The unit uses software developed by Edit Associates and replaces the analogue Hartridge unit that has been the inspection standard.
Effectively, the system narrows tolerances for all correlation testing of smoke test equipment. Its adoption by the VI means all test equipment makers seeking certification for their machines will have to pass a correlation test to the RTM 430 standard. Bosch says the Inspectorate has been trialling the unit for more than a year and has informed all vehicle test stations of the change.
“With diesel engines becoming more efficient and cleaner, some vehicles are now consistently producing very low opacity readings on smoke meters,” says Paul Lees, Bosch product manager for workshop equipment.
“It is to the benefit of the whole MoT fraternity that equipment will now be accurately calibrated to today's digital standards.”
As well as equipment meeting correlation tests, operating software has to include a 'fast pass' function, whereby the meter will automatically stop the test sequence if the measured value of the first acceleration is less than or equal to the 'fast pass' smoke limit.
The result is then passed to the printer and equipment interface. If the value is not achieved the machine will continue with the normal test sequence of up to six accelerations.