A Test Requirements Document (TRD) shall define the test performance, test conditions, diagnostic requirements, and support equipment to locate, align, and verify proper operation of an item under test. It will be used in the preparation of test packages, and test procedures for test equipment.
Application: Engineering (developmental), preliminary qualification, qualification, and acceptance testing.
Content
The TRD will be comprised of 4 parts for each item
being tested.
All test parameters and test conditions shall be independent of
any specific test equipment.
1. SCOPE
1.1 Identification.
Note: General requirements shall
be to MIL-STD-1519.
This Test Requirements Document (TRD)
specifies the test requirements contents for the Unit Under Test
(UUT) identified as insert UUT/RU Name, if applicable insert
abbreviation, insert UUT/RU code of the insert title.
Purpose.
State the purpose of the system,
and identify the major functions the UUT/RU performs and describe
the role of the UUT within the system or subsystem of which it
is part.
Introduction.
This Test Requirements Document
has been produced during the System Development Phase, for compliance
with the System Engineering Management Plan (SEMP).
This TRD specifies a set of resources
required to test the preproduction UUT.
After successful completion of the
Formal System Physical Configuration Audit (PCA) this document
will form part of the Production Baseline and subject to change
using the Configuration Management Plan.
This document has been compiled
in the following order.
Section 1 - identifies, states the
purpose and introduces the document
Section 2 - lists the applicable
documents
Section 3 - details the test requirements
and contains or references the appendixes that contain all ATLAS
listings applicable to the UUT.
Insert here any other information
to summarize any other items regarding the purpose and contents
of the document.
APPLICABLE DOCUMENTS
Project Documents.
MIL-STD-1519/1 Test Requirements
Documents, Preparation of
IEEE-Std 416 Abbreviated Test Language
for All Systems
Systems Engineering Management Plan
iaw MIL-STD-499
Identify here by title and identifier
any other project specific documents referenced by this document
and not identified in any higher level documents, e.g., ATLAS
procedure program, Product specifications, PAS, ATP, PTS, etc.
CSCI/HWCI Related Documents/Configuration
Identification Documentation.
Software Product Specification(s)
Hardware Product Specification(s)
General Assembly Drawings, etc.,
Other Documents.
List by title and Identification,
any other documents referenced by this document and not identified
in any higher level documents.
e.g., STANDARDS, SPECIFICATIONS,
DRAWINGS and OTHER PUBLICATIONS.
TEST REQUIREMENTS
The TRD shall provide the information
necessary to test the UUT in the most efficient manner possible
and with a minimum of UUT interface. Sufficient tests shall be
included so that all required performance characteristics can
be verified. A TRD shall be provided for each Replaceable Unit
(RU), RU chassis, and RU subassembly.
The TRD shall provided the information necessary to:
a. Test the performance of the UUT
in accordance with the characteristics described in the detailed
performance characteristics and detect and indicate all faults
and out-of-tolerance conditions.
b. adjust and align the UUT (when applicable).
c. If the UUT is an RU, isolate all
faults to the faulty module or RU chassis (if that contains electrical
components).
d. If the UUT is a reparable RU subassembly
or RU chassis containing electrical components, isolate each fault
to an individual component or to the smallest group of components
consistent with the established maintenance concept. Tests shall
be as simple as possible, independent from each other, and logically
arranged to simplify testing and to eliminate redundancies.
Test sequence.
- Tests shall be arranged such that, after a no-go is encountered
and the replacement action determined, the remaining tests not
influenced by the fault can be conducted.
Types of tests.
The following types of tests shall be documented.
a. Power/stimuli short tests. Power input and stimuli input short checks, to verify that these inputs are not operating into a short circuit, shall be made prior to the application of power or stimuli.
b. Performance tests.
These shall be end-to-end tests that exercise the UUT in various
modes of operation to reveal any degradation in performance characteristics.
Further, any components that are not adequately exercised by the
end-to-end tests shall be verified by an alternative means such
as impedance tests. These tests shall also be designated performance
tests.
c. Diagnostic tests.
Diagnostic tests shall be required to isolate a fault(s) detected
during performance testing, to the specified level.
The following paragraphs contain all
the functional test requirements for the UUT.
Configuration data.
The configuration data shall consist
of the identification of all engineering data applicable to the
UUT. The configuration data format shall be in accordance with
figure 1 and the following:
a. Drawing numbers shall include
the revision used in preparation of the TRD. Unreleased drawings
shall not be accepted.
General data.
