GB/T 19951-2019 PDF in English
GB/T 19951-2019 (GB/T19951-2019, GBT 19951-2019, GBT19951-2019)
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Road vehicles -- Disturbances test methods for electrical/electronic component from electrostatic discharge
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GB/T 19951-2019: PDF in English (GBT 19951-2019) GB/T 19951-2019
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 43.040.10
T 36
Replacing GB/T 19951-2005
Road vehicles - Disturbances test methods for
electrical/electronic component from electrostatic
discharge
(ISO 10605:2008, Road vehicles - Test methods for electrical disturbances
from electrostatic discharge, MOD)
ISSUED ON: JUNE 04, 2019
IMPLEMENTED ON: JANUARY 01, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3
1 Scope ... 6
2 Normative references ... 6
3 Terms and definitions ... 6
4 Test conditions ... 7
5 Test location ... 7
6 Test apparatus and instrumentation ... 8
7 Discharge modes ... 12
8 Component test method (DUT powered-up) ... 13
9 Component test method (DUT unpowered) ... 18
10 Vehicle test method ... 21
11 Test report ... 24
Annex A (Normative) Verification of ESD generator ... 25
Annex B (Informative) Guidelines for current target design ... 29
Annex C (Informative) Function performance status classification (FPSC) and
example severity levels ... 42
Annex D (Informative) Selection guidance for test method of component
discharge ... 45
Annex E (Informative) Optional test set-up and procedure for components
(powered-up test) ... 48
Foreword
This Standard is drafted in accordance with the rules given in GB/T 1.1-2009.
This Standard replaces GB/T 19951-2005. The main differences between this
Standard and GB/T 19951-2005 are as follows:
- Adjust the terms (see Clause 3; Clause 3 of the 2005 edition);
- ADD test conditions, test location, and discharge modes (see Clauses 4, 5,
and 7);
- There are major modifications to the provisions on test apparatus and
instrumentation (output voltage, discharge resistance, and reduction of
apparatus variety specified) (see Clause 6; Clause 4 of the 2005 edition);
- MAKE major adjustments to the test methods, including component
powered-up test method and vehicle test method (see Clauses 8 and 10;
Clauses 5 and 6 of the 2005 edition);
- Adjust the requirements for evaluation of test results and test report (see
Clauses 8, 9, and 11; Clauses 5~7 of the 2005 edition);
- ADD “Guidelines for current target design”, “Selection guidance for test
method of component discharge”, and “Optional test set-up and procedure
for components (powered-up test)”, to specify the calibration, test methods,
and test procedure of the device (see Annexes B, D, and E);
- CHANGE the function performance status classification to an informative
annex (see Annex C; Annex B of the 2005 edition).
This Standard uses the redraft law to modify and adopt ISO 10605:2008 “Road
vehicles - Test methods for electrical disturbances from electrostatic discharge”.
The structural adjustment of this Standard compared with ISO 10605:2008 is
as follows:
- No subclauses under 6.3;
- No subclauses under 9.3.3;
- ADD 9.3.7;
- Delete C.3 and C.4;
- The content of Annex F of the source text is adjusted to Annex E.
There are technical differences between this Standard and ISO 10605:2008.
The clauses involved in these differences have been marked by a vertical single
line (|) at the blank of the outer margin.
The technical differences between this Standard and ISO 10605:2008 and their
reasons are as follows:
- About normative references, this Standard has made adjustments with
technical differences, to adapt to the technical conditions of China. The
adjustments are reflected in Clause 2 “Normative references”, as follows:
Delete ISO 7637-1 and ISO 11452-1;
ADD a reference to GB/T 29259-2012.
- GB/T 29259-2012 has included the terms of electrostatic discharge, human
ESD model, reference plane, and electrostatic discharge simulator
(generator), so delete the 3.5, 3.6, 3.7, and 3.10 contents of the source text.
- In order to clearly describe the contact discharge current waveform, and to
facilitate understanding of the meanings of t1 and t2 in Table 2, with
reference to the relevant standard, below Table 2, ADD Figure 3 “Schematic
diagram for contact discharge mode waveform parameters”. The
subsequent figure numbers change in order.
