Haltech IG5 - Manual (Page 70)

66
Figure E8. Illustrates Charge Time & Break Time
Constant charge time ignition using a dumb igniter is moderately inferior to that using an
intelligent igniter with dwell control as it does not compensate for power variations or thermal
effects.
Note: For safety and reliability, always use igniters that are internally current
limited.
The Output Signal
The BOSCH type Ignition Module operates on the falling edge of the output signal. This
means that the spark is fired when output signal drops to 0 V. Many, but not all OEM
ignitions operate with the same trigger logic. Most after-market ignition systems fire their
spark on the falling trigger edge (same as points). Make sure that you set the ignition output
trigger edge correctly. If set to the wrong edge, the timing will be out by a significant amount
and engine damage may result.
B.5 Alternative Ignition Systems
The output of the BOSCH type Ignition Module can be used to trigger after-market ignition
systems such as MSD or Jacobs. It is possible to invert the ignition output of the IG5 through