Document ID: chunk:federal_register_of_legislation:F2023L01526:body:0:p45
Version: federal_register_of_legislation:F2023L01526
Segment Type: other
Provision Reference: 
Character Range: 126986–129995

temperature conditioning system of the REESS is neither damaged nor presenting a capacity defect

    Figure 1
    Determination of hydrogen emissions during the charge procedures of the REESS

       4. Test equipment for hydrogen emission test

       4.1. Chassis dynamometer

        The chassis dynamometer shall meet the requirements of the 06 series of amendments to Regulation No. 83.

       4.2. Hydrogen emission measurement enclosure

       The hydrogen emission measurement enclosure shall be a gas-tight measuring chamber able to contain the vehicle/REESS under test. The vehicle/REESS shall be accessible from all sides and the enclosure when sealed shall be gas-tight in accordance with Appendix 1 to this annex. The inner surface of the enclosure shall be impermeable and non‑reactive to hydrogen.

       The temperature conditioning system shall be capable of controlling the internal enclosure air temperature to follow the prescribed temperature throughout the test, with an average tolerance of ±2 K over the duration of the test.

       To accommodate the volume changes due to enclosure hydrogen emissions, either a variable-volume or another test equipment may be used. The variable-volume enclosure expands and contracts in response to the hydrogen emissions in the enclosure. Two potential means of accommodating the internal volume changes are movable panels, or a bellows design, in which impermeable bags inside the enclosure expand and contract in response to internal pressure changes by exchanging air from outside the enclosure. Any design for volume accommodation shall maintain the integrity of the enclosure as specified in Annex 8, Appendix 1.

       Any method of volume accommodation shall limit the differential between the enclosure internal pressure and the barometric pressure to a maximum value of ±5hPa.

       The enclosure shall be capable of latching to a fixed volume. A variable volume enclosure shall be capable of accommodating a change from its "nominal volume" (see Annex 8, Appendix 1, paragraph 2.1.1.), taking into account hydrogen emissions during testing.

       4.3. Analytical systems

       4.3.1. Hydrogen analyser

       4.3.1.1. The atmosphere within the chamber is monitored using a hydrogen analyser (electrochemical detector type) or a chromatograph with thermal conductivity detection. Sample gas shall be drawn from the mid-point of one side-wall or roof of the chamber and any bypass flow shall be returned to the enclosure, preferably to a point immediately downstream of the mixing fan.

       4.3.1.2. The hydrogen analyser shall have a response time to 90 per cent of final reading of less than 10 seconds. Its stability shall be better than 2 per cent of full scale at zero and at 80 per cent ± 20 per cent of full scale, over a 15-minute period for all operational ranges.

       4.3.1.3. The repeatability of the analyser expressed as one standard deviation shall be better than 1 per cent of full scale, at zero and at