- ADD the functional requirements after component test, as post-test result
judgement, see 9.3.7.
- The 6.3.2 content of the source text is unnecessary statement, and is easy
to cause misunderstanding, so it is deleted.
This Standard makes the following editorial changes:
- Modify the standard name;
- INCORPORATE the amendments of ISO 10605:2008/Amd 1:2014 and ISO
10605:2008/Cor. 1:2010. The clauses involved in these amendments have
been marked by a vertical double line (ǁ) at the blank of the outer margin;
- For ease of understanding, GIVE a note to the current/test voltage (A/kV)
in Table 2;
- The description of test voltage in 8.4.5 of the source text is the same as that
in 8.3.6. This Standard does not repeat the description but refers to 8.3.6
instead. 9.3.3, 9.3.4, 9.3.5, 9.3.6, 10.3.3 are all treated in this way;
- Delete the comment for “1” in Figure B.1c) “Cut side view” in Annex B of the
source text and change “1” to “M3 screw hole”;
- In order to maintain the unification of expression and understanding of
function performance status classification (FPSC) between several
standards of electromagnetic immunity series, the content of function
performance status classification (FPSC) of Annex C is directly referred to
GB/T 33014.1;
- The source text’s Annex E “Rationale for air discharge generator verification”
is not directly related to the technical requirements and test methods of the
standard, and the drafting is extremely non-standard and so deleted.
This Standard was proposed by Ministry of Industry and Information Technology
of the PRC.
This Standard shall be under the jurisdiction of National Technical Committee
of Auto Standardization (SAC/TC 114).
Responsible drafting organizations of this Standard: China Automotive
Technology and Research Center Co., Ltd., Suzhou 3C-Test Electronic Co., Ltd.,
China Electronics Standardization Institute, Changchun Automotive Test Center
Co., Ltd., Shanghai Volkswagen Co., Ltd., Xiangfan Da An Automobile Test
Center, Shanghai Electrical Apparatus Research Institute, Yanfeng Visteon
Electronics Technology (Shanghai) Co., Ltd., SAIC GM Wuling Automobile Co.,
Ltd., Zhengzhou Yutong Bus Co., Ltd., SAIC Motor Passenger Vehicle
Company, SAIC Motor Commercial Vehicle Technical Center, Brilliance Auto
Group Holdings Co., Ltd., Pan Asia Technical Automotive Center Co., Ltd.,
Centre Testing International Group Co., Ltd., Anhui Jianghuai Automobile Group
Corp., Ltd., Shenzhen Hangsheng Electronics Co., Ltd., FAW-Volkswagen
Automotive Co., Ltd., Chery Automobile Co., Ltd., Guangqi Honda Automobile
Co., Ltd., Great Wall Motor Co., Ltd., Guangzhou GRG Metrology & Test Co.,
Ltd.
Participating drafting organizations of this Standard: Bosch Automotive
Products (Suzhou) Co., Ltd., Toyota Motor Technical Center (China) Co., Ltd.,
BMW (China) Services Ltd., Mercedes-Benz (China) Automobile Sales Co., Ltd.,
Volkswagen (China) Investment Co., Ltd., Ford Motor (China) Co., Ltd., Jaguar
Land Rover China, Daimler Greater China Ltd., Peugeot Citroen (Shanghai)
Management Co., Ltd.
Main drafters of this Standard: Xu Xiuxiang, Hu Xiaojun, Cui Qiang, Liu Xin, Lin
Yanping, Liu Xinliang, Liu Ketao, Liu Yuan, Cui Weidong, Deng Fuqi, Lu
Changjun, Wu Dingchao, Cao Shanggui, Zou Aihua, Chu Yangang, Li Zheng,
Liu Yingli.
Road vehicles - Disturbances test methods for
electrical/electronic component from electrostatic
discharge
1 Scope
This Standard specifies the test methods for the tolerance of vehicle’s
electrical/electronic components against electrostatic discharge (ESD), which
may be caused by assembly, service, and occupants inside and outside the
vehicle, including component and vehicle level tests.
This Standard applies to electrical/electronic components for type M, N, O, L
vehicles (unlimited vehicle power systems, such as spark ignition engines,
diesel engines, motors).
