ANNEX 5

Test procedures for the vehicles equipped with electric power train

This annex describes test procedures to demonstrate compliance to the electrical safety requirements of paragraph 5.2.2 of this Regulation.

1. Test setup and equipment If a high voltage disconnect function is used, measurements are to be taken from both sides of the device performing the disconnect function.However, if the high voltage disconnect is integral to the REESS or the energy conversion system and the high-voltage bus of the REESS or the energy conversion system is protected according to protection degree IPXXB following the impact test, measurements may only be taken between the device performing the disconnect function and the electrical loads. The voltmeter used in this test shall measure DC values and have an internal resistance of at least 10 MΩ.

2. The following instructions may be used if voltage is measured. After the impact test, determine the high voltage bus voltages (Ub, U1, U2) (see Figure 1 below). The voltage measurement shall be made not earlier than 10 seconds, but, not later than 60 seconds after the impact. This procedure is not applicable if the test is performed under the condition where the electric power train is not energized.

3. Assessment procedure for low electrical energy Prior to the impact a switch S1 and a known discharge resistor Re is connected in parallel to the relevant capacitance (ref. Figure 2 below). (a) Not earlier than 10 seconds and not later than 60 seconds after the impact the switch S1 shall be closed while the voltage Ub and the current Ie are measured and recorded. The product of the voltage Ub and the current Ie shall be integrated over the period of time, starting from the moment when the switch S1 is closed (tc) until the voltage Ub falls below the high voltage threshold of 60 V DC (th). The resulting integration equals the Total Energy (TE) in joules. (b) When Ub is measured at a point in time between 10 seconds and 60 seconds after the impact and the capacitance of the X-capacitors (Cx) is specified by the manufacturer, Total Energy (TE) shall be calculated according to the following formula: TE = 0,5 × Cx × Ub 2 (c) When U1 and U2 (see Figure 1 above) are measured at a point in time between 10 seconds and 60 seconds after the impact and the capacitances of the Y-capacitors (Cy1, Cy2) are specified by the manufacturer, Total Energy (TEy1, TEy2) shall be calculated according to the following formulas: TEy1 = 0,5 × Cy1 × U1 2 TEy2 = 0,5 × Cy2 × U2 2 This procedure is not applicable if the test is performed under the condition where the electric power train is not energized.

4. Physical protection Following the vehicle impact test any parts surrounding the high voltage components shall be, without the use of tools, opened, disassembled or removed. All remaining surrounding parts shall be considered part of the physical protection. The jointed test finger described in Figure 3 shall be inserted into any gaps or openings of the physical protection with a test force of 10 N ± 10 per cent for electrical safety assessment. If partial or full penetration into the physical protection by the jointed test finger occurs, the jointed test finger shall be placed in every position as specified below. Starting from the straight position, both joints of the test finger shall be rotated progressively through an angle of up to 90° with respect to the axis of the adjoining section of the finger and shall be placed in every possible position. Internal electrical protection barriers are considered part of the enclosure. If appropriate a low-voltage supply (of not less than 40 V and not more than 50 V) in series with a suitable lamp should be connected, between the jointed test finger and high voltage live parts inside the electrical protection barrier or enclosure. Material: metal, except where otherwise specified Linear dimensions in mm. Tolerances on dimensions without specific tolerance: (a) On angles: + 0°0′0″/– 0°0′10″; (b) On linear dimensions: (i) ≤ 25 mm: + 0/– 0,05 mm; (ii) > 25 mm: ± 0,2 mm Tolerances on dimensions without specific tolerance: Both joints shall permit movement in the same plane and the same direction through an angle of 90° with a 0 to + 10° tolerance. The requirements of paragraph 5.2.2.1.3 of this Regulation are met if the jointed test finger described in Figure 3, is unable to contact high voltage live parts. If necessary, a mirror or a fiberscope may be used to inspect whether the jointed test finger touches the high voltage buses. If this requirement is verified by a signal circuit between the jointed test finger and high voltage live parts, the lamp shall not light.

4.1. Test method for measuring electric resistance: (a) Test method using a resistance tester. The resistance tester is connected to the measuring points (typically, the electrical chassis and electro conductive enclosure/electrical protection barrier) and the resistance is measured using a resistance tester that meets the specification that follows: (i) Resistance tester: Measurement current at least 0,2 A; (ii) Resolution: 0,01 Ω or less; (iii) The resistance R shall be less than 0,1 Ω. (b) Test method using DC power supply, voltmeter and ammeter. The DC power supply, voltmeter and ammeter are connected to the measuring points (Typically, electrical chassis and electro conductive enclosure/electrical protection barrier). The voltage of the DC power supply is adjusted so that the current flow becomes at least 0,2 A. The current ‘I’ and the voltage ‘U’ are measured. The resistance ‘R’ is calculated according to the following formula: R = U / I The resistance R shall be less than 0,1 Ω. Note: If lead wires are used for voltage and current measurement, each lead wire shall be independently connected to the electrical protection barrier/enclosure/electrical chassis. Terminal can be common for voltage measurement and current measurement. Example of the test method using DC power supply, voltmeter and ammeter is shown below.

