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GB 9254-2008 (GB9254-2008)

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GB 9254-2008: PDF in English
GB 9254-2008
Information technology equipment - Radio disturbance characteristics - Limits and methods of measurement
ICS 33.100
L06
National Standards of People's Republic of China
Replacing GB 9254-1998
IT equipment
Limits and methods of measurement of radio harassment
(CISPR22.2006, IDT)
Published 2008-08-06
2009-09-01 implementation
Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
Standardization Administration of China issued
Table of Contents
Introduction Ⅲ
Introduction Ⅴ
1 Scope 1
2 Normative References 1
3 Definitions 1
4 ITE classification 3
Class 4.1 B ITE 3
4.2 A Class ITE 3
5 conductive power supply terminal and the telecommunication port 3 of disturbance limits
5.1 Power terminal disturbance voltage limit 4
5.2 conducting the telecommunication port common mode disturbance limits 4
6 disturbance limits radiation 4
6.1 1GHz below the limit of 4
More than 6.2 1GHz limit of 5
7 Description of CISPR disturbance limits of 5
Meaning 7.1 CISPR limit of 5
7.2 Application of limits in mass production compliance test 6
6 8 general measurement conditions
8.1 Environmental level 6
General Requirements 6 8.2 pairs arranged EUT
8.3 EUT arrangement 8
8.4 EUT operating state 9
Measurement conducted disturbances and the power supply terminal 109 of the telecommunication port
9.1 Measurement detector 10
9.2 Measurement Receiver 10
9.3 Artificial mains network (AMN) 11
Reference ground plane 11 9.4
9.5 EUT arrangement 11
12 telecommunications measuring 9.6 port harassment
9.7 Measurement Record 14
10 14 radiated disturbance measurements
Measurement detector 14 10.1
10.2 1GHz following measurement receiver 15
10.3 1GHz below the antenna 15
10.4 1GHz following measurement site 15
10.5 1GHz following arrangement of 16 EUT
10.6 1GHz or more measuring radiation emission 16
10.7 Measurement Record 16
Measurement environment of strong signal is present 16 10.8
10.9 measuring the user's site 17
11 17 Measurement Uncertainty
Annex A (normative) alternative test site 25 site attenuation measurements
Annex B (normative) for measuring the peak detector 30 of the Decision Tree
Annex C (normative) common mode measurements may be disposed Test Method and Test 31
Annex D (informative) the impedance stabilization network (ISN) of a circuit example schematic diagram 36
Annex E (informative) signal parameters of the telecommunication port 45
Principles and methods (informative) telecommunication port disturbance measurements Appendix F 47
Some ITE work status of Annex G (informative) 52
Reference 53
Foreword
All technical contents of this standard is mandatory.
Equivalent standards adopted CISPR22.2006 (Version 5.2) "Limits and methods of measurement harassment radio information technology equipment."
This standard CISPR22.2006 standard some editorial errors or wrong to do the following changes.
--- deleted CISPR22. 7 "Abbreviations used in the figure" 2006 (version 5.2) in the table, the original Tables 8 and 9 became the standard
Quasi Table 7 and 8;
In --- 7.2.3 adds dB (μA) units;
8.1 --- second stage, the original 10.5 to 10.8 standard;
8.4 --- last sentence, the original 8.4.1 Appendix to this standard G.1;
--- FIG. 8, FIG. 9 shows a "typical distance" arrow spaced locations has been adjusted;
--- 9.5.1 The last sentence "In case of dispute, the test should be the original tests." Move 9.5.2 "test report" section
After the fall;
--- 10.4.5, delete the original note "AnnexAwilbereplacedbythecorrespondingprocedurewhen
specifiedinCISPR16-1 ".;
--- Table A.1, 600MHz sixth data corresponding to the original "00" to this standard "0.0";
--- FIG A.2b FIG title, the original "vertical polarization" according to standard "horizontal polarization";
FIG C.1 ~ --- FIG C.4, the position of the arrow represent some distance has been adjusted;
C.2 --- line 3, to the description of FIG C.4 C.5 FIG present standard;
--- Figure C.6, the leftmost penultimate block diagram, delete the original "-For" poorly "balancedcable, useISNas
definedin9.6.2c) 4) ";
FIG D.1 ~ --- NOTE D.7 FIG 2, the original text ". 9.6.2c) 1) -4)" to "9.6.2c) 1) -3).";
--- In F.3, the original note in the last sentence "Forlongcableswhereboththevoltageandcurrentlimits
cannotbemet, itisrecommendedtousethepowermeasurementapproachofC.1.5 "deleted.;
--- FIG F.3, the original "Veuctcm" "Zeuctcm" to this standard "Veutcm", "Zeutcm";
Instead of the standard GB 9254-1998 "Limits and methods of measurement of radio disturbance information technology equipment."
