Division 7.5 General test sequence

To measure engine emissions the following steps have to be performed:

1. (a)

   The engine test speeds and test loads have to be defined for the engine to be tested by measuring the max torque (for constant-speed engines) or max torque curve (for variable-speed engines) as function of the engine speed;

2. (b)

   Normalized test cycles have to be denormalized with the torque (for constant-speed engines) or speeds and torques (for variable-speed engines) found in the previous point 7.5(a);

3. (c)

   The engine, equipment, and measurement instruments shall be prepared for the following emission test or test series (cold-start run and hot-start run) in advance;

4. (d)

   Pre-test procedures shall be performed to verify proper operation of certain equipment and analyzers. All analysers have to be calibrated. All pre-test data shall be recorded;

5. (e)

   The engine shall be started (NRTC) or kept running (steady-state cycles and LSI-NRTC) at the beginning of the test cycle and the sampling systems shall be started at the same time;

6. (f)

   Emissions and other required parameters shall be measured or recorded during sampling time (for NRTC, LSI-NRTC and RMC throughout the whole test cycle);

7. (g)

   Post-test procedures shall be performed to verify proper operation of certain equipment and analyzers;

8. (h)

   F1PM filter(s) shall be pre-conditioned, weighed (empty weight), loaded, re-conditioned, again weighed (loaded weight) and then samples shall be evaluated in accordance with the pre-test (point 7.3.1.6) and post-test (point 7.3.2.2) procedures;

9. (i)

   Emission test results shall be evaluated.

Figure 6.4 gives an overview about the procedures needed to conduct NRMM test cycles with measuring exhaust engine emissions.