The format for the required general
data shall be in accordance with figure 2 and the requirements
specified herein.
UUT design data.
The requirements for the UUT design
data shall be as outlined on sheets 1 and 2 of figure 3 and the
following:
a. Weight: The weight of the UUT shall
be specified within 25 percent of the actual weight.
b. Special tools: (e.g., card extenders,
unusual screwdrivers, etc.)
c. Handling requirements: Any special
handling requirements shall be identified.
d. Unique interface/available equipment:
Any special test conditions or required fixtures shall be defined.
Any pressurization required for bench testing shall be defined.
e. Safety requirements: Special precautions
and instructions regarding personnel and equipment (UUT and test
equipment) protection in the presence of high voltages, r-f radiation,
etc., shall be identified.
f. Power requirements: All UUT input
power source requirements shall be specified, including a-c and
d-c voltages and tolerances, maximum load current, frequency and
tolerance, power supply source impedance, ground returns, and
ripple limits on d-c voltages. When three-phase power is required,
the line-to-line voltages or line-to-neutral voltage shall be
so identified. Maximum allowable line-to-line imbalance and percent
distortion shall be specified.
g. Mating connector data: Identification
of all electrical power mating connectors shall be accomplished
in accordance with sheet 2 of figure 3.
UUT test data.
General procedures and special precautions
that apply to the test procedures as a whole to assure proper
test conditions shall be as outlined on sheet 3 of figure 3.
UUT interface requirements. (adapters)
The characteristics of the equipment
and circuitry required to test the UUT (excluding test equipment)
shall be specified. MIL standard part numbers or component specifications
shall be used to specify electrical/electronic circuits in lieu
of vendor part numbers. Dimensioned drawings shall be included
when the data necessary to design fixtures are not readily available
and apparent on outline and other drawings specified herein. Special
materials required for fixtures (e.g., nonmagnetic materials)
shall be specified. Specification of equipment and circuitry that
requires the use of a specific test device shall be avoided where
possible. Electrical and mechanical interface data shall provide,
as a minimum, a description of the data items specified herein.
The format for UUT interface requirements shall be in accordance
with figure 4.
Electrical interface.
Signal conditioning and connector data
related to the avionics item shall be provided as follows:
a. UUT connector identification: All
UUT connectors and corresponding mating connectors shall be identified.
This shall include the connector manufacturers' nomenclature and
part numbers and a cross reference designation such that all connectors
and pin designations on both the schematics and the drawings may
be determined.
b. Descriptive data shall be provided
on separate sheets that define each signal conditioning circuit.
Descriptive data shall include the following as applicable:
(1) Minimum wire size
(2) Maximum wire size
(3) Wire or coax type
(4) Shielding requirements
(5) Detailed definition of signal conditioning circuits
(6) Grounding requirements
(7) Separation of circuits
(8) Twist pair or twisted multiples requirements
(9) Other
c. Test point connectors: All test
point connectors shall be specifically identified. Information
provided shall include manufacturer's type, and a cross reference
and function designation so that each test point connector and
test point can be located on schematics and other drawings.
Mechanical interface.
a. Mounting, holding, support fixtures:
Descriptive data shall be provided for all mounting, holding,
and support fixtures required for each UUT that cannot be safely
be tested on a flat horizontal work surface.
b. Pneumatic, hydraulic, cooling fixtures:
Descriptive data shall be provided for all fittings, fixtures,
and adapters required to connect pneumatic, hydraulic, and cooling
sources to the UUT.
Detailed performance characteristics.
A detailed description of the performance
characteristics shall be provided for the UUT. As a minimum, the
following information shall be provided:
a. Functional name of the UUT and
vendor's part numbers.
b. Input data: All inputs, electrical,
optical, mechanical, etc., shall be defined and their range and
tolerance specified.
c. Output data: All outputs shall
be specified in terms of their range, accuracy, and relationship
to the input conditions.
d. Test point data: The test points
shall be identified by function, and the signal (input or output)
conditions shall be specified.
e. Controls and ranges of control
(or adjustments)
This data shall describe the item
in sufficient detail that any "black box" with the characteristics
described could be inserted in the system without degrading the
system performance. This data shall also be used by the contractor
in the development of TRD's to assure test consistency at all
levels of maintenance and compatibility between maintenance and
quality assurance test results. Input, output, and test point
data shall be identified by test connector and pin designator,
and by functional name. Functional names shall not be duplicated.
Detailed test information.
Each test to be conducted on a UUT
shall be detailed on a separate test information sheet.
