waveforms > ignition > amplifier earth > Ignition Amplifier Earth

goodThis is a good waveform

Ignition Amplifier Earth Waveform Notes

The earthing on the ignition amplifier (also referred to as the module or the igniter) is vital to the operation of the ignition system and is often overlooked as an area for potential problems.

The earth connection, if not in good condition, can cause a reduction in the primary current that will effect the current limiting (or dwell control) circuit. It is therefore vital that this important connection is tested and rectified if it is found to be outside of its operational limits. An earth return circuit can only be tested while the circuit is under load and this therefore makes continuity testing to earth with a multimeter inaccurate. As the coils primary circuit is only complete during the dwell period, this is the time that the voltage drop should be monitored.

Ensure that the ‘voltage ramp’ does not exceed 0.5 volts. The ‘flatter’ the resultant waveform the better. A waveform with virtually no rise, shows that the amplifier/module has a perfect earth. If the ‘ramp’ is too high, another earth wire can be soldered in parallel with the original earth connection will be beneficial.