Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:13:p8
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 13 (pt 8/56)
Character Range: 316767–319547

and warmed up in accordance with paragraph 7.4.1. After warm-up, the engine and sampling system shall be preconditioned by operating the engine at mode 9 (see paragraph 7.2.2., Table 1) for a minimum of 10 minutes while simultaneously operating the dilution system. Dummy particulate emissions samples may be collected. Those sample filters need not be stabilized or weighed, and may be discarded. Flow rates shall be set at the approximate flow rates selected for testing. The engine shall be shut off after preconditioning.

7.7.2. Engine starting

 5  1 minutes after completion of preconditioning at mode 9 as described in paragraph 7.7.1., the engine shall be started according to the manufacturer's recommended starting procedure in the owner's manual, using either a production starter motor or the dynamometer in accordance with paragraph 7.6.2.

7.7.3. Test sequence

 The test sequence shall commence after the engine is running and within one minute after engine operation is controlled to match the first mode of the cycle (idle).

 The WHSC shall be performed according to the order of test modes listed in Table 1 of paragraph 7.2.2.

7.7.4. Collection of emission relevant data

 At the start of the test sequence, the measuring equipment shall be started, simultaneously:
(a) Start collecting or analyzing diluent, if a full flow dilution system is used;
(b) Start collecting or analyzing raw or diluted exhaust gas, depending on the method used;
(c) Start measuring the amount of diluted exhaust gas and the required temperatures and pressures;
(d) Start recording the exhaust gas mass flow rate, if raw exhaust gas analysis is used;
(e) Start recording the feedback data of speed and torque of the dynamometer.

 If raw exhaust measurement is used, the emission concentrations ((NM)HC, CO and NOx) and the exhaust gas mass flow rate shall be measured continuously and stored with at least 2 Hz on a computer system. All other data may be recorded with a sample rate of at least 1 Hz. For analogue analyzers the response shall be recorded, and the calibration data may be applied online or offline during the data evaluation.

 If a full flow dilution system is used, HC and NOx shall be measured continuously in the dilution tunnel with a frequency of at least 2 Hz. The average concentrations shall be determined by integrating the analyzer signals over the test cycle. The system response time shall be no greater than 20 seconds, and shall be coordinated with CVS flow fluctuations and sampling time/test cycle offsets, if necessary. CO, CO2, and NMHC may be determined by integration of continuous measurement signals or by analyzing the concentrations in the sample bag, collected over the cycle. The concentrations of the gaseous pollutants in the diluent