Detailed test information sheet.
The format of the detailed test information
sheet shall be in accordance with figure .
Continuation sheets shall be used when
additional space is required to specify any information. The continuation
sheet shall reference the TRD number, TRD revision, test number,
and the information being continued. The applicable detail test
information sheet shall reference the continuation sheet(s).
Alternatively, test information may
be presented in the form of an atlas test specification for procedural
purposes.
Detailed test data requirements.
Sufficient data shall be provided for
each UUT test to completely describe all input conditions and
measurements required to perform each test. All input, output,
and return connections shall be specified by connector and pin
number or test point at the UUT. Where input conditions are identical
for a series of UUT tests, these conditions may be specified on
the first test and back referenced on each subsequent test. The
requirements herein define the minimum data requirements for each
test of the UUT as applicable. Specific test situations differing
from those described herein shall follow the principles outlined
herein and shall be so specified that the input, output, and test
point conditions are completely defined.
Minimum data requirements for UUT input
conditions.
Power supplies
D-c power supplies.
a. Must specify:
Units:
(1) Nominal voltage Volts
(2) Voltage tolerance +/- Volts or %
(3) Current Amperes
(4) Current tolerance (variance or impedance of UUT load on power
supply in terms of R + JX Ohms. %
(5) Load impedance R + JX Ohms
b. Specify if critical to UUT
Units:
(1) Ripple Volts rms
(2) Noise Volts pk-to-pk
c. Specify load changes if not adequately covered above -
Critical transient response is a typical
example.
A-c power supplies.
a. Must specify:
Units:
(1)Nominal voltage Volts
ac (rms, pk-to-pk. etc.)
(2) Voltage tolerance +/- Volts or %
(3) Nominal frequency Hz
(4) Frequency tolerance Hz or %
(5) Current Amperes
(6) Current tolerance (variance) %
(7) Voltage unbalance Volts or %
(8) Load impedance R + JX Ohms
(9) Current unbalance Amperes/phase
b. Specify if critical to UUT
Units:
Distortion Max %
(1) Phase-to-phase angle (Magnitude and tolerance) Degrees
(2) Phase-to-reference phase (Magnitude and tolerance) Degrees
Signal inputs (analog).
Sinusoidal inputs
to UUT.
a. Must specify:
Units:
(1) Voltage/power magnitude
Volts/watts, db
(2) Voltage/power magnitude tolerance Volts, %, watts, db
(3) Frequency Hz
(4) Load impedance of UUT R + JX Ohms
(5) Offset level Volts
b. Specify if required by UUT
(1) Modulation
(a) Modulation type
(b) Modulation frequency(ies)/rates
(c) Modulation percentage or waveshape
(d) Carrier power/voltage level during modulation on/off ratios
(e) Modulation pulse shapes
(f) Pulse repetition frequency
(g) Swept frequency
(h) Centre frequency
(i) Width of sweep
(j) Sweep rate
(2) Noise levels
(3) Maximum VSWR
(4) Phase angle to reference phase
Pulse input to UUT.
a. Must specify:
Units:
(1) Amplitude Volts
(2) Amplitude tolerance Volts/%
(3) Pulse repetition frequency Hz
(4) Pulse repetition frequency tolerance
Hz or %
(5) Pulse width (50% amplitude) Seconds
(6) Pulse width tolerance Seconds or
%
(7) Pulse rise time (10% to 90%) Seconds
(8) Pulse rise time tolerance +/- Seconds
(9) Pulse fall time (10% to 90%) Seconds
(10) Pulse fall time tolerance +/-
Seconds
(11) Pulse mode Continuous, single
pulse, etc.
(12) Load impedance of UUT R + JX Ohms
(13) Load tolerance: +/- (R + JX) Ohms
(14) Offset from zero Volts
b. Specify if required by UUT
(1) Synchronization characteristics
stating above parameters for reference signal(s) plus timing data
between signals.
NOTE: A timing diagram should be included
if more than two signals must be simultaneously synchronized.
