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Interpretation of Nissan Automotive Electronics EMC Standards—Comparison of Transient Conduction Immunity and Electrical Performance Tests with ISO International Standards
Release time:
2022-07-02 00:00
Source:
Nissan's automotive electronics EMC test standard is currently in accordance with 28401NDS02 [5], and the latest revision is 2006.3.29.
Among them, items related to transient conduction immunity and electrical performance testing are compared with the corresponding international standards ISO7637 and ISO16750-2. Some of them are still in use; some of them are only borrowed by Nissan and differentiated in terms of requirements; some are completely Nissan. Unique, no international standard to rely on.
First, let's look at the test items that basically follow the ISO international standard.
1. Among them, the electrical performance test items are as follows:
6.1. RESISTANCE TO ELECTRICAL DISTURBANCES TESTS
6.1.1. EQ/TE 01 : Resistance to power supply voltages
6.1.2. EQ/TE 02 : Resistance to slow decrease and increase power of supply voltages
6.1.3. EQ/TE 03 : Re-initialization test
6.1.4. EQ/TE 04: Resistance to non-usual power supply voltages
6.1.5. EQ/TE 05: Resistance to ground and positive supply voltages short circuit
On this basis, the Nissan standard puts forward some more thoughtful and detailed requirements on some test details, which involve the following:
1. In terms of test layout,
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
2. In terms of test procedures, the running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse injection) is clearly stipulated. - (needs to run for at least 10 minutes)
3. Make clear requirements on the waveform calibration parameters before the test.
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
2. Among them, the test items involving transient conduction immunity are as follows:
6.2.1. EQ/IC 07: Immunity to signal line transients
On this basis, the Nissan standard puts forward some more thoughtful and detailed requirements on some test details, which involve the following:
1. In terms of test layout,
a) It clearly stipulates the selection of CCC method (capacitive coupling clamp method)
b) The height of the insulating pad of the EUT and the wiring harness is clearly specified. -(50mm)
c) The length of the EUT power cord is clearly specified. -(0.2m)
d) The surrounding facilities of the EUT test: the placement of sensors, start-up excitation devices and the length of the wiring harness are clearly specified (as shown in the figure below).
e) The length of the EUT signal line is clearly specified. -(1m)
f) It clearly stipulates that a 50-ohm load needs to be loaded on the side of the capacitive coupling clamp close to the load in the test. (As shown below)
2. In terms of test procedures, the running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse injection) is clearly stipulated. - (needs to run for at least 10 minutes)
3. Make clear requirements on the waveform calibration parameters before the test.
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
Secondly, let's look at the test items that only borrow from the ISO international standard and have obvious differences in requirements.
1. Among them, the electrical performance test items are as follows:
6.1.10. EQ/IC 04: Resistance to power supply micro-interruptions
6.1.11. EQ/IC 05: Resistance to starting profile
6.1.12. EQ/IC 06: Resistance to on-board power system voltage ripples
Next, we expand the narrative one by one:
6.1.10. EQ/IC 04: Resistance to power supply micro-interruptions
1. The test requirements are based on 4.6.1 Momentary drop in supply voltage of ISO16750-2. The difference is that the ISO standard has relatively simple requirements for waveforms. Only one waveform needs to be measured, and the rising edge/falling edge does not exceed 10ms, see the figure below for details:
12V system
24V system
The Nissan standard needs to measure a lot of waveforms, which can be summarized as follows:
Ø 10 µs micro interrupt
Ø 100 µs micro interrupt
Ø 5 ms micro interrupt
Ø 50 ms micro-interrupt EUT in engine start state
Ø 50 ms micro interrupt EUT is not in the engine start state
Ø 300 ms micro interrupt
2. In terms of test layout and test configuration, Nissan standard is more complicated than ISO16750, and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) It is clearly stipulated that the EUT needs to be connected in parallel with an external 2-ohm load.
