alternator excitation

[True Blue]

Can anyone explain what alternator excitation is needed for. What does it do?
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[Bezzer]

Very roughly it's the control of the alternators output. Current is increased/excited to the rotor which increases it's magnetism and the effect increases the voltage from the stator. It's just the control of AC voltage from the alternator and to what degree you "excite" the magnets varies the output.
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I used to be indecisive but now I'm not quite so sure.

[True Blue]

Sounds technical. Do you know of any websites where I could read about it in detail. I was wiring up an engine today and it worked fine. However, I'd like to understand how it works in more detail.
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Past >>>> Honda NSR 125 >>>> Suzuki GSXR 600 K1 >>>> Suzuki GSXR 600 K4 >>>>Kawasaki Z1000 DAF >>>>Suzuki RMZ 250 >>>> Current >>>> KTM Superduke R 1290 >>>>

[Bezzer]

Don't know offhand but sure if you google the key words you'll find something to help.
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I used to be indecisive but now I'm not quite so sure.

[stinkwheel]

You know how an alternator works yeah? Spin a magnet round an electrical coil (or vice versa) and it generates electricity.

Well on some bikes that magnet is not a permanant magnet but an electromagnet. Obviously that won't work until there is electricity going through it. This electricity is your "excitation" current. Increasing and decreasing this current alters how magnetic the electromagnet is and thus alters the alternator output.

On this type of 'field coil' alternator, the voltage regulator varies the power supply (or excitation) to the field coils in response to fluctuations in the alternator output.

Obviously, this sort of bike will not start with a flat battery.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[True Blue]

Cheers stinkwheel, I understand it now. I should have mentioned, it wasn't a bike engine I was wiring. It was one of these...

https://www.dieselgenerators.com/images/260-Dorman-2.jpg
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Past >>>> Honda NSR 125 >>>> Suzuki GSXR 600 K1 >>>> Suzuki GSXR 600 K4 >>>>Kawasaki Z1000 DAF >>>>Suzuki RMZ 250 >>>> Current >>>> KTM Superduke R 1290 >>>>