Date: Thu, 20 Jan 2005 20:21:21 GMT
From: hohnospamlid.invalid (Goran Larsson)
Subject: Re: Opened DI Casette - For those interested

In article <>, Everett M. Greene <> wrote: > Nobody has identified any "electronics" > in the units and even if there is, that might not be the > cause of the failures. What makes you believe that there is no electronics inside a DI cassette? AFAIK the DI cassette contains two major functions, a capacitive discharge ignition system and an ion sensing circuit. Capacitive discharge ignition system One 12V to 400V voltage converter. One large capacitor charged to 400V. Four (one for each spark plug) capacitive discharge spark generators with - A thyristor (red DI) or a triac (black DI) - drive electronic for thyristor/triac for each spark plug - HT coil for each spark plug The DI connector has one pin for each spark generator. The ignition timing is done by the Trionic ECU. Ion sensing circuit One 12V to 80V voltage converter. Four (one for each spark plug) ion sensing circuits using the 80V to ionize the gasses in the spark plug gap. The DI connector has two pins for the ion signal, one for cylinder 1 and 4, one for cylinder 2 and 3. The Trionic ECU knows which cylinder is in the combustion phase. The circuit board containing the electronics is the same size as the expoxy filled area, i.e. the whole length of the cassette. -- G–ran Larsson

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