Well curiosity got the best of me so I pulled a coil pack (Magnetti Marelli) from the Monster parts cave and took some measurements.
I used an LCR which is just a more specialised meter for reading inductance/capacitance/resistance.
I got 0.5 ohm on the primary (input side).
7.43k ohm on the secondary.
The secondary is not centre tapped, it is a single coil. I got no readings between the two coils.
However, these measurements are taken at tiny voltages provided by the meter. The secondary of the coil puts out somewhere in the range of 30,000 volts+. These high voltages like to travel (hence they jump the gap on the sparkplug). This is why insulation tests are always carried out at high voltages. So if there was any damage to the windings insulation and some conductive dampness for good measure, the voltage would easily jump across the damaged sections. This would not show on a multimeter and would require a very high voltage flash test or running the coil and measuring leakage.
Disassembly may provide the answer if the insulation appears to be damp or damaged, so get that hammer out Woj.
While working this out I realised how easy it would be to make a taser gun with a 12v square wave and one of these coils. However real tasers carry a little bit more current and start at about 50,000 volts.
Regardless it would still make an excellent tool for prodding cattle and traffic wardens.
I used an LCR which is just a more specialised meter for reading inductance/capacitance/resistance.
I got 0.5 ohm on the primary (input side).
7.43k ohm on the secondary.
The secondary is not centre tapped, it is a single coil. I got no readings between the two coils.
However, these measurements are taken at tiny voltages provided by the meter. The secondary of the coil puts out somewhere in the range of 30,000 volts+. These high voltages like to travel (hence they jump the gap on the sparkplug). This is why insulation tests are always carried out at high voltages. So if there was any damage to the windings insulation and some conductive dampness for good measure, the voltage would easily jump across the damaged sections. This would not show on a multimeter and would require a very high voltage flash test or running the coil and measuring leakage.
Disassembly may provide the answer if the insulation appears to be damp or damaged, so get that hammer out Woj.
While working this out I realised how easy it would be to make a taser gun with a 12v square wave and one of these coils. However real tasers carry a little bit more current and start at about 50,000 volts.
Regardless it would still make an excellent tool for prodding cattle and traffic wardens.