Synchro and resolver input to
UUT.
a. Must specify:
Units:
(1) Three-wire sychro or four-wire
resolver
(2) Frequency Hz
(3) Frequency tolerance Hz or %
(4) Stator voltage Volts
(5) Stator voltage tolerance Volts
or %
(6) Angular output Degrees
(7) Angular output tolerance Degrees
(8) Load impedance of UUT R + JX Ohms
(9) Load unbalance R + JX Ohms
(10) Reference signal
(a) Amplitude Volts
(b) Amplitude tolerance Volts or %
(c) Maximum Current Amperes
Waveform input to UUT (other
than pulses).
a. Must specify:
Units:
(1) Waveshape description of type
(2) Amplitude Volts pk-to-pk
(3) Amplitude tolerance Volts or %
(4) Offset from zero Volts
(5) Offset tolerance Volts
(6) Load impedance of UUT R + JX Ohms
(7) Period and tolerance Seconds
(8) Duration and tolerance Seconds
b. Specify if required by UUT
(a) Timing relationships
(b) Reference signal amplitude
(c) Reference signal rise time
(d) Reference signal width
(3) Symmetry.
Time delayed inputs to UUT.
a. Must specify:
Units:
(1) Delay period Seconds
(2) Delay period tolerance Seconds
(3) Characteristics of time reference signal from UUT
(a) Amplitude
(b) Rise time
(c) Width
(d) Source impedance of UUT
(4) Characteristics of delayed signal
to UUT
(a) Amplitude
(b) Rise time
(c) Width
(d) Load impedance of UUT
Signal inputs (digital).
Serial data inputs to UUT.
a. Logic "0" voltage and
current
b. Logic "1" voltage and
current
NOTE: Current source and sink requirements
shall be stated.
c. Logic "0" voltage tolerance
d. Logic "1" voltage tolerance
e. "0" state load impedance
(R + JX)
f. "1" state load impedance
(R + JX)
g. Bit prf (clock rate)
h. Bit width
i. Bit rise and fall time (min/max)
j. Synchronization requirements - reference
signal from UUT or external
(1) Amplitude
(2) Width
(3) Rise time
(4) Pulse repetition frequency
(5) Source impedance
k. Word length: Total number of bits
l. Pattern of bits expressed in "1"
or "0" format
m. Simultaneity with other serial or
parallel digital inputs.
NOTE: Include timing diagram if more
than 2 simultaneous input channels are required.
Parallel data inputs to UUT.
a. Logic "0" voltage and
current
b. Logic "1" voltage and current
NOTE: Current source and sink requirements shall be stated.
c. Logic "0" voltage tolerance
d. Logic "1" voltage tolerance
e. "0" state load impedance (R + JX)
f. "1" state load impedance (R + JX)
g. Logic format: Return to zero, non-return to zero, etc.
h. Word rate (prf)
i. Bit width
j. Bit rise and fall time (min/max)
k. Number of words in sequence
l. Pattern of bits expressed in "1" or "0"
format
m. Simultaneity with other serial or parallel digital inputs.
NOTE: Include timing diagram if more than 2 simultaneous input
channels are required.
n. Synchronization requirements - reference signal from UUT or
external
(1) Amplitude
(2) Width
(3) Rise time
(4) Pulse repetition frequency
(5) Source impedance
Pressure input to UUT.
a. Must specify:
Units:
(1) Absolute pressure MMHg, PA
(2) Absolute pressure stability
(a) Short term MMHg/MIN, PA/MIN
(b) Long term MMHg/HR, PA/HR
(3) Absolute pressure tolerance MMHg,
PA
(4) Maximum volume of UUT CC, L
(5) Leakage rate CC/MIN
(6) Maximum rate of absolute pressure
change MMHG/MIN, PA/MIN
(7) Range of rate of absolute pressure
change
(8) Absolute pressure rate tolerance
MMHG, PA
(9) Absolute pressure range MMHG, PA
b. Specify if required by UUT
(1) Pressure rate of change MMHG/MIN
Minimum data requirements for UUT
output measurements.
Signal outputs (analog).
D-c voltage from UUT.
a. Must specify:
Units:
(1) Magnitude and polarity +/- Volts
(2) Magnitude tolerance +/- (Volts
or %)
(3) Impedance of UUT signal source
R + JX Ohms
(4) Offset of return from "0" volts Volts
NOTE: For ratios of d-c signals, the
above data shall be provided for each signal plus the nominal
expected value of the ratio and its tolerance.
A-c voltage from UUT (rms)
a. Must specify:
Units:
(1) Frequency of signal Hz
(2) Magnitude Volts rms
(3) Magnitude tolerance +/- (Volts
or %)
(4) Impedance of UUT signal source
R + JX Ohms
(5) D-c offset of return from "0"
volts Volts
NOTE: For ratios of a-c signals or
a-c/d-c signals, the above data shall be provided for each signal
plus the nominal expected value of the ratio and its tolerance.
