ATI Technologies SmartTachSmartTach, User Manual

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PARAMETERS
Page 4-4 SmartTach Operating Manual
02 - Patterns/Pulses per Cam/Dyno Revolution
Parameter Group:
Setup!
Range: 1-9999 pulses
Increment: 1 pulse
Default: 1 pulse
Purpose: This parameter is used calculate Engine RPM or Chassis
Dynamometer speed. This parameter is required and if not set
correctly will result in improper measurements.
How to Set: Before setting this parameter you must know if the signal is a pattern
of pulses or a single pulse that repeats. Patterns refer to
asymmetrical pulse groups where the period between pulses varies
over one camshaft revolution, as in a trigger wheel with a missing
tooth or an odd fire engine. For these asymmetrical “Patterns” you
would enter the number of times the pattern repeats itself per Cam
revolution, you will also need to enter the number of pulses per
pattern(Parameter 03) . For equally spaced pulses you would enter
the number of pulses per camshaft or Dyno revolution.
Examples:
1 Cam Revolution
or
1 Dynometer Roll Revolution
A
B
C
Figure 4 - 1: Parameter 2 Pulse Examples
A
is a “Pulse” type signal from a sensor like a 12 Pulse/Rev Dyno Roll
or a 6 Pulse/Rev Crankshaft sensor. For this example
Parameter 02=12
B
is a “Pattern” type signal from a sensor like a 6-1 tooth crankshaft
sensor. For this example Parameter 02=2
C
is a “Pulse” type signal from a single plug wire on a distributor. For
this example Parameter 02=1