Compared with this standard GB 9254-1998, there are major changes.
--- referenced standard version change (see Chapter 2);
--- deleted GB 9254-1998 Table 4 Note 3;
--- increased radiation emission limits 1GHz ~ 6GHz (see 6.2);
--- For the floor device, which distance is changed from the reference ground plane is no greater than 0.15M 0.012m (see 8.3.2);
--- increased work requirements multifunction device state (see 8.4.1);
--- power supply terminal conduction emission test, may be used in addition to continuing 50Ω/50μH artificial network, but also allows the use of
50Ω/50μH 5Ω artificial network (see 9.3);
--- pair (LCL) longitudinal conversion loss parameter values used in the telecommunication test port impedance stabilization network (ISN) has been modified, increased
LCL parameter values for the six types of cable (see 9.6.2)
--- increased (measuring instrument, antenna, space and measurement methods) for the related content 1GHz ~ 6GHz emitted radiation detected
(See 10.6);
--- in the test report, requested uncertainty of measuring instruments and their associated connections (see 10.7 and Chapter 11);
--- conducting emission radiation emitted by the test arrangement has been modified (see FIG. 4 to FIG. 13, etc.);
--- telecommunications increased detection method flowchart (see FIG C.6) port;
--- added some impedance stabilization network diagram (see Appendix D);
--- Added Appendix F;
--- The 1998 version 8.2.1 - 8.2.3 to the new increase in Appendix G. In addition, also provided by the operating state 1998 Edition
The requirements of the wording was changed to the current wording of the recommendation.
This standard Appendix A, Appendix B, Appendix C is a normative, Appendix D, Appendix E, Appendix F., Appendix G is an information appendix.
This standard was proposed by the National Standardization Technical Committee on Radio Interference (SAC/TC79).
This standard by the National Standardization Technical Committee on Radio Interference.
This standard is mainly drafted by. Ministry of Information Industry Institute of Electronics Standardization, Lenovo Group, Huawei Technologies Co., Ltd.
The main drafters. Shi-steel, Chen Li, Lv Feiyan, Zhang Xinghai, Zhang Peng.
This section replaces the following previously issued as follows.
--- GB 9254-1988, GB 9254-1998.
This standard 6.2,9.6.2.c) 1), 10.6 deferred embodiment, i.e., started from the present 18 months after the date of the standard. Figure C.6
"Standard Test Method for selecting a flow chart of" the content from the beginning of the downward path of "power line port" "9.3 using a predetermined method using Table 1 →
Table limits "of the indefinite extension 2 embodiment.
introduction
The present scope of the standard extended to the entire range of radio frequencies 9kHz ~ 400GHz, but only a limited band in the predetermined limit harassment
Value, which limit value is considered to not only protect the radio and telecommunication services, and other devices may be allowed at a predetermined distance required by the reasonable
jobs.
IT equipment
Limits and methods of measurement of radio harassment
1 Scope
This standard applies to 3.1 defined by information technology equipment (ITE).
This standard specifies the level measuring electromagnetic disturbance generated ITE procedure, a predetermined class A and class B limit of disturbance applied to the device
9kHz ~ 400GHz. For yet specified limits of the band, do not measure.
This standard is designed to give uniform requirements for a radio disturbance level of the device within the scope of application, the predetermined limit of disturbance, measurement methods,
Operating conditions and results of treatment.
2 Normative references
Terms of the following documents become provisions of this standard by reference in this standard. For dated reference documents, all later
Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to agreements based on this standard
Whether the latest versions of these documents. For undated references, the latest version applies to this standard.
GB 1002-1996 household and similar purposes plugs and sockets single phase type, basic parameters and dimensions
GB/T 17626.6-2008 Electromagnetic compatibility testing and measurement techniques conducted disturbances induced by radiofrequency fields Immunity (IEC 61000-
4-6.2006, IDT)
GB 4824-2004 industrial, scientific and medical disturbance characteristics (ISM) radio equipment limits and measurement methods (CISPR
11.2003, IDT)
GB 13837-2003 television and sound broadcast receivers and associated disturbance characteristics Limits and methods of a radio apparatus (CISPR13.