e) The test configuration clearly stipulates that an oscilloscope, electronic switch, power supply, and battery are required. The layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires layout according to the above figure, and a 1k ohm load is replaced at the EUT position, and the test waveform meeting the requirements is achieved after debugging at the oscilloscope end. Then proceed to the EUT test. The detailed waveform parameters are shown in the figure below:
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
6.1.11. EQ/IC 05: Resistance to starting profile
1. The test requirements refer to the test waveform of 4.6.3 Starting profile (starting voltage) of ISO16750-2, as shown in the figure below:
The difference is that the waveform level of the ISO16750-2 standard is shown in the figure below:
12V system
The Nissan standard waveform, as shown in the table below, is compared with ISO16750, and the following conclusions can be drawn:
Ø Level I(*) of Nissan standard basically corresponds to I of ISO standard
Ø The level II of the Nissan standard basically corresponds to the II of the ISO standard
Ø Levels I and III of the Nissan standard are relatively unique, and there is no corresponding ISO waveform level.
|
No |
I Start-stop system |
I（*） |
II |
III |
|
parameter |
|
|
|
|
2. In terms of test layout and test configuration, Nissan standard is more complicated than ISO16750, and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) The test configuration clearly stipulates that an oscilloscope, generator, power supply, and battery are required, and the layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires layout according to the above figure, waveform calibration is performed under the EUT open circuit state (disconnected), and the test waveform meeting the requirements is achieved after debugging at the oscilloscope end. Then proceed to the EUT test.
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
6.1.12. EQ/IC 06: Resistance to on-board power system voltage ripples
1. The test requirements refer to the test waveform of 4.4 Superimposed alternating voltage (superimposed AC voltage) of ISO16750-2, as shown in the figure below:
The difference is that the waveform level and sweep parameters of the ISO16750-2 standard are detailed in the following four items and waveforms:
Ø 等级1: peak to peak voltage, U PP , of 1 V, for U N = 12 V and U N = 24 V;
Ø 等级2: peak to peak voltage, U PP , of 4 V, for U N = 12 V and U N = 24 V;
Ø 等级3: peak to peak voltage, U PP , of 10 V, for U N = 24 V only;
Ø 等级4: peak to peak voltage, U PP , of 2 V, for U N = 12 V
Unit: f(Hz), t(second)
For the waveform level and frequency sweep parameters of the Nissan standard, see the following two and the waveform for details.
Ø 2 V (peak-to-peak) between 50 Hz and 50 kHz (corresponding to the sweep spectrum in the left figure below)
Ø 4 V (peak-to-peak) between 50 Hz and 20 kHz (corresponding to the sweep spectrum in the right figure below)
Compared with ISO16750, the following conclusions can be drawn:
Ø There are only 2 grades in the Nissan standard, while there are 4 grades in the ISO standard, and there is no one-to-one correspondence between the two.
Ø The Nissan standard has 2 sweep spectrum diagrams, which are different from the ISO standard sweep spectrum diagrams.
2. In terms of test layout and test configuration, Nissan standard is more complicated than ISO16750, and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) The test configuration clearly stipulates that an oscilloscope, generator, power supply, and battery are required, and the layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires the layout as shown in the figure above, the oscilloscope selects the high-impedance input mode, replaces it with a 500 milliohm load at the EUT position, and achieves the required test waveform after debugging at the oscilloscope end. Then proceed to the EUT test.
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
2. Among them, the test items involving transient conduction immunity are as follows:
6.1.6. EQ/IC 01: Resistance to pulses 1 and 1 bis and 2a
6.1.7. EQ/IC 02: Resistance to pulses 3a and 3b
6.1.9. EQ/IC 03: Resistance to pulse 5b
Next, we expand the narrative one by one:
6.1.6. EQ/IC 01: Resistance to pulses 1 and 1 bis and 2a
1. The test requirements refer to the test waveforms of Test pulse 1 and Test pulses 2a of ISO7637-2, as shown in the figure below:
Test pulse 1
Test pulse 2a
For the Nissan standard waveform, see the figure below:
Comparing the waveform of the Nissan standard with the ISO7637-2 waveform, the following conclusions can be drawn:
Ø Added Pulse 1 bis to Nissan standard
Ø The Nissan standard specifies the test pulse voltage value in the waveform parameters (Ua in Nissan is equal to Us in ISO)
Ø The t value in Nissan's standard waveform parameters is exactly the same as that of ISO.
