Ignition Control

Distributor:

The electronic ignition system is known as a Constant Energy System. In this system the distributor, incorporates a standard automatic advance system, cover, rotor arm, anti-flash shield, reluctor, and a pick-up assembly. The reluctor is a gear-like component and is mounted on the distributor shaft. The pick-up consists of a winding around a pole piece attached to a permanent magnet. The pick-up is prewired with two leads forming a two pin block connector.

Fig. 3 Ignition Amplifier:

When the reluctor tooth passes across the pick-up the magnetic field strength is intensified creating a voltage in the winding. The rise and fall of this voltage signal created by the reluctor and pick-up assembly is sensed by the amplifier, causing the amplifier to switch the current flowing in the primary winding of the ignition coil on and off.

Two ignition coils are incorporated on the V12 engine. The main coil primary winding and the auxiliary coil primary winding are connected in parallel. The high voltage section of the auxiliary coil is not used and the outlet is sealed. The auxiliary coil enables the ignition system to achieve the required performance at high engine speeds under load. The constant energy electronic ignition system employs output current limiting and variable dwell for optimum performance. A long dwell is provided at high speeds for adequate energy storage in the coil and a short dwell is provided at low speeds for minimum power dissipation. The output current limiting function of the amplifier maintains the storage energy for spark, and the system open circuit voltage constant over a wide engine speed range. It eliminates the need for a ballast resistor while ensuring correct current flow at all times even during engine cranking. No current flows through the coil when the ignition is switched on and the engine is stationary.

The amplifier assembly consists of a solid state electronic amplifier module, a Zener diode to protect the amplifier in the event of a current surge, a moulding containing two resistors and a suppression capacitor. The resistors provide two engine speed signals one for the tachometer and one for the ECU.

WARNING: The amplifier is a sealed unit containing BERYLIA. This substance is extremely dangerous if handled. Do not attempt to open the amplifier module.