JB/T 11880.6-2014Diesel engines - Selective catalytic reduction (SCR) systems - Part 6: Electronic control units (English PDF)

5.4 Protection performance

5.4.3 Waterproof performance

DCU should adopt the IPX9 requirements in ISO 20653 for waterproof test.

5.5 Electrical performance

5.5.1 Overvoltage performance

The DCU shall be subjected to an overvoltage test, to confirm its ability to not be damaged under the power supply overvoltage condition. The test shall be carried out in accordance with the provisions of 6.4.1.

12 V system: Test at a temperature of (Tmax - 25 °C); the functional status of the DCU shall reach Class B as specified in Appendix C.

24 V system: Test at a temperature of (Tmax - 25 °C); the functional status of DCU must reach the class B as specified in Appendix C.

5.5.2 Slow drop or ramp of supply voltage

The DCU carries out the power supply voltage drop or ramp test according to 6.4.2. Within the power supply voltage range as specified in Table 2, the functional status shall reach the class A as specified in Appendix C; outside the power supply voltage range, the functional status shall reach the class C as specified Appendix C.

5.5.3 Reset performance for voltage dip

To verify the reset performance of the DCU under constant voltage dips, it is suitable for devices with reset functions (for example, devices equipped with one or more microcontrollers).

The DCU shall be tested in accordance with the provisions of 6.4.3. After the test, the functional status of the DCU shall reach the class C as specified in Appendix C.

5.5.4 Short circuit protection

The DCU shall be tested according to the provisions of 6.4.4. After the test, the functional status of the DCU shall reach the class C as specified in Appendix C.

5.5.5 Battery reverse protection

The DCU shall be tested in accordance with the provisions of 6.4.5. It shall be able to withstand the power supply polarity reversal test of 60 s ± 6 s without damage. clearly visible; no salt water shall enter the DCU housing; the functional status of the DCU shall reach the class A as specified in Appendix C.

5.12 Resistance to industrial solvents

DCU should be subject to industrial solvent resistance test to determine the ability of DCU to withstand industrial solvents. The types of solvents are recommended to use more than 3 kinds of solvents such as brake fluid, antifreeze, engine oil, engine diesel, wheel cleaner, glass cleaner.

Manufacturers and users can negotiate to add additional tests; during selection of product materials, it shall consider the resistance to chemical reagents as early as possible.

The DCU undergoes the test in a non-working state. After the specified time of industrial solvent soaking, air-drying, the corresponding number of cycles, there shall be no changes that reduce normal functions (for example, sealing function); signs and labels shall be kept clearly visible; the functional status of the DCU shall reach the class C as specified in Appendix C.

5.13 Surface protection performance

5.13.1 Coating and chemical treatment layer

The coating and chemical treatment layer of the metal parts of the product shall meet the requirements of QC/T 625.

5.13.2 Painting layer

5.13.2.1 Appearance of the painting layer: The external painting layer of the product shall be uniform, free of bubbles, blanks, accumulation, overflow.

5.13.2.2 The adhesion of the painting layer: The painting layer of the product shall be firmly bonded to the surface of the covered object; the painting layer shall not fall off after the grid method test.

5.13.2.3 Temperature resistance of the painting layer: After the painting layer of the product is subjected to the high-temperature test specified in this part, there shall be no shrinkage or delamination.

5.13.2.4 Corrosion resistance of the painting layer: The painting layer of the product is not allowed to rust after undergoing a 48-hour salt spray resistance test.

5.13.3 Other

deviation occurs; record this current in the test report.

6.7 Radiation immunity test

The radiated immunity test of the product shall meet the requirements of ISO 11452-2, as follows:

a) When the test frequency is greater than 30 MHz, use the horizontal and vertical polarization; when the test frequency is less than or equal to 30 MHz, it only uses vertical polarization.

b) When the test frequency is greater than or equal to 1000 MHz, the DCU shall be tested in at least three perpendicular directions.

c) In all tests, the frequency jump point is executed according to strict requirements. The monitoring of electrical signals shall use high impedance connections to prevent coupling to the walls of the darkroom.