Then compare the pulse implementation times/times in the Nissan standard and the ISO7637-2 standard (as shown in the table below), and the following conclusions can be drawn:
Ø The Nissan standard specifies the number of pulses as 5000, which is much more than the 500 required by ISO.
Ø The Nissan standard specifies the test pulse voltage level value in the waveform parameters, which has no corresponding relationship with the three level values of ISO7637-2.
|
standard |
describe |
|
Nissan |
Pulse 1 and 1 bis: 5000 pulses of - 100 V |
|
Pulse 2a: 5000 pulses of + 100 V |
|
|
ISO7637-2 |
12V system |
2. Compared with ISO7637-2 in terms of test layout and test configuration, the Nissan standard is more complicated and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) It is clearly stipulated that the EUT needs to be connected in parallel with an external 2-ohm load ((as shown in the figure below)).
e) The test configuration clearly stipulates that an oscilloscope, generator, power supply, and battery are required, and the layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires layout according to the above figure, waveform calibration is performed in the EUT open circuit state (disconnected), the oscilloscope selects the high-impedance input mode, and the test meets the requirements after debugging at the oscilloscope end waveform. Then proceed to the EUT test.
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
6.1.7. EQ/IC 02: Resistance to pulses 3a and 3b
1. The test requirements refer to the test waveforms of Test pulse 3a and Test pulses 3b of ISO7637-2, as shown in the figure below:
Test pulse 3a
Test pulse 3b
Test pulse 3a/3b 12V system test level and pulse quantity
For the Nissan standard waveform, see the figure below:
Pulse 3a
Pulse 3b
Comparing the waveform of the Nissan standard with the ISO7637-2 waveform, the following conclusions can be drawn:
Ø The f frequency in the Nissan standard is a changing value (increase from 1 kHz to 100 kHz in the first 30 minutes, drop from 100 kHz to 1 kHz in the next 30 minutes, and the maximum frequency step is 1 kHz), and the synchronous t1 value is 10us-1ms changes within this range. And f in ISO7637-2 is a fixed value (that is, the reciprocal of t1=100us, that is, 10kHz)
Ø The t value (except t1) in the Nissan standard waveform parameters is exactly the same as that of ISO7637-2.
Ø The Nissan standard test pulse period is 60 minutes, which is equivalent to the ISO required test period of 1 hour.
Ø The Nissan standard specifies the test pulse voltage level value in the waveform parameters, which has no corresponding relationship with the three level values of ISO.
2. Compared with ISO7637-2 in terms of test layout and test configuration, the Nissan standard is more complicated and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) The test configuration clearly stipulates that an oscilloscope, generator, power supply, and battery are required, and the layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires layout according to the above figure, waveform calibration is performed in the EUT open circuit state (disconnected), the oscilloscope selects the high-impedance input mode, and the test meets the requirements after debugging at the oscilloscope end waveform. Then proceed to the EUT test.
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
6.1.9. EQ/IC 03: Resistance to pulse 5b
1. The test requirements refer to the old version of ISO7637-2 (version 04) test pulse 5b, which is the test waveform of Test B in 4.6.4 Load dump in ISO16750-2, as shown in the figure below:
Test B
For the Nissan standard waveform, see the figure below:
Pulse 5a (Refer to this figure for the calibration setting Vs value)
Pulse 5b (Nissan standard requires test pulse number: 5 times)
Comparing the waveform of the Nissan standard with the ISO7637-2 waveform, the following conclusions can be drawn:
Ø Nissan standard only needs to test Pulse 5b, while ISO16750-2 also needs to test Test A (ie Pulse 5a)
Ø The t value in Nissan standard waveform parameters is basically consistent with ISO16750-2.
Ø Nissan standard test pulse number is 5 times, which is consistent with the test number required by ISO.