2001, MOD)
GB/T 6113.101-2008 radio disturbance and immunity measuring apparatus and methods - Part 1-1. Radio Sao
Disturbance and immunity measuring apparatus measuring equipment (CISPR16-1-1.2006, IDT)
GB/T 6113.102-2008 radio disturbance and immunity measuring apparatus and methods - Part 1-2. Radio Sao
Interference immunity measuring apparatus and ancillary equipment Conducted disturbances (CISPR16-1-2.2006, IDT)
GB/T 6113.104-2008 radio disturbance and immunity measuring apparatus and methods - Part 1-4. Radio Sao
Interference immunity and radiation measuring apparatus harassment aid (CISPR16-1-4.2005, IDT)
GB/T 6113.203-2008 radio disturbance and immunity measuring apparatus and methods - Part 2-3. Radio Sao
Disturbance and immunity measuring method for measuring radiation harassment (CISPR16-2-3.2003, IDT)
GB/T 6113.402-2006 radio disturbance and immunity measuring apparatus and methods - Part 4-2. uncertainty,
Statistics and limit modeling - Uncertainty of measurement equipment and facilities (CISPR16-4-2.2003, IDT)
CISPR16-1-1.2003 radio disturbance and immunity measuring apparatus and methods - Part 1-1. Radio disturbance and immunity test
The amount of equipment measuring equipment
CISPR16-1-4.2007 radio disturbance and immunity measuring apparatus and methods - Part 1-4. Radio disturbance and immunity test
Assisting the amount of radiation harassment
Definition 3
The following definitions apply to this standard.
3.1
IT equipment informationtechnologyequipment
ITE
Any device satisfies the following a) and b) conditions.
a) its main function is able to input, storage of data and telecommunication message, display, retrieval, transmission, processing, switching or control (or several
A combination of functions), the device may configure one or more generally for the terminal port information transfer;
b) rated voltage not exceeding 600V.
For example, a data processing apparatus comprising ITE, office equipment, electronic business equipment, telecommunications equipment.
Any device according to "International Telecommunication Union (ITU) RR", and that the main function is to transmit (or) received (or the ITE
Part) is not within the scope of this standard.
Note. According to the definition of "International Telecommunication Union (ITU) Radio Regulations", with any radio transmitting device and (or) received no function should meet national
Radio regulations, regardless of whether this standard on its effective.
For those devices in the relevant national standards have clearly defined the requirements of all harassment in the band, Van in this standard does not include
Around inside.
3.2
EUT equipmentundertest
EUT
Interacted with on a representative set of ITE ITE or a functional (i.e. system), which comprises one or more host cells, and
It is used to ITE assessed.
3.3
Host cells hostunit
Part, or a unit of ITE ITE system, for accommodating a module. It may contain an RF source, and may provide other ITE
Supply and distribution. Between the module and the host unit, the power distribution mode between the host unit and the other ITE or may be AC, DC, or AC
DC.
3.4
Module module
ITE part, which provide some functionality and may contain a radio frequency source.
3.5
Identical modules and ITE identicalmodulesandITE
Mass production of modules and ITE, its manufacturing tolerances in manufacturing specifications within the specified tolerance range of the nominal.
3.6
Telecommunications/network port telecommunications/networkport
Port voice, data and signaling aimed at by directly connecting the multi-user telecommunications network (e.g., public switched telecommunications network (PSTN),
Integrated Services Digital Network (ISDN), x- Digital Subscriber Line (xDSL), etc.), a local area network (such as Ethernet, token ring, etc.) and the like network,
The dispersed system are interconnected.
NOTE. The port is typically used to connect the various components of the system are connected ITE (e.g., RS-232, IEEEStandard1284 (parallel printer), a universal serial
Bus (USB), IEEE Standard 1394 ( "Firewire"), etc.), if the port in accordance with performance specifications (for example, for a cable connected to its maximum length
In seeking) use, the port is not in the predetermined range defined in the present telecommunications/network port.
3.7
Multifunction devices multifunctionequipment
Information technology equipment having two or more functions specified in the present standard, or other standards in the same unit.
Note. Information technology equipment comprising e.g.
--- providing telecommunications functions and/or broadcast reception function of the personal computer;
--- measurement functions of a personal computer, and so on.
3.8
Total mode impedance totalcommonmodeimpedance
TCM impedance
EUT and the test port connected to the cable impedance between the reference ground plane.