2 Normative references
The following documents are indispensable for the application of this document.
For the dated references, only the editions with the dates indicated are
applicable to this document. For the undated references, the latest edition
(including all the amendments) are applicable to this document.
GB/T 29259-2012 Road vehicle - Electromagnetic compatibility terminology
3 Terms and definitions
The terms and definitions defined in GB/T 29259-2012 and the following apply
to this document.
3.1 Device under test; DUT
Single component or combination of components as defined to be tested.
3.2 Air discharge
Test method characterized by bringing the test generator charging electrode
close to the device under test (DUT); the discharge is by arcing on the DUT.
3.3 Contact discharge
Test method characterized by contact of the test generator electrode with the
DUT, where discharge is initiated by the generator discharge switch.
3.4 Direct discharge
Test method for discharging directly on the DUT.
3.5 Indirect discharge
Test method for discharging on a coupling plane near the DUT. It is generally
used to simulate discharge by a human being on items near the DUT.
3.6 Surface
Uninterrupted housing area, gap or opening of DUT, such as tip switches, points
of contact, air vents, speaker openings.
3.7 Holding time
Interval of time within which the decrease of the test voltage due to leakage,
prior to the discharge, is 10 %.
3.8 Horizontal coupling plane; HCP
Metal plane oriented in horizontal direction, to which discharges are applied to
simulate discharge to objects adjacent to the DUT.
4 Test conditions
The environmental conditions during the test are as follows. When other test
conditions are used, they shall be recorded in the test report:
- Ambient temperature: (25 ± 10) °C;
- Relative humidity between 20 % and 60 % (20 °C and 30 % relative humidity
preferred).
The user shall specify the test level, see Annex C.
5 Test location
It shall be carried out in a laboratory which meets environmental conditions.
Special locations, such as a shielded room or an anechoic chamber, may be
used.
Note: ESD testing creates transient fields, which can interfere with sensitive electronic
devices or receivers, even at a distance of a few meters. It is advisable that this be
considered when choosing a test location.
6 Test apparatus and instrumentation
6.1 ESD generator
The ESD generator should be able to generate a repetition rate of at least 10
discharges per second. Regardless of automatic or manual control, any
degradation of the discharge current waveform shall not occur. In cases where
a 2 m length of the discharge return cable is insufficient (e.g. for tall DUTs), a
length not exceeding 3 m may be used and compliance with the waveform
specifications shall be guaranteed. The characteristic parameters of the ESD
generator are shown in Table 1.
Note: When an ESD generator is supplied from an external supply source or controlled by
a separate unit, this/these cable(s) is/are not combined (bundled) with the ESD
generator discharge return cable, to avoid unintended current flowing through
this/these cable(s).
Table 1 -- Characteristic parameters of ESD generator
6.2 Discharge electrodes
6.2.1 Contact discharge electrode
The electrode for contact discharge is typically made of stainless steel, as
shown in Figure 1.
Dimensions in millimeters
Key:
1 - Sharp point.
Figure 1 -- Contact discharge mode electrode of the ESD generator
6.2.2 Air discharge electrode
The electrode for air discharge is shown in Figure 2. For air discharge at test
voltages higher than 15 kV, larger electrode tip (e.g. 20 mm to 30 mm diameter)
can be used to avoid pre-discharge.
Dimensions in millimeters
Key:
1 - Body of ESD generator.
Figure 2 -- Air discharge mode electrode of the ESD generator
6.3 Contact discharge mode current verification
The contact discharge mode currents shall be verified according to Annex A.
The contact discharge mode waveform parameters shall be in accordance with
Table 2. Examples of calculated contact discharge waveforms in accordance
with Table 2 are given in Figures 4a) and b).
Table 2 -- Contact discharge mode waveform parameters
Figure 3 -- Schematic diagram for contact discharge mode waveform
parameters
Note 1: The peak current is obtained from actual measurement.
Note 2: t1 and t2 are the two times of the falling edge of current pulse. t1=R×C(1-40%); t2=R×C(1+20%); as shown in
Figure 3. It is used to determine whether the current pulse amplitude corresponding to t1 and t2 meets the
requirements of GB/T 17626.2.
