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Interpretation of Chery Automobile Electronic Parts EMC Standard -Q/SQR.04.748-2008
Release time:
2022-12-13 00:00
Source:
Abstract
The test methods, evaluation indexes and evaluation requirements of test results of electromagnetic compatibility of automobile electronic components stipulated in Q/SQR.04.748-2008 are introduced.
Key words
Electromagnetic compatibility; Automobile electronic parts; Conduction emission; Transient emission; Radiation emission; High current injection anti-interference; Radiation anti-jamming; Portable transmitter anti-jamming; Magnetic field anti-interference; Electrostatic discharge;
1 Introduction
Q/SQR.04.748-2008 Released on 2008-09-01, it stipulates the EMC requirements of electric and electronic components of 12V system for automotive products of Chery Company.
Note: Powertrain part is not included.
2 General Requirements
Disturbance resistance test requirements/levels are classified according to the importance level of electrical functions, III is the highest importance, and different levels have different anti-interference requirements.
Class I: convenience function;
Class II: Important function, but not necessary;
Category III: Mandatory regulations and functions related to personal safety and their very important functions. Examples of functional importance hierarchy (reference).
| Function |
I |
II |
III |
| Seat operation | Seat adjustment, position memory and seat heating |
/ |
/ |
| External light operation | Headlight adaptive adjustment | License plate light and daytime running light operation | Reverse lights operate brake lights and high brake lights |
| Internal light operation | Internal light operation |
/ |
|
| Turn signal operation |
/ |
/ |
Turn signal operation |
| Engine operation |
/ |
/ |
Engine operation |
| Electric glass |
/ |
/ |
Electric glass |
| Central control |
/ |
Central control |
/ |
| Remote control |
/ |
Remote control |
/ |
| Body anti-theft |
/ |
/ |
Body anti-theft |
| Engine anti-theft |
/ |
/ |
Engine anti-theft |
| Trunk open |
/ |
Trunk open |
/ |
| Front hatch open |
/ |
Front hatch open |
/ |
| Fuel tank cap open | Fuel tank cap open |
/ |
/ |
| Automatic climate |
/ |
/ |
/ |
| Defrosting | Defrosting of rear windlass |
/ |
Defrost front windlass |
| Instrument indication | Instrument convenience indication |
|
Meter fault information indicates odometer and speedometer |
| Low brake oil pressure alarm |
/ |
/ |
/ |
| Heating nozzle | Heating nozzle |
/ |
/ |
| Directional Angle sensor |
/ |
/ |
Directional Angle sensor |
| Cruise control |
/ |
/ |
Cruise control |
| Rainfall sensor operation | Rainfall sensor operation |
/ |
/ |
| Ceiling operation | Ceiling operation |
/ |
/ |
| Data bus system |
/ |
/ |
Data bus system |
| Horn operation |
/ |
/ |
Horn operation |
| Rearview mirror operation |
/ |
/ |
Rearview mirror operation |
| Seat belt operation |
/ |
/ |
Seat belt operation |
3. Detailed requirements for test items
The EMC test items for components and their systems depend on the type of electronic and electrical components they contain. Different components have different EMC test project requirements.
Electrical and electronic parts that work all the time in the process of driving are of continuous type.
Electrical and electronic parts that are opened according to the user's needs and have a long working time, generally more than 1min, belong to the long-term type.
Electrical and electronic parts opened according to the needs of users, the single working time is short, generally within 1min, belonging to the short-time type.
3.1 Power line RF conduction emission - voltage method
Category of applicable electronic and electrical components:
1) Class A - Electronic modules and components (with processor), such as: BCM, instrument, fan controller, host, air conditioning panel, etc.
2)BM type -- brush commutator motors, such as door and window motors, wiper motors, warm air motors, rearview mirror regulating motors, washing motors, electric skylights, etc.;
3)HF -- inductive components with operating frequency greater than 100Hz, such as: tweeter, woofer, loudspeaker, common anti-theft horn, etc.
Only EUT power cables are measured. The test method and test equipment refer to CISP 25 standard.
Test frequency range: 150kHz~108MHz
The narrowband limit requirements are shown in the table below, between CISPR 25 levels 3 and 4:
| Test frequency class | Frequency range |
Narrow band limit(dBμV) |
| Peak value | ||
|
1 |
0.15MHz～0.3MHz |
77 |
|
2 |
0.53MHz-2.0MHz |
55 |
|
3 |
5.9MHz～6.2MHz |
48 |
|
4 |
30MHz～54MHz |
43 |
|
5 |
68MHz～87MHz |
33 |
|
6 |
87MHz～108MHz |
39 |
Broadband limit requirements, between CISPR 25 Levels 2 and 3:
| Test frequency class | Frequency range |
Broadband limit(dBμV) |
|
| Peak value | Quasi-peak | ||
|
1 |
0.15MHz～0.3MHz |
100 |
87 |
|
2 |
0.53MHz～2.0MHz |
84 |
71 |
|
3 |
5.9MHz～6.2MHz |
68 |
55 |
|
4 |
30MHz～54MHz |
68 |
55 |
|
5 |
68MHz～108MHz |
52 |
39 |
The test layout diagram is identical to CSIPR 25:
Figure 1 Grounding the remote end of the EUT power return cable
Figure 2 Grounding the near end of the EUT power return wire
FIG. 3 Alternator and generator test layout
3.2 Radiation emission - antenna measurement method
Category of applicable electronic and electrical components:
1) Class A - Electronic modules and components (with processor), such as: BCM, instrument, fan controller, host, air conditioning panel, etc.