Note. the complete cable may be viewed as a line circuit, while the other is regarded as the ground plane of the antenna circuit. TCM is the transmission wave form of electrical energy, can
Exposed to radiation generated in the electric power cables in an actual use environment. Conversely when the cable is exposed to ambient electromagnetic field, it also plays a major role.
3.9
Arranged arrangement
In the test area, including the peripheral connection/auxiliary equipment, including the physical layout of the EUT.
3.10
Configuration configuration
EUT operation mode and other operating conditions.
3.11
Auxiliary equipment associatedequipment
AE
Auxiliary equipment EUT work. Auxiliary equipment may be placed outside the test regions.
4 ITE classification
ITE divided into A and B types.
Class 4.1 B ITE
Class B ITE refers to a class of devices that meet Class B of disturbance limits.
It is mainly used for domestic environments may include.
--- fixing device is not in place for use, for example, a portable device powered by a built-in battery;
--- a telecommunication network via a telecommunication terminal of the power supply;
--- personal computers and associated auxiliary equipment.
Note. The so-called living environment is the environment that it is possible to use radio and television receivers within 10m far from the scope of the relevant equipment.
4.2 A Class A ITE
It refers to meet Class A ITE-type device that does not meet Class A Class B limit, but the limit values. For this type of device does not limit its sales, but
It shall include the following in its relevant instructions for use.
caveat
This is a Class A product. In a domestic environment, this product may cause radio interference. In this case, the user may be required
To take practical measures against interference.
5 conduction disturbance limits the power supply terminal and the telecommunication port
When using the receiver, respectively, with an average detector and quasi-peak detector, according to the measurement method in Chapter 9, the EUT
Or 3 should satisfy the requirements of Table 1 and Table 2 and Table 4, and the average value of the quasi-peak value. For the telecommunication port shall meet Table 3
Table 4 or claim voltage or current limit value, but measured in accordance with the method C.1.3, should meet the current and voltage limits
Limit requirements. If data with a quasi-peak detector receiver has measured the average value meet requirements shall be considered
EUT while meeting the requirements of the two limits, then the tape does not have to average detector receiver be measured.
If the measurement readings shown on the receiver fluctuating around limit, the observation time less than 15s at each frequency of reading, recording the highest
Reading, isolated instant high value is negligible.
Supply terminal disturbance voltage limits 5.1
Table 1 A conducting terminal of the power level limit of disturbance ITE
Frequency Range/MHz
Limits/dB (μV)
Quasi-peak average value
0.15 ~ 0.50 7966
0.50 ~ 307360
NOTE. In the transition frequency (0.50 MHz) should be used at a lower limit.
Scale power supply terminal 2 B ITE conduction disturbance limits
Frequency Range/MHz
Limits/dB (μV)
Quasi-peak average value
0.15 ~ 0.50 66 ~ 56 56 ~ 46
0.50 ~ 55646
5 ~ 306050
Note 1. In the transition frequency (0.50 MHz and 5MHz) should be used at a lower limit.
Note 2. In the 0.15MHz ~ 0.50MHz frequency range, with the upper limit of the number of the frequency decreases linearly.
5.2 conducting the telecommunication port common mode disturbance limits
Table 3 A common mode level conductive telecommunications interface (asymmetric) disturbance limits
Frequency Range/MHz
Voltage limit/dB (μV) current limit/dB (μA)
Quasi-peak quasi-peak average value of the average
0.15 ~ 0.50 97 ~ 8784 ~ 7453 ~ 4340 ~ 30
0.50 ~ 3087744330
Note 1. In the frequency range of 0.15MHz ~ 0.5MHz, with the upper limit of the number of the frequency decreases linearly.
Note 2. disturbance limits current and voltage are used in the impedance stabilization network under a predetermined impedance (ISN) conditions derived by the impedance stabilization network for
Telecommunications test port 150Ω common mode of presentation (asymmetric) impedance (conversion factor to 20lg150 = 44dB)
Table 4 B conducting the telecommunication port common mode (asymmetric) disturbance limits
Frequency Range/MHz
Voltage limit/dB (μV) current limit/dB (μA)
Quasi-peak quasi-peak average value of the average
0.15 ~ 0.50 84 ~ 74 74 to 64 40 to 30 30 to 20
0.50 ~ 3074643020
Note 1. In the frequency range of 0.15MHz ~ 0.5MHz, with the upper limit of the number of the frequency decreases linearly.