Note 3: The current/test voltage (A/kV) is a scaling factor. The current at different test voltages is multiplied by the
scaling factor.
Ipeak
I at t1
I at t2
Key:
X - Time, ns;
Y - Current, A;
1 - 330 pF/330 Ω;
2 - 150 pF/330 Ω.
a) 150 pF/330 pF, 330 Ω
Figure 4 -- Examples of calculated contact discharge waveform (5 kV
test voltage)
Key:
X - Time ,ns;
Y - Current, A;
1 - 330 pF/2 kΩ;
2 - 150 pF/2 kΩ.
b) 150 pF/330 pF, 2 kΩ
Figure 4 (continued)
6.4 Horizontal coupling plane and ground/reference plane
The horizontal coupling plane (HCP) and ground/reference plane (GRP) shall
be metallic sheets (e.g. copper, brass or aluminium) and a minimum thickness
of 0.25 mm. If aluminium is used, care is taken that oxidation does not prevent
a good ground connection. GRP is placed under the non-conductive table.
The HCP shall extend the projected geometry of the DUT (including the cables
connected to the DUT) by at least 0.1 m. The size should be at least 1.6 m ×
0.8 m. The height of the HCP above the GRP shall be between 0.7 m and 1.0
m. The GRP should have at least the dimensions of the HCP.
6.5 Insulation block
Insulation blocks, if used, shall be constructed of clean non-hygroscopic
material (e.g. polyethylene). The relative permittivity should range between 1
and 5. The blocks shall be (50 ± 5) mm in thickness and extend beyond the test
set-up by at least 20 mm on all sides.
6.6 Insulation support
Insulation support, if used, shall be constructed of clean non-hygroscopic
material (e.g. polyethylene) with a relative permittivity between 1 and 5. The
support shall be between 2 mm and 3 mm in thickness and project beyond the
test set-up by at least 20 mm on all sides. Care shall be taken that support
prevents dielectric breakdown up to 25 kV of discharge voltage.
7 Discharge modes
7.1 General
During the test, discharges can be applied by two discharge modes: contact
and air. See Annex D for guidance on air versus contact discharge modes.
7.2 Contact discharge
In contact discharge mode, before applying the discharge, the tip of the ESD
generator’s discharge electrode is brought in contact with the DUT.
7.3 Air discharge
In air discharge mode, the discharge electrode is charged to the test voltage
and then brought with the demanded speed of approach to the DUT, applying
the discharge through an arc that happens when the tip approaches close
enough to the DUT to break down the dielectric material between the tip and
test point.
The speed of approach of the discharge electrode is a critical factor in the rise
time and amplitude of the injected current during an air discharge. The speed
of approach should be between 0.1 m/s and 0.5 m/s. In practice the ESD
generator should approach the DUT as quickly as possible until the discharge
occurs or the discharge tip touches the discharge point without causing damage
to the DUT or generator.
8 Component test method (DUT powered-up)
8.1 General
These tests consist of direct and indirect types of application of discharges to
the DUT, as follows:
- direct type discharges (contact or air discharge mode) are applied directly
to the DUT or to the remote parts that are accessible, e.g. switches and
buttons;
- indirect type discharges (contact discharge mode) simulate discharges that
occur to other conductive objects in the vicinity of the DUT and are applied
through an intervening metal, such as an HCP.
Note: An optional test set-up and procedure using direct discharge test method are
described in Annex E.
The ESD generator shall be configured with the 330 pF or 150 pF capacitor,
depending on the DUT location in the vehicle, and the 330 Ω resistor. If the DUT
location is not specified, the 330 pF capacitor shall be used.
Conductive surfaces shall be tested using contact mode discharges. For
contact discharge, use the contact discharge tip (see Figure 1). Air discharge
may also be applied to conductive surfaces, if required in the test plan. Non-
conductive surfaces shall be tested using air mode discharges. For air
discharge, use the air discharge tip (see Figure 2).
Before applying any discharges to the DUT, according to Annex A, it shall
periodically verify the ESD generator.
8.2 Test plan
Prior to performing the test, generate a test plan, including the following:
- the detailed test set-up;
- test points;
- mode of operation of DUT;
- any special instructions and changes from the standard test.
