NPL's Vehicle Emissions Simulator assesses the performance of Vehicle Emission analysers. Such instruments are used to establish whether exhaust emissions from motor vehicles exceed statutory limits. The system supplies test gases from NPL's standard gas cylinders to an MOT analyser at ambient temperature. These gases provide a repeatable reference concentration that can be used for regular calibration of these instruments.

NPL's MOT Test Gas Simulator satisfies 'ISO 3930 OIML, third edition 2000-09-01' of the Organisation International de Metrologie Legale (OIML) applying to the testing of MOT analysers.

Application

The system allows eight different test gases and a zero test gas mixture to be delivered to the instrument under test. The system also has a water vapour generator, which can deliver the zero gas (nitrogen) at 90% relative humidity. All gases are delivered at ambient temperature and the system will not dilute or alter the concentration of the test gas mixtures. The concentration of the test gases can easily be tailored to suit specific application requirements. The test gases are traceable to UK primary gas standards ensuring accuracy, consistency and international comparability of measurement results.

The system carries out automatic diagnostic tests to evaluate:

• Measurement repeatability
• Instrument stability and drift
• Instrument response
• System calibration
• Sample leakage
• Residue/memory effects
• Low sample flow

All diagnostic tests are carried out automatically under PC control.

If you would like further information please contact us.