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BA314001-en
After 20 seconds at full throttle the green LED once
again flashes slowly, indicating a return to normal idle
speed. The operator should rapidly return the throttle
to the idle position.
After 20 seconds at idle, measurements are
terminated. At this point the LED is turned off and the
screen flashes a brief “TEST COMPLETED“ message.
The screen then displays the overall test result in bold
characters, together with some other test data which
may aid maintenance personnel to identify any
emission-related faults in the engine or fuel
management system.
To retain the simplicity of the test procedure, manually record the test result, the date/time and
the vehicle or plant identification information.
If it is desired to store the test data directly on a computer connected to the RS232 port on the
MPM-4M, use the supplied “MPM-View” to generate a real-time graph of the PM concentration
profile over the complete test, and record the second-by-second test data in an EXCEL
compatible file. (See the supplied MPM-View operator manual). NOTE: Include the test vehicle
identifier and the date (in YYMMDD format) in the file name when prompted, to facilitate search
and retrieval of stored files.
4.5
Free Acceleration Test
The format of the free acceleration test is similar to that of the Stall Test, but there are some
important differences, notably:
testing is performed with the transmission in neutral.
there are three acceleration peaks, compared with just one in the Stall Test.
For completeness, the full test procedure follows.
Insert Probe
Insert the supplied sample probe fully into the exhaust
of the vehicle or plant under test, using the spring wire
retainers to secure the probe in position. Confirm that
the engine is running and at normal operating
temperature, with the transmission disengaged in
accordance with the MDG 29 procedures.
