Test Requirements Document Model Text

 


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.

  1. Modulation of pulse trains or continuous pulses.

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

  1. Synchronization:

(a) Timing relationships
(b) Reference signal amplitude
(c) Reference signal rise time
(d) Reference signal width

  1. Modulation:
    1. Carrier characteristics

(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.

i.

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.


ii.

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.

iii.

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.

iv.

Spikes, overshoots, noise levels, and d-c levels shall be identified and illustrated.

v.

Waveforms shall include a sync signal reference if applicable.

vi.

Resistance measurements involving semiconductor devices shall include polarity requirements and the current at which the semiconductor impedance was determined.

vii.

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.

viii.

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.

ix.

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.

x.

Input/output test requirements shall be specified at the UUT instead of at interface hardware test points.

xi.

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.

xii.

A single fault shall be assumed when a no-go is encountered.

xii.

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.

xiii.

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.

xiv.

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.

xv.

All test points specified on the detailed test information sheet shall be identifiable on the UUT schematic.

xvi.

If a test point and a connector pin are electrically common, the connector pin shall be used if it is accessible.

xvii.

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.

xviii.

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).

xix.

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.

xx.

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.

xxi.

UUT loads shall be specified in terms of impedance required.

xxii.

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.

xxiii.

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.

xxiv.

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.

xxv.

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.

xxvi.

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.

xxvii.

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.

xxviii.

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.

xxix.

All adjustments that may correct a no-go condition or optimize a critical parameter shall be defined.

xxx.

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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