 Hz or 10 to 3,000 Hz, as may
be encountered in aircraft, missiles, and tanks. |
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The purpose
of this test is to measure the capacitance of component parts.
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Method
208 Solderability Testing |
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Method
304 Contact Resistance |
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The purpose
of this test method is to determine the solderability of all terminations,
which are normally joined by a soldering operation. This determination
is made on the basis of the ability of these terminations to be
wetted by solder and the predictability of a suitable fillet resulting
from solder application.
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The purpose
of the contact resistance test is to determine the resistance offered
to a flow of current during its passage between the electrical contacting
surfaces of connecting components, such as plugs, jacks, connectors,
and sockets, or between the electrical contacts of current controlling
components, such as switches, relays, and circuit breakers. |
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Method
210 Resistance to Solder Heat Testing |
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This test
is performed to determine whether wire and other component parts
can withstand the effects of the heat to which they will be subjected
during the soldering process (solder iron, solder dip, solder wave,
or solder reflow). |
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