8.3 Test procedure for direct discharges
8.3.1 General
Discharges shall be applied to all specified test points with the equipment
operating in normal modes. Product response may be affected by the polarity
of the discharge. Both polarities of discharge shall be used.
8.3.2 Test set-up
Place the DUT on the HCP (see Figure 5). If the DUT is, when installed, directly
connected to the body, during the test, it shall be placed directly on the HCP. If
it is not connected to the body during installation, during the test, an insulation
support shall be placed between the DUT and the HCP.
For testing, the DUT shall be connected to all peripheral units necessary for
functional testing. The line lengths used should be between 1.50 m and 2.50 m.
If vehicle intent peripheral units are not available for testing, substitute
peripheral units and test discharge points shall be addressed in the test plan.
All components on the test table shall be a minimum distance of 0.2 m from
each other. The lines shall be laid in such a way that they run parallel to the
HCP edges and they shall be a distance of 0.1 m away from the HCP edges.
The lines should be bundled and shall be secured on an insulating block. The
wiring type is defined by the actual vehicle. The supply battery shall be on the
test table, with the negative terminal of the battery directly connected to the
HCP. The explosion hazard of the battery shall be taken into account and
appropriate protective measures taken.
For direct discharge, the discharge return cable of the ESD generator shall be
connected to the HCP. The discharge return cable of the generator shall be kept
at least 0.2 m away from the DUT and all cables connected to the DUT (to
reduce coupling from this cable which might affect the test results). The ESD
test bench (test surface) shall be a minimum of 0.1 m from other conductive
structures, such as the surfaces of a shielded room.
Figure 5 -- Test set-up for direct discharge
8.3.3 Electrode connections for direct discharge method
8.3.3.1 Contact discharge
Before contact discharges, the tip of the discharge electrode of ESD generator
shall touch the DUT.
Where painted surfaces cover a conducting substrate, if the coating is not
declared to be an insulating coating by the equipment manufacturer, then the
pointed tip of the generator penetrates the coating so as to make contact with
the conducting substrate.
8.3.3.2 Air discharge
In the case of air discharges, the tip of the discharge electrode shall be brought
sufficiently close to the DUT as quickly as possible.
Note: When the case is a non-conductive surface, or the coating is declared to be an
insulating coating for the conductive surfaces, then the surface is tested as an
insulating surface using the air discharge mode.
8.3.4 Orientation of ESD generator
For direct discharge, the ESD generator’s discharge tip is held perpendicular to
the surface of the DUT when possible; if not possible, an angle of at least 45°
to the surface of the DUT is preferred.
8.3.5 Number of discharges and time between ESD events
At least 3 discharges shall be applied to all direct discharge test points for each
specified test voltage and polarity (see Annex C). The time interval between
successive single discharges shall be as long as necessary, not less than 1 s,
in order to ensure that the charges are removed before new discharge. The
methods for removing the charges described below can be applied.
- Charge build-up of the DUT can be eliminated by briefly connecting a
bleeder wire with resistance (≥ 1 MΩ) in the following sequence: (1)
between the discharge location and ground, and (2) between the ground
point of the DUT and ground. If there is evidence that the tandem
connection of 1 MΩ wire does not have any impact on the test result, it can
remain connected to the DUT.
- If the time interval is lengthened between two successive discharges, the
build-up charge vanishes due to the natural charge decay.
- Air-ionizers may be used to speed up the “natural” discharging process of
the DUT. The ionizer shall be turned off when applying an air discharge test.
8.3.6 Test voltage
The test voltages shall be increased, using at least two values, up to the
maximum test level.
Note: Some products have the tendency to exhibit susceptibility responses when exposed
to specific test voltages, but not necessarily at other test voltage levels.
8.4 Test procedure for indirect discharges
8.4.1 General
Discharges to objects placed or installed near the DUT are simulated by
applying contact discharges of the ESD generator to a horizontal coupling plane
(HCP). Contact discharges shall be applied to the HCP at points on each side
of the DUT. The ESD pulse should be applied to the edges of the HCP. The
DUT shall be positioned on the HCP such that its closest surface is 0.1 m from
the edge of the HCP receiving the discharge. The DUT may need to be
repositioned during the test, when applying ESD to the edge of the HCP, in
order to maintain this 0.1 m spacing between the DUT edge and the edge of
the HCP.
