The gaseous pollutant emissions to be measured and recorded during the in-service monitoring test are: carbon monoxide (CO), total hydrocarbons (HC) and nitrogen oxides (NOx). Additionally, carbon dioxide (CO2) shall be measured to enable the calculation procedures described in Appendix 5.
The parameters set out in the Table shall be measured and recorded during the in-service monitoring test:
Test parameters
| a Measured or corrected to a wet basis. | ||
| b Direct measurement of exhaust mass flow shall be used unless one of the following is applicable: (a) the exhaust system installed in the non-road mobile machinery results in dilution of the exhaust by air upstream of the location where an EFM could be installed. In this case the exhaust sample shall be taken upstream of the point of dilution; or, (b) the exhaust system installed in the non-road mobile machinery diverts a portion of the exhaust to another part of the non-road mobile machinery (e.g. for heating) upstream of the location where an EFM could be installed. In these cases, where the manufacturer is able to provide robust evidence to the approval authority of the correlation between the fuel mass flow estimated by the ECU and the fuel mass flow measured on the engine dynamometer test bench, the EFM may be omitted and indirect exhaust flow measurements (from fuel and intake air flows or fuel flow and carbon balance) may be applied. | ||
| c Use the ambient temperature sensor or an intake air temperature sensor. Use of an intake air temperature sensor shall comply with the requirements set out in the second paragraph of point 5.1. | ||
| d The recorded value shall be either (a) the net torque; or (b) the net torque calculated from the actual engine percent torque, the friction torque and the reference torque, according to standards set out in point 2.1.1 of Appendix 7. The basis for the net torque shall be uncorrected net torque delivered by the engine inclusive of the equipment and auxiliaries to be included for an emissions test in accordance with Appendix 2 of Annex VI to Delegated Regulation (EU) 2017/654. | ||
| Parameter | Unit | Source |
|---|---|---|
| HC concentrationa | ppm | Gas analyser |
| CO concentrationa | ppm | Gas analyser |
| NOx concentrationa | ppm | Gas analyser |
| CO2 concentrationa | ppm | Gas analyser |
| Exhaust mass flowb | kg/h | EFM |
| Exhaust temperature | °K | EFM or ECU or Sensor |
| Ambient temperaturec | °K | Sensor |
| Ambient pressure | kPa | Sensor |
| Relative humidity | % | Sensor |
| Engine torqued | Nm | ECU or Sensor |
| Engine speed | rpm | ECU or Sensor |
| Engine fuel flow | g/s | ECU or Sensor |
| Engine coolant temperature | °K | ECU or Sensor |
| Engine intake air temperaturec | °K | ECU or Sensor |
| Non-road mobile machinery latitude | degree | GPS (optional) |
| Non-road mobile machinery longitude | degree | GPS (optional) |
The test duration, comprising all operating sequences and only including valid data, shall be long enough to complete between five and seven times the work performed during the NRTC or to produce between five and seven times the CO2 reference mass in kg/cycle from the NRTC.
The preparation of the non-road mobile machinery shall comprise at least the following:
the check of the engine: any identified problems, once solved, shall be recorded and presented to the approval authority;
the replacement of the oil, fuel and reagent, if any;
demonstration of the availability of the ECU data stream information, according to the requirements set out in point 2 of Appendix 7.
In any case, the installation shall comply with the locally applicable safety regulations and insurance requirements and shall follow the instructions issued by the PEMS, measurement instruments, transfer line and sampling probe manufacturer.
The electrical power supply of the PEMS shall, be provided by an external power supply unit.
As far as possible, the measurement instruments other than the EFM shall be installed in a location subject to minimal:
ambient temperature changes;
ambient pressure changes;
electromagnetic radiation;
mechanical shock and vibration;
ambient hydrocarbons — if using a FID analyser that uses ambient air as FID burner air.
The installation of the EFM shall not increase the backpressure beyond the value recommended by the manufacturer.
The transfer line shall be properly insulated at the connection points (sampling probe and back of the measurement instruments).
The data logger shall be connected with the engine ECU to record the engine parameters listed in Table 1 of Appendix 7, and, where applicable, the engine parameters listed in Table 2 of Appendix 7.
The antenna should be mounted at the highest possible location, without risking interference with any obstructions encountered during in-use operation.
The ambient temperature shall be measured at the beginning of the test and also at the end of the test within a reasonable distance from the non-road mobile machinery. It is allowed to use the CAN signal for intake air temperature (temperature experienced by the engine).
If an intake air temperature sensor is used to estimate the ambient temperature the recorded ambient temperature shall be the intake air temperature adjusted by the applicable nominal offset between ambient and intake air temperature as specified by the manufacturer.
The measurement instruments shall be warmed up and stabilised until pressures, temperatures and flows have reached their operating set points, according to the instructions issued by the measurement instrument/PEMS manufacturer.
To prevent system contamination, the transfer line shall be purged until sampling begins, according to the instructions issued by the transfer line/PEMS manufacturer.
The transfer line shall be heated to 190 °C (+/– 10 °C) before starting the test to avoid the presence of cold spots that could lead to a contamination of the sample by condensed hydrocarbons.
The zero and span calibration and the linearity checks of the gas analysers shall be performed using the analytical gases set out in point 2.1.3 of Appendix 1.
The EFM shall be purged at the pressure transducer connections in accordance with the instructions issued by the PEMS or EFM manufacturer. This procedure shall remove condensation and diesel particulate matter from the pressure lines and the associated flow tube pressure measurement ports.
Gaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall start prior to starting the engine.
Gaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall continue throughout the normal in-use operation of the engine.
The engine may be stopped and started, but the gaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall continue throughout the entire in-service monitoring test.
At the end of the in-service monitoring test, sufficient time shall be given to the measurement instruments and data logger to allow their response times to elapse. The engine may be shut down before or after data logging is stopped.
The valid measured data for the gaseous pollutant emissions calculations shall be determined in accordance with Appendix 4. Point 6.4.2 shall apply to those calculations.
Cold start gaseous pollutant emissions measured data shall be removed for the gaseous pollutant emissions calculations.
Valid measured data for gaseous pollutant emissions calculations shall start after the engine coolant temperature has reached 343 K (70 °C) for the first time or after the engine coolant temperature is stabilised within +/– 2 K over a period of 5 minutes, whichever comes first; in any case it shall start no later than 20 minutes after starting the engine.
Zero verification of the gas analysers shall be conducted at least every 2 hours during an in-service monitoring test.
The results obtained with the checks performed in accordance with point 7.1 may be used to perform a zero drift correction.
The drift verification shall be performed only if no zero drift correction was made during the in-service monitoring test in accordance with point 7.2.