Note 2. disturbance limits current and voltage are used in the impedance stabilization network under a predetermined impedance (ISN) conditions derived by the impedance stabilization network for
Telecommunications test port 150Ω common mode of presentation (asymmetric) impedance (conversion factor to 20lg150 = 44dB)
6 radiation disturbance limits
6.1 1GHz following limits
When measuring method according to clause 10, when measured at a measuring distance R, the EUT should satisfy Table 5 or 6 limits. If the measured
The amount of the receiver shown on the reading fluctuates near the limit, the observation time of the reading of not less than 15s, recording the highest reading, isolated high moment
Value is negligible.
Table 5 A radiation disturbance limits ITE level measured at a distance R (10m) of
Frequency Range/MHz quasi-peak value/dB (μV/m)
30 ~ 23040
230 ~ 100 047
Note 1. In the transition frequency (230MHz) should be used at a lower limit.
Note 2. When interference occurs, allow supplemented by other provisions.
Radiation disturbance limits Table 6 B ITE level measured at a distance R (10m) of
Frequency Range/MHz quasi-peak value/dB (μV/m)
30 to 230 30
230 to 100,037
Note 1. In the transition frequency (230MHz) should be used at a lower limit.
Note 2. When interference occurs, allow supplemented by other provisions.
More than 6.2 1GHz limit
When measured according to the principle of selecting the upper limit frequency measurement method described in Chapter 10 and described below, EUT should satisfy Table 7
Table 8 or limits.
Table 7 A radiation disturbance limits ITE level measured at a distance R (3m) of
Frequency Range/GHz average/dB (μV/m) Peak/dB (μV/m)
1 ~ 35676
3 ~ 66080
Note 1. In the transition frequency (3GHz) should be used at a lower limit.
Table 8 B ITE disturbance limits radiation measured at a distance R (3m) of
Frequency Range/GHz average/dB (μV/m) Peak/dB (μV/m)
1 ~ 35070
3 ~ 65474
Note 1. In the transition frequency (3GHz) should be used at a lower limit.
The upper limit of the frequency measurement selection.
EUT maximum internal source refers to the highest frequency generated or used internally EUT, the EUT or work or tuned frequency.
If the maximum frequency is less than an internal source EUT 108MHz, then the measurement only to 1GHz.
If the internal source of the highest frequency between EUT 108MHz ~ 500MHz, then the measurement only to 2GHz.
If the internal source of the highest frequency between EUT 500MHz ~ 1GHz, then the measurement only to 5GHz.
If the maximum frequency is higher than the internal source EUT 1GHz, then the measurement will proceed to 6GHz or 5 times the highest frequency, whichever
Small ones.
Description 7 pairs of CISPR disturbance limits
Meaning 7.1 CISPR limits
7.1.1 CISPR recommended limit refers to it by the national authorities will limit into national standards, technical regulations and official technology
Surgery normative documents of value. International organizations also recommend the use of these limits.
Limit the meaning specified in 7.1.2 of this standard is. a statistical basis, mass production equipment at least 80% confidence level of not less than 80%
Compliance with the limits.
7.2 Application of limits in the conformance testing of mass production
7.2.1 proceed with the following tests.
7.2.1.1 Methods 7.2.3 statistical evaluation prescribed test for a sample of the model of the device.
7.2.1.2 or for convenience, only one device to be tested.
7.2.2 need to keep the device for subsequent random sampling test during the production process, according to the situation particularly 7.2.1.2.
7.2.3 The following shall be the statistical approach to assess whether the device is compliance with the limits.
The model for the test shall, not less than 5 and not more than the number of samples is 12 samples. If due to the limitation of the actual conditions, not
Five samples can be selected, at this time should be four or three samples of the test sample. Compliance is determined according to the following formula.
x kSn≤L
S2n = 1n-1Σ
(Xn-x) 2
Where.
--- X number of samples in the sample arithmetic average of the measured values of the n-time;
--- Xn single sample measurement;
L --- respective limit of disturbance;
K --- T derived from the non-central distribution coefficient table. It means that the type of sample 80% confidence level of not less than 80%
In the limit L or less. k depends on the value of the sample space n, the table below.
n 3 4 5 6 7 8 9 10 11 12
k 2.04 1.69 1.52 1.42 1.35 1.30 1.27 1.24 1.21 1.20
xn, x, Sn and L expressed by the following logarithmic unit. dB (μV), dB (μA), dB (μV/m) or dB (pW).
7.2.4 When the measurement result of objections, only the samples tested using the method in accordance with statistical evaluation 7.2.1.1, only
To consider whether to ban its sale and cancel its "type approval."