Phase angle between signals from
UUT.
a. Must specify:
Units:
(1) Frequency Hz
(2) Frequency tolerance +/- (Hz or
%)
(3) Amplitude (2 signals) Volts
(4) Amplitude tolerance +/- (Volts
or %)
(5) Expected angle Degrees
(6) Expected angle tolerance Degrees
(7) Source impedance of UUT (2 signals)
Volts
(8) D-c component(s) Volts.
Frequency of signal from UUT.
a. Must specify:
Units:
(1) Expected frequency Hz
(2) Expected frequency tolerance +/-
(Hz or %)
(3) Amplitude Volts
(4) Amplitude tolerance +/- (Volts
or %)
(5) Impedance of UUT source R + JX
Ohms
NOTES:
(a) For microwave signals, specify waveguide.
(b) For coaxial; so indicate.
(6) Polarity (non-sinusoidal) +/-
(7) Rise time (non-sinusoidal) Seconds
(8) Width (non-sinusoidal) Seconds
(9) D-c offset from "0" volts
Volts
(10) Maximum shunt capacitance, if
other than coaxial connection, that is acceptable pf
Period time of signal(s) from
UUT.
a. Must specify:
Units:
(1) Expected time Seconds
(2) Expected time tolerance Seconds
(3) Amplitude(s) Volts
(4) Amplitude(s) tolerance Volts
(5) Polarity +/-
(6) Impedance of UUT source(s) R +
JX ohms
NOTE: If coaxial, so indicate.
(7) Edge(s) used as reference(s) and
slope(s) Leading or trailing
(8) D-c offset from "0" volts
Volts
(9) Rise time (non-sinusoidal) Seconds
(10) Width (non-sinusoidal) Seconds
(11) Maximum shunt capacitance, if
other than coaxial connection, that is acceptable. pf
Power (average rf) from UUT.
a. Must specify:
Units:
(1) Amplitude Watts
(2) Amplitude tolerance +/- (Watts,
%, dB)
(3) VSWR Ratio
(4) Frequency (normal) Hz
(5) Impedance of UUT source R + JX
ohms
Waveforms from the UUT.
Pulse amplitude measurements.
a. Must specify:
Units:
(1) Expected amplitude Volts pk
(2) Expected amplitude tolerance +/-
(Volts or %)
(3) Frequency (rate) Hz
(4) Frequency (rate) tolerance +/-
Hz
(5) Impedance of UUT source R + JX
ohms
(6) D-c offset from "0" volts
Volts
(7) Polarity +/-
(8) Synchronization signal, if available
- Same data as above for signal to be measured.
NOTE: For pulses containing components
that cross through "0" volts, a sketch of waveform shall
be required for definition.
Pulse rise/fall time measurements.
a. Must specify:
Units:
(1) Expected rise/fall time Seconds
(2) Tolerance Seconds
(3) Slope of measured edge Positive
or negative going Pulse width measurements.
a. Must specify:
Units:
(1) Expected width Seconds
(2) Expected width tolerance Seconds
(3) Measured at 10%, 50% or 90% amplitude
Resistance measurement of UUT.
a. Must specify:
Units:
(1) Expected value ohms
(2) Expected value tolerance ohms
b. Specify if required:
(1) Current flow through unknown Distortion
of signals from UUT.
a. Must specify:
Units:
(1) Waveshape
NOTE: If other than sinusoidal. distortion
criteria shall be defined.
(2) Fundamental frequency Hz
(3) Fundamental frequency tolerance
Hz
(4) Impedance of UUT source R + JX
ohms
(5) Amplitude Volts rms
(6) Amplitude tolerance Volts rms
(7) Expected percent distortion %
(8) Expected percent distortion tolerance
+/- %
Synchro/resolver signals from
UUT.
a. Must specify:
Units:
(1) Identify
(2) Voltage Volts
(3) Voltage tolerance Volts
(4) Frequency Hz
(5) Frequency tolerance Hz
(6) Expected angular position Degrees
(7) Expected angular position tolerance
Degrees
(8) Impedance of UUT source (Line to
Line) R + JX
Pressure output.
a. Must specify:
Units:
(1) Static or differential
(2) Expected value MMHG
(3) Expected value tolerance MMHG
Signal outputs (digital).
Serial signals from UUT.
