GB 38032-2020Electric buses safety requirements (English PDF)

4.2 Requirements for waterproof and dustproof performance

4.2.1 Vehicle wading requirements Carry out the vehicle wading test according to the test method specified in 5.1.1. Within 10 min after the test is completed, the insulation resistance of the vehicle shall be greater than 1 MOmega.

4.2.2 Requirements for degrees of protection provided by Class B voltage components

4.2.3 Vehicle soaking requirements Carry out the vehicle soaking test according to the test method specified in 5.1.3.Within 2 h after the test is completed, the vehicle shall not be fired or exploded.

4.4 Safety requirements for rechargeable energy storage system

4.4.1 Thermal runaway requirements for the minimum management unit of battery system Carry out the thermal runaway test for the minimum management unit of battery system according to the test method specified in 5.3.1.The test object shall not be fired or exploded.

4.4.2 Flame retardant requirements for materials of parts in rechargeable energy storage system Except for secondary cells, other non-metallic parts in the rechargeable energy storage system are subjected to the flame retardant test of the materials of parts in the rechargeable energy storage system according to the test method specified in 5.3.2, which shall meet the following flame retardant requirements.

4.4.4 Requirements for disconnecting devices The rechargeable energy storage system shall be equipped with fuses and manual maintenance switches.

4.4.5 Requirements for pressure relief devices The rechargeable energy storage system shall be equipped with directional pressure relief and pressure balancing devices, and the pressure relief pressure shall not exceed 50 kPa.

4.4.6 Abnormal alarm requirements The rechargeable energy storage system shall provide a thermal event alarm signal 5 min before thermal diffusion due to thermal runaway of a single battery, which in turn causes a danger in the passenger cabin.

4.6 Charging safety requirements

4.6.1 Safety requirements for charging interfaces When the vehicle is equipped with multiple charging interfaces, the charging interface that does not perform charging shall be electrically neutral.

4.7 Safety requirements after vehicle crash and rollover

4.7.1 Safety requirements after vehicle crash If there is a rechargeable energy storage system of which the lowest point is not more than 1 m above the ground (the vehicle is at no-load state), the crash test shall be carried out according to the test method specified in 5.5.1.

4.7.3 Exemption clauses for vehicle crash and rollover tests When a vehicle model that requires the assessment of vehicle crash safety requirements meets one of the following two conditions, it is deemed to meet the requirements of 4.7.1.

5.1 Waterproof and dustproof

5.1.1 Vehicle wading test The vehicle shall travel 500 m at a speed of 5 km/h ~ 10 km/h in a 300 mm deep pool for 3 min ~ 6 min. If the length of the pool is less than 500 m, the test shall be repeated so that the accumulative wading length is not less than 500 m. The total test time, including when the vehicle is outside the pool, shall be less than 10 min.

5.1.3 Vehicle soaking test The vehicle is soaked in a 500mm deep water pool for 24 h with Class A and B voltage circuits disconnected.

5.2 Fireproof performance

5.2.1 Flame retardant performance test of Class B voltage components The horizontal burning and vertical burning shall be tested according to the provisions of GB/T 2408-2008.

5.2.2 Test of flame retardant and thermal insulation performance between rechargeable energy storage system (or installation cabin) and passenger cabin

5.3 Rechargeable energy storage system safety

5.3.1 Thermal runaway test of minimum management unit of battery system Carry out the thermal runaway test according to the provisions of Annex A.

5.3.2 Flame retardant test of materials of components in rechargeable energy storage system The horizontal burning and vertical burning shall be tested according to the provisions of GB/T 2408-2008.

5.4 Functional safety protection The manufacturer provides specific program descriptions according to the functional protection requirements specified in 4.4.3, 4.4.4, 4.4.5, 4.5, and 4.6. The testing organization tests and verifies on the parts or the actual vehicle according to the descriptions, and carries out the compliance judgment.