ISO 20574:2019 pdf free
ISO 20574:2019 pdf free.Road vehicles一Durability test method for starter motor for stop and start system
The durability test is performed with an engine simulator or an engine. The following test types can be selected. See Table 1 for comparison of each test type.
1) Engine, using bench controller to control fuel/spark to specifically achieve pre-determined cranking time and overrunning time (see Table 3).
2) Engine, using its engine ECU to control the test parameters.
3) Engine simulator, using engine waveform data provided by engine and/or vehicle manufacturers as input to simulator (for cranking time, overrunning time, or torque) (see Table 3).
4) Engine simulator, using synthetic pattern or engine simulation model where starter motor manufacturer or engine and/or vehicle manufacturers define values for torque, cranking and overrunning behaviour (see Table 3).
The following items should be specifically considered:
1) In case of engine simulator, multiple starter motors can be tested simultaneously with the same ring gear. In that case, the orientation of the starter motors deviate from those of the target application.Hence, the usage of multiple starter motors shall correspond to the test purpose (e.g. verification of brush durability but not verification of pinion and ring gear durability).
2) The starter motor manufacturer and engine and/or vehicle manufacturers should agree starter motor temperature level during the durability test. Different approaches to define temperature level are established.
For example:
一test at maximum brush temperature defined by starter motor manufacturer;
一test at maximum brush temperature derived from vehicle real drive cycle; and
一test at an average brush temperature derived from brush temperature distributions of vehicle real drive cycle.
Each approach covers different testing purposes such as focusing on thermal stress, test duration,mechanical loads or balanced field representation.
3) The starter motor manufacturer and engine and/or vehicle manufacturers should define the test pass criteria and define test stop criteria according to Table 6.
In the event that the engine ECU (or engine data) is not used in the setup (test types 1, 3 and 4, see Table 1), it shall be necessary to decide and setup specific values for cranking time, or overrunning time (see Table 3).
In that case, Table 2 should be used to help starter motor manufacturer and engine and/or vehicle manufacturers to reach agreement on the necessary parameters as a part of the planning phase.ISO 20574 pdf free download.
