Haltech IG5 - Manual (Page 81)

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INPUT PLUG OUTPUT PLUG
Pin Colour Wire Function Pin Colour Wire Function
A BLUE Primary Trigger (-) A BLACK Ground
B WHITE Primary Trigger (+) B RED +12 Volts
C GREEN Secondary Trigger (+) C YELLOW Primary Trig
D GREY Secondary Trigger (-) D BROWN Secondary Trig
Figure E.4
The magnetic pick up is basically a piece of wire wrapped around a magnetic core and
attached to the sensor face, which is called the pole piece. The physical size and shape of
such a pick up can take many forms. This type of pick up has either two wires (one positive (
+ ), and the other negative ( - )), or three wires with the third being a shield. The wires are
sometimes marked as such, but more often than not they are unmarked.
It is very important that the positive pin go to the input pin of the reluctor adaptor (pin
B for Primary trigger, pin C for Secondary trigger), and that the negative go to the
ground reference pin (pin A for Primary trigger, pin D for Secondary trigger).
If you cannot tell which wire is the positive from markings or wire colour, then it would be
necessary to check the signal going into the reluctor adaptor using an oscilloscope.
When ferrous metal ie. metal that a magnet will attract, is passed very close to the pole piece,
the pick up will generate a voltage similar to figure E.3.5 on the positive wire. The amplitude
of the signal will vary with the speed at which the ferrous metal passes the pole piece. At low
speeds the signal may only be several hundred millivolts, but at high speeds it could rise to 20
volts or more. The sudden drop in the signal from positive to negative seen in figure E3.5
corresponds to the metal being directly in line with the sensor. As can be seen, the signal is
not the square wave signal that is required by the IG5. Also at low speeds the signal voltage
is too low. This is why the Reluctor adaptor is used.
The voltage input of the reluctor adaptor must first go to a positive peak, which arms the
circuit in the Reluctor adaptor. When the signal rises to approximately 70 - 80% of the peak
value the Reluctor adaptor will generate a falling edge, and when the signal crosses zero volts
the Reluctor adaptor will generate a rising edge that is used to trigger the Haltech ECU. If the
wires are reversed and the signal goes negative first, the Reluctor adaptor will generate a pulse
but it will NOT trigger the IG5 correctly and mistimed ignition events may occur. For
instance, the timing may retard as revs increase or multiple triggers can be generated.
Incorrect wiring of a reluctor trigger can cause major problems. If you are using a reluctor
pick up ensure that they are wired with the correct polarity.
Note: in the ignition setup page trigger edge should be set to rising.
A variation on this type of pick up uses a magnet moving past the pole piece, instead of
ferrous metal, but generating the same wave form. An example of this type is the MSD flying
magnet crank trigger. This pick up can be used with the reluctor adaptor to trigger the IG5
ECU.