10.11.2022
EN
Official Journal of the European Union
L 290/583
6.5.9.2.
The enclosure shall be purged for several minutes immediately before the test until a stable background is obtained.
The chamber mixing fan(s) shall also be switched on at this time.
6.5.9.3.
The test vehicle, with the powertrain shut off and the test vehicle windows and luggage compartment(s) opened, shall be moved into the measuring chamber.
The mixing fan(s) shall be adjusted in such a way as to maintain a minimum air circulation speed of 8 km/h under the fuel tank of the test vehicle.
6.5.9.4.
The hydrocarbon analyser shall be zeroed and spanned immediately before the test.
6.5.9.5.
The enclosure doors shall be closed and sealed gas-tight.
6.5.9.6.
Within 10 minutes of closing and sealing the doors, the hydrocarbon concentration, temperature and barometric pressure shall be measured to give initial readings of hydrocarbon concentration in the enclosure (CHCi), barometric pressure (Pi) and ambient chamber temperature (Ti) for the diurnal testing.
Tstart = 0 starts at this time.
6.5.9.7.
The hydrocarbon analyser shall be zeroed and spanned immediately before the end of each emission sampling period.
6.5.9.8.
The end of the first and second emission sampling period shall occur at 24 hours ± 6 minutes and 48 hours ± 6 minutes, respectively, after the beginning of the initial sampling, as specified in paragraph 6.5.9.6. of this annex.
The elapsed time shall be recorded.
At the end of each emission sampling period, the hydrocarbon concentration, temperature and barometric pressure shall be measured and used to calculate the diurnal test results using the equation in paragraph 7.1. of this annex.
The result obtained from the first 24 hours shall be recorded as MD1.
The result obtained from the second 24 hours shall be recorded as MD2.
6.6.
Continuous test procedure for sealed fuel tank systems
6.6.1.
In the case that the fuel tank relief pressure is greater than or equal to 30 kPa
6.6.1.1.
The test shall be performed as described in paragraphs 6.5.1. to 6.5.3. inclusive of this annex.
6.6.1.2.
Fuel drain and refill Within one hour after the preconditioning drive, the fuel tank of the vehicle shall be emptied.
This shall be done so as not to abnormally purge or abnormally load the evaporative control devices fitted to the vehicle.
Removal of the fuel cap is normally sufficient to achieve this, otherwise the carbon canister shall be disconnected.
The fuel tank shall be refilled with reference fuel at a temperature of 18 °C ± 2 °C to 15 ± 2 per cent of the tank's nominal capacity.
The operations described in paragraphs 6.6.1.3., 6.6.1.4. and 6.6.1.5. of this annex shall be completed within a total of 36 hours and for the operations described in paragraphs 6.6.1.4. and 6.6.1.5. the vehicle shall not be exposed to temperatures above 25 °C.
6.6.1.3.
Soak Within 5 minutes after completing fuel drain and refill, the vehicle shall be soaked for stabilisation for at least 6 hours at an ambient temperature of 20 °C ± 2 °C.
6.6.1.4.
Fuel tank depressurisation The tank pressure shall be subsequently released so as not to abnormally raise the inside pressure of the fuel tank.
This may be done by opening the fuel cap of the vehicle.
Regardless of the method of depress­ urisation, the vehicle shall be returned to its original condition within 1 minute.
6.6.1.5.
Carbon canister loading and purge The carbon canister aged in accordance with the sequence described in paragraph 5.1. to 5.1.3.1.3. inclusive of this annex shall be loaded to 2 gram breakthrough according to the procedure described in paragraphs 6.5.5.4. to 6.5.5.4.5. inclusive to this annex, and shall be subsequently purged with 25 ± 5 litres per minute with emission laboratory air.
The volume of purge air shall not exceed the volume determined in accordance with the requirements of paragraph 6.6.1.5.1.
This loading and purging can be done either (a) using an on-board carbon canister at a temperature of 20 °C or optionally 23 °C, or (b) by disconnecting the carbon canister.
In both cases, no further relief of the tank pressure is allowed.