The analog load or signal generator shall be placed in a dark room.

6.8 Magnetic field immunity test

The magnetic field immunity test shall meet the requirements of ISO 11452-1 and ISO 11452-8.

Before performing the DCU test, use the prescribed procedures to calibrate the test equipment. The configuration of the test device shall help exposing the DCU directly to the magnetic field of the magnetic field strength specified in the test plan. It shall also help exposing the magnetic sensor that may be connected to the DCU to the magnetic field. This can be achieved by a magnetic radiation coil or Helmholtz coil with a diameter of 120 mm. The distance between the test bench or any part of the ground plane and the radiation ring or Helmholtz coil shall not be less than 200 mm.

The test shall be performed in three orthogonal directions. If an abnormality occurs, the magnetic field strength shall be reduced until the abnormal phenomenon disappears; then the magnetic field strength shall be gradually increased until the abnormality occurs again. The magnetic field strength at this time is used as the threshold and the explained in the experiment report.

6.9 Transient immunity test along the power line

The transient immunity test of the product along the power line complies with the requirements of ISO 7637-1 and ISO 7637-2.

6.12 Radiation emission test

The radiation emission test shall be carried out in accordance with GB/T 18655.

6.13 Conducted emission test

Conducted emission test shall be carried out in accordance with GB/T 18655.

6.14 Conducted transient emission test

The conducted transient emission test shall meet the requirements in ISO 7637-2, as follows:

a) Turn off the external switch and power up the DCU. Verify that the functions of the DCU are operating correctly. Set the trigger level of the oscilloscope to 80% of the set limit. When setting the time base value, adjust the oscilloscope's sampling rate to the highest level available for the selectable time base.

b) For all component categories with switching power supply circuits, measure and record the peak instantaneous voltage when the DCU is turned off and on 10 times (10 times in each case).

6.15 High-and low-temperature resistance test

6.15.1 Low-temperature resistance test

Carry out the test in accordance with the corresponding test method in the test Ad (low-temperature test of heat dissipation sample's gradual temperature gradient - The test sample is energized after the temperature starts to stabilize) in GB/T 2423.1.

DCU is subject to a 24-hour low-temperature storage test under the low-temperature condition of -40 °C according to the operating mode 1.1 as specified in Appendix D. Power on the DCU, carry out a 24-hour low-temperature operating test according to the operating mode 3.2 as specified in Appendix D. Check the DCU to see whether its function meets the requirements.

6.15.2 High-temperature resistance test

Carry out the test in accordance with the corresponding test method in the test Bd (high-temperature test of heat dissipation sample's gradual temperature gradient - The test sample is not-energized during the regulating period of the Place the DCU full of reagents at the specified temperature for 24 hours and under the specified time and temperature sufficient to affect the properties of the material, the defined resistance performance will not change. The model of chemical reagents used in the test shall be negotiated between the supplier and the buyer.

A contaminant is used for one sample. Coat the surface of the uncontaminated DCU with reagents. Excessive reagents are allowed to drip from the DCU during the test.

6.22 Surface protection inspection

6.22.1 Inspection of metal plating and chemical treatment layer

The metal plating and chemical treatment layer of DCU shall be inspected according to the method as specified in QC/T 625.

6.22.2 Inspection of paint layer

6.22.2.1 Visual inspection of paint layer

The appearance quality of the paint layer of DCU is inspected by visual observation.

6.22.2.2 Adhesion inspection of paint layer

It can directly use the grid method to form nine squares on the surface paint layer of the three samples of the fully dried product or sample (10 cm x 15 cm), by using blade to make four horizontal and vertical lines, at a spacing of 1 mm, to make inspection. The paint layer in the grid shall be free of layering.

6.22.2.4 Salt spray resistance test of paint layer

It is carried out simultaneously with the salt spray resistance test as specified in 6.20. Observe whether the paint layer of the product is corroded after 48 hours of the test.

6.22.2.5 Other protective inspections

Check with naked eyes.