2)BM type -- brush commutator motors, such as door and window motors, wiper motors, warm air motors, rearview mirror regulating motors, washing motors, electric skylights, etc.;
The frequency range of radiation emission measurement is 150kHz ~ 1GHz. Refer to CISPR 25 for test methods.
Test frequency band and test antenna requirements:
1) Unipolar vertical antenna is used for measurement in the frequency range of 150kHz ~ 30MHz;
2) The frequency range of 30MHz ~ 200MHz is measured by using a double-cone antenna, including vertical polarization and horizontal polarization directions;
3) log-periodic antennas are used for measurement in the frequency range of 200MHz ~ 1000MHz, including vertical and horizontal polarization directions.
The narrow-band limit requirements are shown in the following table:
| Test frequency class | Frequency range |
Narrow band limit(dBμV/m) |
|
| Peak value | Average value | ||
|
1 |
0.15MHz～0.3MHz |
48 |
/ |
|
2 |
0.53MHz～2.0MHz |
39 |
/ |
|
3 |
5.9MHz～6.2MHz |
37 |
/ |
|
4 |
30MHz～54MHz |
37 |
/ |
|
5 |
68MHz～87MHz |
27 |
/ |
|
6 |
87MHz～108MHz |
30 |
/ |
|
7 |
142MHz～175MHz |
27 |
/ |
|
8 |
380MHz～512MHz |
34 |
/ |
|
9 |
820MHz～960MHz |
40 |
/ |
|
10 |
Other bands between 30MHz and 1000MHz (Note: EU requirements) |
/ |
40 |
Broadband limit requirements are shown in the table below:
| Test frequency class | Frequency range (Hz) |
Broadband limit(dBμV/m) |
|
| Peak value | Quasi-peak | ||
|
1 |
0.15MHz～0.3MHz |
83 |
70 |
|
2 |
0.53MHz～2.0MHz |
72 |
59 |
|
3 |
5.9MHz～6.2MHz |
51 |
38 |
|
4 |
30MHz～54MHz |
51 |
38 |
|
5 |
68MHz～108MHz |
40 |
27 |
|
6 |
142MHz～175MHz |
40 |
27 |
|
7 |
380MHz～512MHz |
47 |
34 |
|
8 |
820MHz～960MHz |
53 |
40 |
|
9 |
Other bands between 30MHz and 1000MHz (Note: EU requirements) |
70 |
50 |
The test layout requirements are the same as CISPR25:
Figure 4. Measurement of radiating antenna
3.3 Transient voltage emission
Category of applicable electronic and electrical components:
1)BM Class -- brush commutator motors, such as door and window motors, wiper motors, warm air motors, rearview mirror regulating motors, washing motors, electric skylights, etc.
2) Class I -- inductive components such as relay coil and solenoid, with power greater than 10W
3)HF -- inductive components with operating frequency greater than 100Hz, such as: tweeter, woofer, loudspeaker, common anti-theft horn, etc.
To test the transient voltage emission of the working power lines of components, refer to ISO 7637-2 for test methods and test equipment.
When the pulse width is less than 100μs(starting and ending at 10% of the pulse amplitude), the voltage emission limit is +100V/-150V. When the pulse width is greater than 100μs, the voltage emission limit is +50V/-100V;
FIG. 5 Transient voltage conduction emission test layout
3.4 High current injection anti-interference
Category of applicable electronic and electrical components:
1) Class A - Electronic modules and components (with processor), such as: BCM, instrument, fan controller, host, air conditioning panel, etc.
To examine the resistance of parts to narrow-band electromagnetic energy radiation, test methods and test equipment refer to ISO 11452-4.
The test frequency range was 1MHz ~ 400MHz, and the injection intensity was 66mA.
Function Class I Function failure status Level C; Function Class II and III Function failure status Level A.
The test layout is as follows:
FIG. 6 Layout of high current injection test
3.5 Radio frequency Anti-jamming - antenna injection method
Category of applicable electronic and electrical components:
1) Class B -- Control modules that are not connected with the vehicle harness, such as tire pressure sensors;
2) Category A - Electronic modules and components (with processor), such as BCM, instrument, fan controller, host, air conditioning panel, etc.
To examine the resistance of parts to narrow-band electromagnetic energy radiation, test methods and test equipment refer to ISO 11452-2.
