6.3.2 Engine parameter to be measured and recorded
Table 6 lists the engine parameters that shall be measured and recorded during on-board verification procedures.
Table 6. Engine parameters to be measured and recorded
6.3.3 Brake power
6.3.3.1 The point regarding the ability to obtain the required data during on-board NOx testing in particularly relevant so brake power. Although the case of directly coupled gearboxes is considered its chapter 5, the engines, an may be presented on board, could in many applications, be arranged such that the measurements of torque (as obtained from a specially installed strain gauge) may not be possible due to the absence of a clear shaft. Principal in this group would be generators, but engines may also be coupled to pumps. hydraulic units, compressors, etc.
6.3.3.2 The engines driving such machinery would typically have been tested against a water brake at the manufacture stage prior to the permanent connection of the power consuming unit when installed on board. For generators this should not pose a problem to use voltage and amperage measurements
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together with a manufacturer's declared generator efficiency. For propeller law governed equipment, a declared speed power curve may be applied together with ensured capability to measure engine speed, either from the free end or by ratio of, for example, the camshaft speed.
6.3.4 Test fuels
6.3.4.1 Generally all emission measurements shall be carried out with the engine running on marine diesel fuel oil of an ISO 8217, 1996, DM-grade.
6.3.4.2 To avoid an unacceptable burden to the shipowner, the measurements for confirmation tests or re-surveys may, based on the recommendation of the engine manufacturer and the approval of the Administration, be allowed with an engine running on heavy fuel oil of an ISO 8217. 1996, RM-grade. In such a case the fuel bound nitrogen and the ignition quality of the fuel may have an influence on the NOx emissions of the engine.
6.3.5 Sampling for gaseous emissions
6.3.5.1 The general requirements described in 5.9.3 shall be applied for on-board measurements as well.
6.3.5.2 The installation on board of all engines shall be such, that these tests may be performed safely and with minimal interference so the engine. Adequate arrangements for the sampling of the exhaust gas and the ability to obtain the required data shall be provided on board a ship. The uptakes of all engines shall be fitted with an accessible standard sampling point.
6.3.6 Measurement equipment and data to be measured
The emission of gaseous pollutants shall be measured by the methods described in chapter 5.
6.3.7 Permissible deviation of instruments for engine related parameters and other essential parameters
Tables 3 and 4 contained in paragraph 1.3.2 of appendix 6 of this Code list the permissible deviation of instruments to be used in the measurement of engine-related parameters and other essential parameters during on-board verification procedures.
6.3.8 Determination of the gaseous components
The analytical measuring equipment and the methods described in chapter 5 shall be applied.
6.3.9 Test cycles
6.3.9.1 Test cycles used on board shall conform to the applicable test cycles specified in 3.2.
6.3.9.2 Engine operation on board under a test cycle specified in 3.2 may not always be possible, but the test procedure shall, based on the recommendation of the engine manufacturer and approval by the Administration, be as clone as possible to the procedure defined in 3.2. Therefore, values measured in this case may not be directly comparable with test bed results because measured values are very much dependent on the test cycles.