8 general measurement conditions
8.1 ambient level
The test area shall be done to distinguish between harassment and ambient noise from the EUT. Site applicability in this regard, by measuring ring
Ambient noise level (EUT does not work) to be determined. should ensure that at least the low noise level than required by Chapter 5 and Chapter 6 limits 6dB.
If less than 6dB in a low frequency band, the ambient noise level than the prescribed limits, then the method can be used to give the point of view EUT 10.8
Meets the requirements prescribed limits.
The results of both the synthesis and environmental noise sources harassment does not exceed a predetermined limit value, the ambient noise level is not necessarily required than a predetermined limit
Low 6dB. In this case, the source may be considered to meet a predetermined emission limits; and when both the environmental noise and harassing sources engagement
As a result exceeds a predetermined limit value, the EUT can not meet the requirements determined limit, unless each frequency exceeds a corresponding limit value
Indicate points can simultaneously satisfy the following two conditions.
a) at least ambient noise level than the source harassment plus 6dB low ambient noise level;
b) at least ambient noise level is 4.8dB lower than a predetermined limit.
General Requirements 8.2 pairs arranged EUT
Unless otherwise specified, EUT configuration, installation, and operation of the arrangement should be consistent with typical applications. Should interface cable, or load
At least one port means connected to the EUT in each type of interface ports. If possible, it should be the practical application of devices
Typically each cable termination.
If a plurality of interfaces of the same type is present, based on the results of the pre-test, it may be necessary to add EUT interconnecting cables, or the load means
Home. As long as EUT still meet the requirements, increase the number of cables of the same type should be subject to the following conditions. add the cable is not obvious
Effect size transmission level, i.e. varies less than 2dB. Why choose to configure and load the relevant port should be specified in the test report.
Interconnect cables comply with the specific device type and length specified in the claims. If the length specified is variable, should be used will
Produce maximum emission.
If a shielded cable or special limits during testing to meet the requirements, should be used in this specification indicate the use of
Species recommended cable.
Long part of the cable to be bundled in the vicinity of the center of the cable after being folded, folding a length of 0.3m ~ 0.4m. If for cable
Too large or difficult to bend, or due to be tested at the installation site and the user can not do so, it should indicate to accurately in the test report
Cable processing portion made long.
If there are multiple devices of the same type of interface ports, if they can prove that the cable does not add significantly affect the test results, only then will a
Cables to the ports of such a port can be.
Any set of test results must be accompanied by a complete description of the cable and equipment orientation so that the test results are reproducible. Such as
If the request requires limits in order to meet specific conditions of use, such as cable lengths, cable type, shielding and grounding, these conditions must be
Provided to the user specified in the instructions for use.
Typical applications for the device should usually have a plurality of modules (drawer units, cards, floor, etc.) in the case where the number of modules and a feed composition
Line test. EUT still met as long as the requirements, the same type of circuit board or card number according to the following conditions. add circuit
The board or card does not significantly affect the magnitude of the transmission level, i.e. varies less than 2dB. Select the module number and type of justification should be in the test report
As noted.
System consists of several independent units shall be minimum, a representative configuration combinations. Number of test set contained unit
And compositions that generally should be representative of a typical system configuration used. Select units reasons should be stated in the test report.
Minimum, a representative configuration example as follows.
For personal computers or computer peripheral devices, the minimum configuration consists of the following units, as a whole experiment was carried out.
a) a personal computer;
b) a keyboard;
c) video display unit;
d) for two different types of available I/O protocol (e.g., parallel, serial, etc.) with external peripheral device;
e) If there EUT for specific devices (such as a mouse or joystick) with dedicated port, the device connected to the port should be considered
As part of the minimum configuration.
Note. In some systems, a), b) and/or c) may be assembled in a chassis. But in any case, a), b), c), a mouse or joystick can not
Alternatively d).
For sale terminal, the minimum system means composed of the following (to the extent of operation), and tested as a whole.
a) a processor (drawer unit);
b) cash drawer;
c) keyboard;
d) a display unit (for operators and consumers use);
e) Typical peripheral devices (bar code scanners);
f) the handheld device (bar code scanner).
In each EUT in ITE to be evaluated, is to give each type of module has an in working condition, and for system
For EUT, the EUT should be included for each type of system configuration may contain one each ITE.
For those wide distribution, both become part of the system (such as a data processing terminal or a workstation, or a non-public telecommunications branch
Switch, etc.), but also from the equipment unit-component system, it can be independently of the host unit or system tested separately. In the trial by
Cable length and the actual loa...
......