Haltech E6GMX - Manual (Page 107)

E6GMX Manual
107
on the operation of the ECU. It is only the position of the triggering edge that is of
importance. Example 2(b) shows the same trigger angle but with the opposite trigger edge.
Some trigger devices have uneven pulse widths to indicate the position of a specific cylinder
(often cylinder 1). If rising edges were used as the trigger edge then there would be a
variation of 20° between the trigger for cylinder 1 and all other cylinders. This would lead to
cylinder 1 being 20° more advanced than all the other cylinders. To ensure even ignition
timing the trigger edge would be the falling edge and the trigger angle would be 60° BTDC.
As describe above, Hall effect triggers produce a signal that is made up of transitions or edges
and these edges correspond to a specific angle and as a result the ECU need to be configured
to trigger on a specific edge.