Logic levels verification.
a. Must specify:
Units:
(1) Logic "0" voltage Volts
(2) Logic "0" voltage tolerance
Volts
(3) Logic "1" voltage Volts
(4) Logic "1" voltage tolerance
Volts
(5) Impedance of UUT source
(a) "0" State R + JX
(b) "1" State R + JX
Bit patterns evaluation.
a. Must specify:
Units:
(1) Bit rates
(2) Bit rise and fall times
(3) Bit width
(4) Logic level
(5) Currents source and sink
(6) * Synchronization requirements
(a) Reference signal
(b) Amplitude
(c) Width
(d) Rise time
(e) Pulse repetition frequency
(f) Source frequency
(7) * Expected bit pattern/word - Expressed
in "1" or "0" format
(8) * Simultaneity with other UUT outputs
NOTE: Include timing diagram if more
than 2 simultaneous input channels are required.
Propagation delay.
a. Must specify:
Units:
(1) Bit/pulse characteristics as in
logic level verification and bit pattern evaluation above.
(2) Expected delay Seconds
(3) Expected delay tolerance Seconds
Parallel signals from UUT.
Logic level verification.
a. Must specify: (Same as required
for serial signal logic level verification.)
Units:
Bit pattern evaluation.
a. Must specify: (Same as required
for serial signal bit pattern evaluation.)
Units:
Propagation delay.
a. Must specify: (Same as required
for serial signal propagation delay.)
Units:
Loads and networks for the UUT.
Electronic elements.
a. Must specify:
Units:
(1) Impedance of load R + JX Ohms
(2) Tolerance on load +/- (R+JX) Ohms
(3) Frequency characteristic, if required
(4) Power rating - average peak Watts/Vars.
(5) Nonlinear characteristic, if required
NOTE: Complex loads shall be specified in standard engineering
units.
Mechanical elements.
a. Must specify as required:
Units
(1) Angular position
(2) Spatial position
(3) Inertia
(4) Torque
(5) Rpm
(6) Pneumatic/hydraulic factors
(7) Other
Loads and networks for the UUT
Electronic elements.
a. Must specify:
Units:
(1) Impedance of load R + JX Ohms
(2) Tolerance on load +/- (R + JX)
Ohms
(3) Frequency characteristic, if required
(4) Power rating - average peak Watts/Vars.
(5) Nonlinear characteristic, if required
NOTE: Complex loads shall be specified
in standard engineering units.
Mechanical elements.
a. Must specify as required:
Units
(1) Angular position
(2) Spatial position
(3) Inertia
(4) Torque
(5) Rpm
(6) Pneumatic/hydraulic factors
(7) Other
Digital patterns.
UUT tests requiring extensive digital
input or output patterns shall be specified on continuation sheets
as outlined on figure . Simultaneous input/output patterns shall
be so noted. Each digital output pattern shall be identified as
a failure or non-failure type pattern. If there is only one acceptable
pattern, the data shall indicate that the tolerance on the pattern
is not applicable. Tolerances related to digital patterns shall
be specified in digital form following the principles stated for
analogue tolerances. Parallel digital patterns shall be related
to the applicable UUT connector pins
Guidelines.
The guide-lines specified herein shall
be followed when preparing detailed test information.
The specification of a-c voltages shall
include a notation of root-mean-square (rms), peak, or peak-to-peak
and shall always include frequency. Percent distortion shall be
included when significant.
Normally, pulse width measurements
shall be specified at the 50 percent amplitude level. When deviation
from this is required, the amplitude levels shall be specified.
Rise and fall times shall be normally
specified between 10 percent and 90 percent levels. When deviation
from this is required, the amplitude levels shall be specified.
Spikes, overshoots, noise levels, and
d-c levels shall be identified and illustrated.
Waveforms shall include a sync signal
reference if applicable.
Resistance measurements involving semiconductor
devices shall include polarity requirements and the current at
which the semiconductor impedance was determined.
Measurements that require longer than
standard measurement delay, for stabilization after input insertion
or other action shall be so noted on the individual test specification
sheets.
If a specific test parameter requires
the measurement of several characteristics, such as rise time,
fall time, and pulse width, and the replacement action for an
out-of-tolerance condition for these characteristics is identical,
then all of the measurements should be specified as one TRD test.
It is recognized that certain component
failure or degradation may not be readily detectable during performance
testing, such as failure of power filters and relay coil noise
suppressers. The TRD shall include tests to ensure that all such
items are checked and failures isolated.
Input/output test requirements shall
be specified at the UUT instead of at interface hardware test
points.
Diagnostic tests shall ignore extremely
remote failure modes e.g., carbon resistors shorting. The failure
modes that are ignored shall be specified in the general test
data section of the TRD.
