EDI TSG-416, Руководство по обслуживанию

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TSG ‐ 416 IGNITION SYSTEM
03 ‐ 3
Operation
With this system, the GCP monitors the engine
speed and operating temperature and decides
what degree of spark advance is correct for all of
the operating conditions. Because timing is set
for life inherently in the design of the engine, and
there are no moving parts in the ignition system
itself, no maintenance is required except for
periodic spark plug checks. The system provides
for fixed spark advance at start-up, for cold
weather starting, and for “average value” default
attention has been given to spark optimization
for excellent fuel economy in the warm-up mode.
The spark plugs are paired so that one plug fires
during the compression stroke and its
companion plug fires during the exhaust stroke.
The next time that coil is fired, the plug that was
on exhaust will be on compression, and the one
that was on compression will be on exhaust. The
spark in the exhaust cylinder is wasted (referred
to as the “waste spark”) but little of the coil
energy is lost.
Engine Speed and Crankshaft Position
The crankshaft position and speed information
comes to the GCP from the Crankshaft Position
(CKP) Sensor, mounted near the crankshaft
pulley. The CKP Sensor is triggered by teeth on
a trigger wheel located on the crankshaft pulley.
The pulse frequency indicates crankshaft speed
and a missing tooth indicates crankshaft
position.
Engine Temperature
The Engine Coolant Temperature (ECT) Sensor
sends engine temperature information to the
GCP. It is located in the rear coolant outlet pipe.
Fuel Octane Level Adjustment
In the event that the engine is operated on dry
fuels such as natural gas, compressed natural
gas (CNG), or liquefied petroleum gas (LGP),
timing can be modified by GCP “Fuel Type”.
Ignition Coil Driver
The GCP switches 2 individual ignition coils on
and off at the correct times to give the desired
spark advance. Ignition timing is adjusted
constantly by the GCP. Many factors including
all the sensor inputs, affect the final ignition
setting.
Run Mode
The GCP interprets engine speed above 200
rpm as Run Mode. The Base Spark advance
(BSA) is calculated by the GCP processing the
engine speed input.
Transient Mode
This function is to provide detonation protection
when the engine load is increased rapidly by fast
opening of the throttle plate.