The test frequency range was 200MHz ~ 2000MHz, and the injection intensity was 33V/m.
Function Class I Function failure status Level C; Function Class II and III Function failure status Level A.
The test layout is as follows:
FIG. 7 Test layout of anechoic chamber with ground plane (log-periodic antenna 200MHz ~ 1000MHz)
FIG. 8 Test layout of anechoic chamber with ground plane (horn antenna 1000MHz ~ 2000MHz)
3.6 Magnetic Field Anti-interference
Category of applicable electronic and electrical components:
1) Class M - magnetic components, such as: mileage sensor, etc.;
The ability of parts to resist magnetic field and interference is examined. The test method and test equipment refer to ISO 11452-8.
The test frequency ranges from 15Hz to 150kHz. The test grades and criteria are as follows.
|
Frequency range(Hz) |
Test strength (internal field strength A/m) | Function class I | Function Class II and III |
|
15－1000 |
30 |
C |
A |
|
1000－10000 |
30(f/1000)2 |
C |
A |
|
10000－150000 |
0.3 |
C |
A |
FIG. 9 Magnetic field anti-interference test layout
3.7 Power Cable Transient Anti-interference
Category of applicable electronic and electrical components:
1) Class P -- passive electrical components and modules, such as resistors, capacitors, limiting diodes and other components;
2) Category A - Electronic modules and components (with processor), such as BCM, instrument, fan controller, host, air conditioning panel, etc.
To examine the resistance of components to transient voltage pulses of power lines, test methods and test equipment refer to ISO 7637-2, common impulse tests 1, 2a, 2b, 3a, 3b, 4 and 5b.
The test object of transient conduction anti-interference is the power line. Test methods: Pulse pulse 1, 2a, 2b, 3a, 3b, 4 and 5b were tested according to ISO 7637.2 standard. The test grades were the highest in the reference standards.
Transient conduction immunity requirement
| Pulse type | Voltage Us | Test time | Functional status requirements of parts | ||
| Class I function | Class II function | Class III function | |||
|
1 |
-100V |
5000 pulses |
C |
C |
C |
|
2a |
50V |
5000 pulses |
C |
A |
A |
|
2b |
10V |
10 pulses |
C |
C |
C |
|
3a |
-150V |
1 hour |
C |
A |
A |
|
3b |
100V |
1 hour |
C |
A |
A |
|
5b |
87V |
1 pulse |
C |
A |
A |
|
Note: 5b pulse, for a vehicle with a voltage suppressor generator, Us is its voltage suppressor value. |
|||||
3.8 I/O line transient conduction Anti-interference
Category of applicable electronic and electrical components:
1) Category A - Electronic modules and components (with processors), such as BCM, instrument, fan controller, host, air conditioner panel, etc.
The test object of transient coupling anti-jamming is signal/control line, and the test method is based on ISO 7637.3 standard. CCC method is adopted, and test grades and criteria are as follows.
| Test pulse | Test Class III | Minimum pulse number or test time | Function class I |
Function II. Class III |
| Pulse a |
－40V |
10min |
C |
A |
| Pulse b |
30V |
10min |
C |
A |
The test layout is as follows:
FIG. 10 Capacitive coupled forceps (CCC) test layout
3.9 Anti-interference of electrostatic discharge
Category of applicable electronic and electrical components:
1) Class P -- passive electrical components and modules, such as resistors, capacitors, limiting diodes and other components;
2) Class B -- control modules that are not connected with the vehicle harness, such as tire pressure sensors;
3) Category A - Electronic modules and components (with processor), such as BCM, instrument, fan controller, host, air conditioning panel, etc.
Test the antistatic discharge ability of the parts, test methods and test equipment meet the requirements of ISO 10605.
The test is divided into passive mode discharge test and EUT operating mode direct coupling test.
Passive mode discharge test
-- During the test, the device under test is not connected to power supply and load;
Test point: all possible surfaces and points that people may contact in the process of assembly and disassembly;
- After the test, carry out functional test.
- The test grade is as follows:
| Discharge type | Severity rating | Discharge frequency |
Functional failure pattern State level requirement |
| Direct contact discharge |
±6kV |
3 |
C |
| Air discharge |
±15kV |
3 |
C |
FIG. 11 Discharge test layout in passive mode
Direct coupling in active mode
- If the EUT is in active mode, the input and output must be connected.
- The test grade is as follows:
| Discharge type | Severity rating | Discharge frequency |
Function failure state, etc Grade requirement |
| Direct contact discharge |
±6kV |
3 |
C |
| Air discharge |
±8kV |
3 |
C |
FIG. 12 Layout of EUT test bed in active mode
4 Conclusion
Chery automotive electronic components EMC technical requirements, including equipment requirements, test methods, etc., relative to CISPR 25, completely equivalent to this standard, no special requirements, only slightly adjusted/changed in the immunity test grade.