Ø The test pulse clamping voltage level value in the Nissan standard waveform parameters is 21.5V, which is lower than the ISO level value of 35V (12V system).
2. In terms of test layout and test configuration, the Nissan standard is more complicated than ISO16750-2, and has many more requirements, as follows:
a) The height of the insulation mat of the EUT and the wiring harness is clearly specified. -(50mm)
b) The length of the EUT power cord is clearly specified. -(0.2m)
c) The surrounding facilities of the EUT test: the placement of sensors and start-up excitation devices are clearly stipulated (as shown in the figure below).
d) The test configuration clearly stipulates that an oscilloscope, generator, power supply, and battery are required, and the layout is as follows:
3. In the test procedure,
a) The calibration scheme before the test is proposed, which requires waveform calibration under no-load condition according to the requirements in the table below. The terminal is debugged to meet the requirements of the test waveform. Then proceed to the EUT test.
b) The running time (also known as warm-up time) of the EUT before the test (that is, before the test pulse is injected) is clearly stipulated. - (needs to run for at least 10 minutes)
4. For the writing of the test report, there are clear requirements on what information needs to be reflected.
5. There are clear requirements for the test judgment level.
Finally, let's look at the test items that are completely unique to Nissan and have no international standards to rely on.
The relevant test items are as follows:
6.2.3. EQ/IC 09: Immunity to ignition high voltage
6.1.8. EQ/IC 10: Resistance of inductive load connected circuits
6.2.4. EQ/IC 11: Resistance to impulsive transient
Next, we expand the narrative one by one:
6.2.3. EQ/IC 09: Immunity to ignition high voltage
1. The test waveform and test layout are shown in the figure below, and the test points are as follows:
Ø Apply high voltage pulses - 10 kV and + 10 kV to a terminal load of 15 kΩ ("Resistive load" in EQ/IC 09 test layout diagram) for 10 minutes each.
Ø The length of the coupled part of the EUT harness is at least 1 m, and the coupling distance is 100 mm. (the distance between the parallel EUT harness and the high-voltage line)
Ø LISN needs to comply with CISPR 25, connected to 50 Ω load.
EQ/IC 09 test waveform
EQ/IC 09 Test Layout
2. The precautions for the test implementation steps are as follows:
Ø The maximum length of the EUT harness shall not exceed 2m.
Ø The EUT and wiring harness must be placed on an insulating pad with a height of 50mm.
Ø The EUT needs at least 10 minutes of continuous running time before the test (that is, before the test pulse injection) (also can be understood as the warm-up time)
Ø The writing of the test report needs to reflect the following information: test layout, abnormal phenomenon data in the test, test generator characteristics and waveform diagram.
6.1.8. EQ/IC 10: Resistance of inductive load connected circuits
1. This test consists of two tests, (1) actual inductive load method and (2) simulated (standby) load method. The test waveform and test layout are shown in the figure below, and the main points of the test are as follows:
|
test mode |
Test parameters/levels |
|
|
Mode 1: Adequate rated current; and operation under rated mechanical load conditions |
1000 switching operations |
|
|
Mode 2: Operates with actual inductive loads in lock mode |
100 switching operations |
|
|
Pulse 1bis |
- 100 V for 20 s minimum |
|
|
+ 100 V for 20 s minimum |
EQ/IC 10 test waveform (Pulse 1bis of - 100 V)
EQ/IC 10 test waveform (Pulse 1bis of + 100 V)
EQ/IC 10 - Practical Inductive Load Method Test Layout
EQ/IC 10 - Simulated (Alternate) Load Method Test Arrangement
2. The precautions for implementing the actual inductive load method test are as follows:
Ø The EUT and wiring harness must be placed on an insulating pad with a height of 50mm.
Ø Mode 1: Set the EUT to drive a real inductive load with a mechanical load, taking into account the prevention of overheating, which is necessary and sufficient for the working time, and sufficient intervals to cool down, for example, a cycle of 0,2 Hz and a 20% work cycle.