8.4.2 Test set-up
Place the DUT on the HCP (see Figure 6). If the DUT is, when installed, directly
connected to the body, during the test, it shall be placed directly on the HCP. If
it is not connected to the body during installation, during the test, an insulation
support shall be placed between the DUT and the HCP.
For testing, the DUT shall be connected to all peripheral units necessary for
functional testing. The line lengths used should be between 1.50 m and 2.50 m.
If vehicle intent peripheral units are not available for testing, substitute
peripheral units and test discharge points shall be addressed in the test plan.
All components on the test table shall be a minimum distance of 0.2 m from
each other. The lines shall be laid in such a way that they run parallel to the
HCP edges and the plane and they shall be a distance of 0.1 m away from the
HCP edges. The lines should be bundled and shall be secured on an insulating
block. The wiring type is defined by the actual vehicle. The supply battery shall
be on the test table, with the negative terminal of the battery directly connected
to the HCP. The explosion hazard of the battery shall be taken into account and
appropriate protective measures taken.
For indirect discharge, the discharge return cable of the ESD generator may be
connected to the HCP or to the GRP (as defined in the test plan). The discharge
return cable of the generator shall be kept at least 0.2 m away from the DUT
and all cables connected to the DUT (to reduce coupling from this cable which
might affect the test results). The ESD test bench (test surface) shall be a
minimum of 0.1 m from other conductive structures, such as the surfaces of a
shielded room.
Figure 6 -- Test set-up for indirect discharge
8.4.3 Number of discharges and time between ESD events
50 discharges shall be applied to all indirect discharge test points for each
specified test voltage and polarity (see Annex C). For discharges to the HCP,
the time intervals between successive single discharges shall be longer than
50 ms.
8.4.4 Orientation of ESD generator
For discharges to HCP, the discharge tip is in the same plane as the HCP while
making contact with the edge of the plane. No discharge is made to the flat
surface of the HCP.
8.4.5 Test voltage
It shall be in accordance with 8.3.6.
9 Component test method (DUT unpowered)
9.1 General
The test shall subject the DUT to simulated direct discharges from humans
during the assembly process or in the service case.
Before applying any discharges to the DUT, according to Annex A, it shall
periodically verify the ESD generator. The ESD generator shall be configured
with the 150 pF capacitor and the resistor value specified in the test plan.
9.2 Test plan
Prior to performing the test, generate a test plan, including the following:
- the detailed test set-up;
- test points;
- mode of operation of DUT;
- any special instructions from the standard test.
9.3 Test procedure
9.3.1 General
The test shall be performed by contact discharge on all pins and contacts,
and/or air discharge mode on all surfaces and points that can be touched during
the assembly process or in the service case.
Apply the ESD at (as a minimum) each connector pin (including recessed
connector pin of DUT), case, button, switch, display, case screw and case
opening that is accessible during handling. To access recessed connector pins,
an insulated solid wire with a cross-section between 0.5 mm2 and 2 mm2 and a
maximum length of 25 mm shall be used.
Discharge on pins of a connector with closely-spaced pins may be difficult. In
this case, it is possible to use insulated solid wire with a cross-section between
0.5 mm2 and 2 mm2, and a maximum length of 25 mm to access.
Direct discharges shall be applied to all specified test points in the test plan.
Product response may be affected by the polarity of the discharge. Both
polarities of discharge shall be used.
9.3.2 Test set-up
The ESD test set-up is shown in Figure 7. The safety ground connection (item
7 in Figure 6) may include 2 × 470 kΩ resistors. The DUT shall be tested without
periphery, as delivered by the supplier.
If required in the test plan, a static dissipative mat shall be used between DUT
and HCP. The size of the mat shall be greater than the horizontal projection size
of DUT. The surface resistivity of this material shall be between 107 Ω per
square and 109 Ω per square.
For direct discharge, the discharge return cable of the ESD generator shall be
connected to......
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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