A single fault shall be assumed when
a no-go is encountered.
Standard engineering terms (ISO), symbols,
abbreviations, and designations shall be used. Special cases not
to be overlooked shall include; the meaning of high and low out-of-tolerance
conditions for a zero volt measurement, and a negative voltage
measurement.
Stimuli that vary in discrete or incremental
steps shall be specified in lieu of continuously variable stimuli
if possible. The steps specified shall be as large as possible.
The addition of external feedback loops
to the UUT to simulate the environment in which the UUT normally
operates shall be avoided and open loop tests made whenever possible.
The external interconnection of elements on the UUT shall be avoided
when these elements can be individually tested.
All test points specified on the detailed
test information sheet shall be identifiable on the UUT schematic.
If a test point and a connector pin
are electrically common, the connector pin shall be used if it
is accessible.
Only the power and stimulus required
to perform a test shall be applied during the test. If adherence
to this requirement will cause an active device on the UUT to
be partially powered, it is permissible to add the power necessary
to fully power the device.
It is understood that some characteristics
of the UUT input signals may not be critical; i.e., any value
within a specified range can be used for test purposes. An allowable
range shall be specified for these non-critical characteristics
instead of a specific value. If an output characteristic is a
function of an input characteristic for which a range is specified,
then the relationship between the input and output characteristics
should be specified. An example of the above would be the test
of a linear amplifier. The input voltage amplitude is a non-critical
characteristic and might be specified as 0-10 volts. The output
voltage, since it is a function of the input voltage, would be
Vout = 5 Vin (assuming an amplification of 5).
Complex output waveforms shall be avoided
whenever possible. The complexity of an output waveform can frequently
be reduced by proper selection of the input signals and still
permit adequate testing of the UUT. A number of simple waveform
tests is preferable to one complex waveform test.
The requirements for electrical interfaces
shall be held to a minimum. As an objective, the electrical interface
shall consist of only a cable that interconnects the UUT and the
test equipment. The use of external circuitry or loads in TRD
tests shall be avoided where possible in order that the above
objective can be met.
UUT loads shall be specified in terms
of impedance required.
When a test requires stimuli with tolerances
of less than one percent, the possibility of using a ratio (output
to input) test shall be considered. If a ratio test could be used,
the additional information necessary to conduct a ratio test shall
be specified in the supplemental data section.
Time or phase - dependent relationships,
if applicable, shall be defined using diagrams as needed. If the
exact value of an input or output is not known, a range shall
be specified.
Individual test requirements such as
signal conditioning, loads and impedance-matching termination's
shall include nominal values, power ratings, voltage standing
wave ratio (VSWR), etc. Complex loads shall be specified in SI
engineering units.
All characteristics of each waveform
shall be included. Some characteristics may not have apparent
relevancy but shall appear in the measured value data selection
of the "Detailed Test Information" sheet; all others,
in the supplemental data section. Each waveform (except sine waves)
shall be described in pictorial illustrations. Nonrepetative waveforms
shall be identified.
Tolerances for every characteristic
shall be specified. The upper and lower tolerance limits shall
be described in the same units as the characteristic. Such terminology
as less than or greater than shall be avoided when significant
high or low limits can be specified. The expressions open circuit
and short circuit may be used if defined.
The output impedance at the test point(s)
with respect to the signal return(s) and the impedance's seen
by the UUT inputs shall be specified for all tests.
Any critical or unusual test requirement
not self evident elsewhere shall be defined. Such requirements
might include susceptibility to noise or transients, time delays
before making measurements, signal and power lead characteristics,
etc.
All adjustments that may correct a
no-go condition or optimize a critical parameter shall be defined.
When more than one component is to
be identified for possible replacement, they should be listed
in their most probable order of failure.
Drawings.
The UUT drawings outlined herein
shall be supplier when specified in the contract.
Outline installation drawings.
Outline drawings shall be in accordance
with the applicable equipment specification.
Unit (main) assembly drawings.
Unit (main) assembly drawings shall
be in accordance with the applicable equipment specification.
Detail and subassembly drawings.
The items specified herein, prepared
in accordance with the requirements of the applicable equipment
specification, shall be provided.
Module/subassembly schematics.
A schematic shall be provided for each
module (including IC's and encapsulated modules) and subassembly.
In lieu of this requirement, the portions of circuitry within
any module or subassembly may be indicated on the unit schematics.
Internal/actual wiring diagrams.
