TCi EZ-TCU, Руководство пользователя

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RPM Module
There are two basic options for supplying the EZ-TCU™ with an RPM input.
1. Clean, processed Tach signal from engine electronics
Electronics involved in running the engine – fuel injection, ignition, etc. – will need to know
engine RPM. So there may be an existing tach signal wire that can be tapped into. The EZ-
TCU™ requires a square wave type tach signal that pulses once per cylinder firing. Ignition
systems – such as aftermarket capacitive discharge (CD) ignition boxes – often have dedicated
“Tach” outputs that are a perfect RPM signal source for the TCU.
If using a clean, processed Tach signal, the TACH IN / RPM MODULE wire in the EZ-TCU™
wiring harness is connected directly to that source - the “Tach” output from an ignition box,
etc. The RPM Module included with the kit is not used in this case. And no part of the EZ-
TCU™ system is connected to the coil.
2. Inductive coil
Another RPM signal source is the negative side of the ignition coil in a traditional dwell
controlled inductive ignition system. One in which the coil is fed power on one side and is
charged by grounding the other side - either by “points” or some form of electronic module.
An HEI is one example of this type of ignition system.
To use this RPM signal option, the
RPM Module is required . The RPM Module connects to
the negative side of the coil and outputs a “Tach” signal to the TCU. The RPM Module is
connected as follows:
Wire color Connection
Black Engine block
Black Engine block
White Negative side of coil
Yellow TACH IN / RPM MODULE wire in EZ-TCU™ wiring harness
The RPM Module is provided to allow this convenient installation option. But keep in mind
that it has limitations. The negative side of an ignition coil is one of the noisiest points on the
engine. In most applications, the RPM Module will be able to deal with this and feed a clean
RPM signal to the TCU. But the old saying – garbage in, garbage out - applies here. If the