Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:9:p43
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 9 (pt 43/71)
Character Range: 333092–336198

PT measurement).

              NO

              CLD or HCLD analyser for the determination of the oxides of nitrogen. If a HCLD is used it shall be kept at a temperature of 328 K to 473 K (55 °C to 200 °C).
              C Converter

              A converter shall be used for the catalytic reduction of NO2 to NO prior to analysis in the CLD or HCLD.

              B Cooling bath (optional)

              To cool and condense water from the exhaust sample. The bath shall be maintained  at  a  temperature of 273 K to 277 K (0 °C to 4 °C) by ice or refrigeration. It is optional if the analyser is free from water vapour interference as determined in Annex III, Appendix 5, Sections 1.9.1 and 1.9.2. If water is removed by condensation, the sample gas temperature or dew point shall be monitored either within the water trap or downstream. The sample gas temperature or dew point must not exceed 280 K (7 °C). Chemical dryers are not allowed for removing water from the sample.

              T1, T2, T3 Temperature sensor

              To monitor the temperature of the gas stream.

              T4 Temperature sensor

              To monitor the temperature of the NO2-NO converter.

              T5 Temperature sensor

              To monitor the temperature of the cooling bath.

              G1, G2, G3 Pressure gauge

              To measure the pressure in the sampling lines.

              R1, R2 Pressure regulator

              To control the pressure of the air and the fuel, respectively, for the HFID.

              R3, R4, R5 Pressure regulator

              To control the pressure in the sampling lines and the flow to the analysers.

              FL1, FL2, FL3 Flowmeter

              To monitor the sample by-pass flow rate.

              FL4 to FL6 Flowmeter (optional)

              To monitor the flow rate through the analysers.

              V1 to V5 Selector valve

              Suitable valving for selecting sample, span gas or zero gas flow to the analysers.

              V6, V7 Solenoid valve

              To by-pass the NO2-NO converter.

              V8 Needle valve

              To balance the flow through the NO2-NO converter C and the by-pass.

              V9, V10 Needle valve

              To regulate the flows to the analysers.

              V11, V12 Toggle valve (optional)

              To drain the condensate from the bath B.

1.3.                            NMHC analysis (NG fuelled gas engines only)

1.3.1.                        Gas chromatographic method (GC, Figure 9)

              When using the GC method, a small measured volume of a sample is injected onto an analytical column through which it is swept by an inert carrier gas. The column separates various components according to their boiling points so that they elute from the column at different times. They then pass through a detector which gives an electrical signal that depends on their concentration. Since it is not a continuous analysis technique, it can only be used in conjunction with the bag sampling method as described in Annex III, Appendix 4,