8.1 Marking

8.1.1 Product mark

8.1.1.1 The nameplate of the product shall be fixed on the obvious part of the DCU; its basic contents include:

a) Product name and trademark;

b) Product model;

c) Production date (or serial number) or production batch number;

d) The main technical parameters of the product;

e) The name of the manufacturer.

Items can be added according to specific conditions, such as product implementation standard number, quality grade mark, warning signs or warning instructions in Chinese, product barcodes, etc., or according to user requirements.

8.1.1.2 The nameplate of the product shall meet the requirements of GB/T 13306.

8.1.2 Packaging mark

The basic content of the packaging mark includes:

a) The content of the product mark related to the shipment: product name and trademark, product model, specification;

b) The name, full address, postal code and telephone number of the manufacturer;

c) Production date (or serial number) or production batch number;

d) Product's implemented standard number;

e) Packaging, storage and transportation pictorial signs (in accordance with GB 191);

f) The text of the transportation operation: the overall dimensions of the packaging carton (length x width x height); the quantity of products in each

16.22.2.3 Temperature resistance test of the paint layer

It is carried out simultaneously with the high-temperature resistance test as specified in 6.15.2.

A.1 Address

In the CAN bus, the source address of DCU is 0x3D. The address of EECU is 0x00; the address of NOx sensor downstream of the catalytic converter is 0x52.

A.2 Independent dosing control unit

A.2.1 Send message: DM1, DM2, DM3, DM4, DM11, DM12, TI1, ACK, EEC3

A.2.2 Receive message: AT10G1, PGNRQ

A.2.3 In addition to the above basic messages, the communication messages between the DCU and the metering pump are determined by the metering pump manufacturer.

A.3 Integration

of dosing control unit and metering pump dosing control unit

A.3.1 Send message: see A.2.1

A.3.2 Receive message: see A.2.2

A.4 Integration of dosing control unit in the EECU

A.4.1 Send message: DM1, DM2, DM3, DM4, DM11, DM12, ACK, TI1, EEC3

A.4.2 Receive message: PGNRQ, AT10G1, EEC1, AMB, ENGTEMP, INCON

A.4.3 In addition to the basic messages mentioned above, the communication messages between EECU and the metering pump are determined by the manufacturer of the metering pump.

B.1 The SCR system's OBD needs to monitor the failure of the following components and functions

B.1.1 Nitrogen oxide sensor: It shall monitor its power supply, electrical failure, signal range, signal deviation and signal credibility, deviation of upstream and downstream nitrogen and oxygen concentration.

B.1.2 Urea solution supply pump: The voltage range of the pressure sensor, the pressure range of the urea pump, the electrical failure of the urea pump motor, the deviation of the urea pump's motor speed, the effectiveness of the temperature duty cycle of urea pump heater, the effectiveness of temperature measurement of the urea pump, the effectiveness of the temperature duty cycle of urea pump, the electrical failure of the urea reversing valve's actuator (if applicable), the reliability of the reversing valve (if applicable), the reliability of the heating of the urea pump, etc.

B.1.3 Urea solution level sensor: It shall monitor the electrical failure, the urea solution level, the reliability of the urea consumption.

B.1.4 Urea temperature sensor: It shall monitor the electrical failure, the urea solution level, the overheating of urea tank.

B.1.5 SCR exhaust temperature sensor: It shall monitor the electrical failure, signal credibility.

B.1.6 Urea nozzle: It shall monitor its current and electrical failure (if applicable).

B.1.7 Urea heating device: It shall monitor the electrical failure, reliability of the heating circuit.

B.1.8 Air valve: It shall monitor air failure, atmospheric pressure (if applicable).

B.1.9 Pressure tube: It shall monitor the pressure range, reliability of pressure (if applicable).

B.1.10 Nitrogen and oxygen emission monitoring: It shall monitor the failure where the nitrogen and oxygen emission exceeds 7.0 g/ (kW · h). According to the provisions of GB 17691-2005, the national IV emission shall monitor the failure where the nitrogen and oxygen emission exceeds 5.0 g/ (kW · h); the […]