Ø Mode 2: Set the EUT to drive a locked real inductive load, taking into account the protection against overheating, which is necessary and sufficient for the working time, and sufficient intervals to cool the load, for example, a cycle of 0,2 Hz and a 10% work cycle.
3. Precautions for the implementation of the simulated (standby) load method test are as follows:
Ø The EUT and wiring harness must be placed on an insulating pad with a height of 50mm.
Ø The waveform needs to be calibrated before the test. According to the arrangement above, the waveform calibration is performed in the EUT open circuit state (disconnected), the oscilloscope selects the high-impedance input mode, and the test waveform meets the requirements after debugging at the oscilloscope end. Then proceed to the EUT test.
Ø The EUT needs at least 10 minutes of continuous running time before the test (that is, before the test pulse injection) (also can be understood as the warm-up time)
Ø The waveform generator, sensor and EUT all need to be grounded.
Ø The internal resistance of the waveform generator should be 10Ω.
4. The test report requirements are as follows:
Ø The writing of the test report needs to reflect the following information: test layout, abnormal phenomenon data in the test, test generator characteristics and waveform diagram.
6.2.4. EQ/IC 11: Resistance to impulsive transient
1. This test is intended to check the immunity of the equipment to transients caused by arcing (arcing) occurring at the switchgear and motor contacts. The test waveform, level and test layout are as shown in the figure below, and the main points of the test are as follows:
|
test mode |
Test parameters/levels |
Measured point |
|
positive pulse |
Single duration 20s |
for all wires ; Apply pulses to each wire one by one ( measured one by one ) |
|
Three levels of test voltage: + 400, + 120 or + 80 V |
||
|
Three levels of pulse width: 50 ns, 100 ns, 400 ns |
||
|
Pulse interval: 10 ms – 2 s |
||
|
negative pulse |
Single duration 20s |
for all wires ; Apply pulses to each wire one by one ( measured one by one ) |
|
Three levels of test voltage: - 400, - 120 or - 80 V |
||
|
Three levels of pulse width: 50 ns, 100 ns, 400 ns |
||
|
Pulse interval: 10 ms – 2 s |
|
test |
Pulse amplitude |
|
Pins for connecting unshielded wires |
+400V |
|
-400V |
|
|
Pin to which the shield wire is connected. (One end of the shield is grounded inside the vehicle.) |
+120V |
|
-120V |
|
|
Pin to which the shield wire is connected. (Both ends of the shield are grounded inside the vehicle.) |
+80V |
|
-80V |
EQ/IC 11 Test Level Form
EQ/IC 11 test waveform diagram
EQ/IC 11 Test Layout
|
coupling capacitance ( Applied to the red circle in the above picture) |
Wires for this test |
|
10 nF |
Wires to 12 V power supply (BAT, IGN, ACC) |
|
470pF |
Wires other than above (including 5 V power supply wire) |
Selection of Coupling Capacitor Values
2. The precautions for the implementation steps of waveform calibration are as follows:
Ø Connect the high-impedance input of the oscilloscope (EUT disconnected) to the pulse generator output via a coupling capacitor 10 nF, and set the pulse generator to obtain pulses of the specified positive and negative voltages.
Ø Likewise, set the pulse generator through the coupling capacitor 470 pF.
3. The precautions for the test implementation steps are as follows:
Ø The maximum length of the EUT harness shall not exceed 2m.
Ø Filter for all wires except ground (64µH inductor)
Ø Ground filter (8µH inductor)
Ø The wire length from the filter to the EUT terminal should be a maximum of 200 mm
Ø Pulse generator (output impedance 50Ω) .
Ø The EUT and wiring harness must be placed on an insulating pad with a height of 50mm.
Ø The EUT needs at least 10 minutes of continuous running time before the test (that is, before the test pulse is injected) (it can also be understood as the warm-up time).
Ø All wires need to be tested individually one by one.
4. The test report requirements are as follows:
Ø The writing of the test report needs to reflect the following information: test layout, abnormal phenomenon data in the test, test generator characteristics and calibration waveform diagram.
END