Wiring diagrams shall be provided for
each LRU, module, and subassembly to show the actual physical
wiring arrangement. Wire running lists or tables may be used to
supplement wiring diagrams. Printed circuit layouts showing the
components and modules (symbolically or actual shape) as well
as the printed circuitry shall be included in this requirement.
Printed circuit layouts shall contain sufficient data to permit
any component, module terminal, and junction shown in the schematics
to be located.
Logic diagrams.
Detailed logic diagrams as described
in the standards shall be provided for each UUT in the system,
if applicable. Simple UUT's whose function is readily apparent
from the schematic shall be excluded from this requirement. Items
that are not normally represented by logic diagrams (e.g., Receivers)
shall be depicted by functional block diagrams.
Subassembly drawings.
Subassembly drawings shall be provided
for each module and subassembly. These drawings shall show physical
configuration, connector identification (part number and reference
number) and location, test point location, and identification,
controls, and other features necessary for testing. (In some cases,
this requirement may be satisfied by printed circuit layout drawings.)
Wiring diagrams.
Wiring diagrams will be in accordance
with the applicable equipment specification.
Functional block diagrams.
Functional block diagrams shall
be in accordance with the applicable equipment specification.
Test flow chart.
A test flow chart shall be provided.
The test flow chart shall graphically depict the sequencing and
branching of the TRD performance and diagnostic tests. The chart
presentation shall be in the form of a tree chart.
QUALITY ASSURANCE PROVISIONS
Responsibility for inspection.
Unless otherwise specified in the
contract, the supplier is responsible for the performance of all
inspection/validation requirements as specified herein. Except
as otherwise specified, the supplier may use his own or any other
inspection facilities and services acceptable to the procuring
activity. The procuring activity reserves the right to perform
or witness any of the inspections/validations specified herein.
TRD inspection and acceptance.
All material furnished in accordance
with this specification shall be subject to inspection and acceptance
by the procuring activity.
Inspection.
Inspection shall consist of a review
of the TRD to ensure that the information, instructions, and format
(textual and illustrative) requirements of this specification
are met.
Validation.
Each test in the TRD shall be validated
by the supplier. Validation shall be accomplished by applying
the inputs, loads, etc., specified by the TRD to an acceptable
(a certified good) UUT and verifying that the specified values
are obtained. A validation certificate shall be provided with
each TRD. The validation certificate shall include the following
information:
a. A listing of test numbers, with
the actual values obtained from the measurements made during validation
testing.
b. Complete listing or identification
of:
(1) TRD
(2) UUT
(3) Test equipment
(4) Test personnel
(5) Contract number
(6) Supplier
(7) Sub-supplier (where applicable)
c. Date testing was accomplished:
d. Signature of test personnel
e. Signature of the procuring activity
representative who witnessed or participated in the testing.
Acceptance.
Acceptance of the data required by
this specification shall be accomplished by submittal of copy
of the validated TRD and validation certificate to the procuring
activity. This acceptance, however, is contingent on the final
review of the delivered materials by the procuring activity. The
procuring activity shall notify the TRD supplier of final acceptance
of the data required by this specification.
PREPARATION FOR DELIVERY
The TRD shall be delivered as specified
in the contract and in a format stated in the Contract Data Requirements
List (CDRL).
NOTES
All definitions, abbreviations and
acronyms contained in the SEMP are applicable to this document,
however for convenience a number of them are repeated here.
Include in this section any general information that aids in understanding
this document; a number of paragraphs can be written but as a
minimum the next two shall be included.
Definitions.
Most of these definitions are taken
from the SEMP, if not their source is included.
- Acceptance Test -
Formal test conducted to determine whether or not a system satisfies
its acceptance criteria and to enable the customer to determine
whether or not to accept the system.
- Baseline -
A configuration identification document or a set of such documents
formally designed and fixed at a specific time during a configuration
item's life cycle. Baseline plus approved changes to those baselines,
constitute the current configuration identifications.
- Certification - A
process, which may be incremental, by which a contractor provides
evidence to the contracting agency that a product meets contractual
or otherwise specified requirements.
- Formal Testing -
The process of conducting testing activities and reporting results
in accordance with an approved test plan.
- Unit Under Test -
- include here, in alphabetic order,
any other definition as necessary.
Acronyms and Abbreviations.
CDRL - Contract Data Requirement
List
CSCI - Computer Software Configuration
Item
HWCI - Hardware Configuration Item
LRI/LRU - Line Replaceable Item/Unit
PAS - Product Acceptance Test Specification
PTS - Product Test Schedule
TBD
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