Innovate Motorsports LMA-3 User Manual
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the injector. Because the pulse is therefore active when the voltage on the pin is at ground,
negative duty cycle is measured.
So called peak-hold injectors (as opposed to saturated injectors), work differently. Their drive
signal first goes to ground for a high current opening pulse, then rises to 8-10 Volts for the hold
period. Because the LMA-3 sees everything above 2.5V as “high”, it will be able to see only the
peak period. On some peak-hold systems it is possible to connect the CHx+ input of the LMA-3 to
12V at the injector and connect the CHx- input to the injector signal to still measure correctly. But
that is not always the case. The LogWorks 2.0 Manual shows an alternative method. If the above
method works, it actually measures positive duty cycle.