Haltech E6S - Manual (Page 127)

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E.4 Ignition Output
The E6S ECU has one dedicated ignition output, but the two Auxiliary Outputs can also be
used for ignition outputs to allow for some Direct Fire applications (See Appendix B). Twin
spark engines that fire two spark plugs within one cylinder simultaneously (with two coils,
twin distributors and two spark plugs per cylinder) need only one output channel but two
igniters (one for each coil) both connected to the same ignition output.
The ignition signals on the E6S are generated by the same type of drivers as the injectors ie.
the output pulls to ground when it is switched on. These output signals cannot be used in
any circumstances to drive an ignition coil directly: they must drive some form of
igniter. An igniter is a device which is capable of sinking the large currents required to charge
the coil. The E6S kit is normally supplied with a Haltech igniter module. This “intelligent”
igniter module performs current limiting and dwell control on its own, and is the preferred
ignition module to be used with the E6S system. The back of the igniter can become
extremely hot. Refer to Chapter 1 for details on mounting.
The Regitar equivalent part, 1G-H004, has been tested and found NOT to work satisfactorily
with the E6S ECU. Please do not use it.
Tailoring the Ignition Output Signal
The E6S has the flexibility to tailor the ignition output signals to suit different ignition
systems. The parameters that may be adjusted can be found in the Ignition Setup, area (see
sec.4.6.1). The default setting for the ignition output, selected to suit the supplied Bosch
igniter, is a 70/30 constant duty cycle signal firing on the falling edge.
Constant Duty Cycle vs Constant Charge
The E6S is best suited to intelligent igniter modules that perform their own dwell control.
NOTE: IF USING THE HALTECH IGNITION MODULE SET THE OUTPUT TYPE
TO CONSTANT DUTY.
The duty cycle of a square wave is the ratio of its high time to its period. E.g. a 70/30 duty
cycle signal is high for 70% of its period and low for the remaining 30% regardless of
frequency, as shown in figure E7. Constant duty can also be used on aftermarket capacitive-,
inductive- or multiple-spark discharge systems such as MSD or Jacobs.