Ok, i can sort of follow that, your explanation is pretty good for me to follow. Its good to know that the capacitor is in a low voltage part of the circuit and wont get damaged but i didnt read what you said the capacitor does and how do you come up with the magical output figure of 12 volts???? I can tell for sure that no AC regulator would shunt at 12 volts, especially this particular brand. Most will be set to at least 13.8 volts and some of the higher performance racing ones could be as high as 14.7 or 15 volts for nice bright lights as we found in the last circuit that had a 15 volt zener. My research from what ive heard people say is that this particular one is regulating somewhere around 14-14.7 volts. How do we find out exactly what is working at? What is the component that is making the descision on the shunting voltage? on the last ones we looked at they were easy as they had 13 and 15 volt zeners, but on this circuit we have a 8.2V zener and its not doing the same job as the zeners in the last circuits.
Can we safely say this is not a AC regulator ment for 6 volt systems yet?
I agree, we need the experts to drop in again
The capacitor may be used as a reservoir to help stabilise the dc voltage, but I am guessing here. I just used 12V as a ballpark figure, quite a bit of maths may need to be done to determine exactly what voltage that regulator would handle other than pysically testing it and measuring the output.
In our case the only way is to get it wired into a a bike and measure the voltage or use a 24V transformer.
The zener is definitely the main component that determines the regulating output and as far as I know it does not have to be 12v or 15v to regulate at 12 or 15, one could also have a 8.2v zener and together with a voltage devider made up of series resistors it can still regulate at higher voltages than the zener voltage. It mostly depends on the circuit design and the particular approach of the person who designed it. for example if you put a diode in series with an 8.2 V zener the voltage changes to 8.9V. Unfortunately I am not so well informed on all these tricks and application methods, so we can only hope someone who knows more about this comes along.
It would be hard to determine whether it is for 12v or 15V unless we understand the design. In actual fact most likely the 6V AC regulator is exactly the same with just one component value change, which does not necessarily mean the Zener.