ATI Technologies SmartTachSmartTach, User Manual

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PARAMETERS
Page 4-12 SmartTach Operating Manual
10 - Spark Input Threshold Level
Parameter Group:
SpkInp
Range: 0.00-5.08 volts
Increment: 0.04 volts
Default: 2.00 volts
Purpose: This parameter is used to adjust the input sensitivity of the Spark input
signal conditioning circuit to accommodate weak signals without
compromising noise immunity on strong signals.
How to Set: For normal operation, this parameter should be set as high as
possible without causing the SmartTach to miss spark pulses. This is
normally about 20% below the value at which erratic flashing of the
front panel PULSE LED is noticed.
For the absolute maximum measurement accuracy this parameter
should be set as low as possible, keeping in mind that if the setting is
too low (too sensitive), the SmartTach may trigger on spurious noise.
The Spark Input Phase Correction parameter should also be used to
"tune-out" the phase error.
A typical setting of 2.00 volts will work well with most Inductive
Pickup type sensors. Please note that the direction in which the
pickup is clamped to the spark plug wire is important (effects its
output level). The direction of the pickup should be reversed if
good results are not obtained.
When connecting directly to the ignition coil negative terminal, a
typical setting of 4.00 volts will work well for most applications.