5. Isolation resistance

5.1. General The isolation resistance for each high voltage bus of the vehicle is measured or shall be determined by calculating the measurement values of each part or component unit of a high voltage bus. All measurements for calculating voltage(s) and electrical isolation are made after a minimum of 10 s after the impact.

5.2. Measurement method. The isolation resistance measurement is conducted by selecting an appropriate measurement method from among those listed in paragraphs 5.2.1 to 5.2.2 of this annex, depending on the electrical charge of the live parts or the isolation resistance. The range of the electrical circuit to be measured is clarified in advance, using electrical circuit diagrams. If the high voltage buses are conductively isolated from each other, isolation resistance shall be measured for each electrical circuit. Moreover, modifications necessary for measuring the isolation resistance may be carried out, such as removal of the cover in order to reach the live parts, drawing of measurement lines and change in software. In cases where the measured values are not stable due to the operation of the on-board isolation resistance monitoring system, necessary modifications for conducting the measurement may be carried out by stopping the operation of the device concerned or by removing it. Furthermore, when the device is removed, a set of drawings will be used to prove that the isolation resistance between the live parts and the electrical chassis remains unchanged. These modifications shall not influence the test results. Utmost care shall be exercised to avoid short circuit and electric shock since this confirmation might require direct operations of the high-voltage circuit.

5.2.1. Measurement method using DC voltage from external sources.

5.2.1.1. Measurement instrument. An isolation resistance test instrument capable of applying a DC voltage higher than the working voltage of the high voltage bus shall be used.

5.2.1.2. Measurement method. An isolation resistance test instrument is connected between the live parts and the electrical chassis. The isolation resistance is subsequently measured by applying a DC voltage at least half of the working voltage of the high voltage bus. If the system has several voltage ranges (e.g. because of boost converter) in conductively connected circuit and some of the components cannot withstand the working voltage of the entire circuit, the isolation resistance between those components and the electrical chassis can be measured separately by applying at least half of their own working voltage with those components disconnected.

5.2.2. Measurement method using the vehicle's own REESS as DC voltage source.

5.2.2.1. Test vehicle conditions. The high voltage-bus is energized by the vehicle's own REESS and/or energy conversion system and the voltage level of the REESS and/or energy conversion system throughout the test shall be at least the nominal operating voltage as specified by the vehicle manufacturer.

5.2.2.2. Measurement method.

5.2.2.2.1. First step. The voltage is measured as shown in Figure 1 and the high voltage bus voltage (Ub) is recorded.

5.2.2.2.2. Second step. The voltage (U1) between the negative side of the high voltage bus and the electrical chassis is measured and recorded (see Figure 1).

5.2.2.2.3. Third step. The voltage (U2) between the positive side of the high voltage bus and the electrical chassis is measured and recorded (see Figure 1).

5.2.2.2.4. Fourth step. If U1 is greater than or equal to U2, a standard known resistance (R0) is inserted between the negative side of the high voltage bus and the electrical chassis. With R0 installed, the voltage (U1') between the negative side of the high voltage bus and the electrical chassis is measured (see Figure 5). The electrical isolation (Ri) is calculated according to the following formula: Ri = R0*Ub*(1/U1' – 1/U1) If U2 is greater than U1, insert a standard known resistance (R0) between the positive side of the high voltage bus and the electrical chassis. With R0 installed, measure the voltage (U2’) between the positive side of the high voltage bus and the electrical chassis (see Figure 6). The electrical isolation (Ri) is calculated according to the following formula: Ri = R0*Ub*(1/U2' – 1/U2)

5.2.2.2.5. Fifth step. The electrical isolation value Ri (in Ω) divided by the working voltage of the high voltage bus (in V) results in the isolation resistance (in Ω/V). Note: The standard known resistance R 0 (in Ω) should be the value of the minimum required isolation resistance (Ω/V) multiplied by the working voltage (V) of the vehicle plus/minus 20 per cent. R 0 is not required to be precisely this value since the equations are valid for any R o ; however, a R 0 value in this range should provide a good resolution for the voltage measurements.

6. Electrolyte leakage An appropriate coating, if necessary, may be applied to the physical protection (casing) in order to confirm if there is any electrolyte leakage from the REESS after the impact test.