Linearity requirements Sample Clauses

Linearity requirements. The PN analyser including the sampling line shall fulfil the linearity requirements of paragraph 3.2. of Annex 5 using monodisperse or polydisperse soot-like particles. The particle size (mobility diameter or count median diameter) shall be larger than 45 nm. The reference instrument shall be an Electrometer or a Condensation Particle Counter (CPC) with d50 = 10 nm or lower, verified for linearity. Alternatively, a particle number system compliant with UN Regulation No. 154 on WLTP. In addition, the differences of the PN analyser from the reference instrument at all points checked (except the zero point) shall be within 15 per cent of their mean value. At least 5 points equally distributed (plus the zero) shall be checked. The maximum checked concentration shall be > 90 per cent of the PN analyser nominal measurement range. If the PN analyser is calibrated in parts, then the linearity can be checked only for the PN detector, but the efficiencies of the rest parts and the sampling line shall be considered in the slope calculation.

Linearity requirements. All analysers, flow-measuring instruments, sensors and signals shall comply with the linearity requirements given in Table A5/1. If air flow, fuel flow, the air-to-fuel ratio or the exhaust mass flow rate is obtained from the ECU, the calculated exhaust mass flow rate shall meet the linearity requirements specified in Table A5/1. Table A5/1 Measurement parameter/instrument |𝑥𝑚𝑖𝑛 × (𝑎1 − 1) + 𝑎0| Slope a1 Standard error of the estimate SEE Coefficient of determination r2 Fuel flow rate1 ≤ 1 % xmax 0.98 – 1.02 ≤ 2 % of xmax ≥ 0.990 Air flow rate2 ≤ 1 % xmax 0.98 – 1.02 ≤ 2 % of xmax ≥ 0.990 Exhaust mass flow rate ≤ 2 % xmax 0.97 – 1.03 ≤ 3 % of xmax ≥ 0.990 Gas analysers ≤ 0.5 % max 0.99 – 1.01 ≤ 1 % of xmax ≥ 0.998 Torque3 ≤ 1 % xmax 0.98 – 1.02 ≤ 2 % of xmax ≥ 0.990 PN analysers4 ≤ 5 % xmax 0.85 – 1.155 ≤ 10 % of xmax ≥ 0.950 1 optional to determine exhaust mass flow.

Linearity requirements. Table 7 Linearity requirements of instruments and measurement systems Measurement system μmin / (a1 - 1)+ a0/ Slope a1 Standard error SEE Coefficient of Determination r² Engine speed ≤ 0.05 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Engine torque ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Fuel flow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Airflow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Exhaust gas flow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Diluent flow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Diluted exhaust gas flow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Sample flow ≤ 1 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Gas analyzers ≤ 0.5 % max 0.99 - 1.01 ≤ 1 % max ≥ 0.998 Gas dividers ≤ 0.5 % max 0.98 - 1.02 ≤ 2 % max ≥ 0.990 Temperatures ≤ 1 % max 0.99 - 1.01 ≤ 1 % max ≥ 0.998 Pressures ≤ 1 % max 0.99 - 1.01 ≤ 1 % max ≥ 0.998 PM balance ≤ 1 % max 0.99 - 1.01 ≤ 1 % max ≥ 0.998 Humidity measurement device ≤ 2 % max. 0.98 – 1.02 ≤ 2 % ≥ 0.95 "