15 amp stator

[alexanderfoti]

Hi all

I am about to buy the 15 amp stator for my engine, but I just had a thought.

How do I know I haven't already got a 15 amp stator?

Ideally I would like to find out without removing the flywheel, any ideas?s

[Nanko]

Test if you are able to blow the filaments of an old H4 bulb with Both filaments
connected parallel.
Without regulator and rectifier at 3600 RPM the voltage should be high enough
to melt them in seconds

[alexanderfoti]

Awesome! cheers

Hold on, I only have 2 wires coming from the stator, I assume this means I have a 4 amp stator?

[coachgeo]

Test if you are able to blow the filaments of an old H4 bulb with Both filaments
connected parallel.
Without regulator and rectifier at 3600 RPM the voltage should be high enough
to melt them in seconds

Well if engine can be started the logically it could be tested with an typical everyday Amp/volt meter. My assumption is he's asking this with thought of NOT cranking engine over; as in physical identifying marks such as counting the number of coil blocks on the ring or size or, number of wires etc etc.

[alexanderfoti]

That would be a preferred way, but once the build is finished, I will have easy access to the flywheel side of the engine if it isnt. Essentially, I will draw a 4 amp load, and see if the battery still charges on an ammeter (or try the bulb method). IT would be easier to know the capacity so that I can design the electrical system, as I am rewiring from scratch.

[Nanko]

If you want to measure the 15 A alternator output current , a 5$ multimeter is not good enough
Also you need a load which matches maximum power generator.
A bulb is all in one(more or less) and good enough to check if the stator is 4 or 15 Amp.

[alexanderfoti]

I have a fluke meter, but will go down the bulb method, thanks.

[XLerate]

Fluke: end of conversation ha!

Using your dandy little Fluke with Ohm's Law applied you should have your answer. Measure the 'R' Resistance in your stator & calculate against the 'E' Voltage, assumably 12V? You'll then have the maximium 'I' Amperage output available, I think....?

http://www.the12volt.com/ohm/ohmslawcalculators.asp

[alexanderfoti]

Heh, this bit I got confused with, as the stator outputs different voltages dependend on RPM, so I should be calculating using 12 (or 13.2 etc)

[Nanko]

Stator output depends on many things , diameter rotor , rotor magnetic properties , airgap , number of turns , number of yokes etc.
All these parameters cannot be measured with a multi meter , even if its a FLUKE

[alexanderfoti]

Yeah, I mean the only real variable if I haven't fiddled with anything