<< Nrath,

If cannondale says the voltage should be at 13.5 to 14.5 you have just found a kink in thier armor. What this tells me is the stator is under rated and by upping the voltage you reduce the current, amprage if you will. The stator is rated by the amprage. >>



Current isnt being reduced or his batteries would not burn up at 16 volts. When the load is the same for both the 14 volts and 16 volts, you will have more current at 16, when he runs with the lights on he uses the extra current that would burn his battery. He is measuring at the battery on the output of the regulator not the stator

A stator is rated in watts. The regulator is defective.

 

watts of power you are speaking of, is the abillity of current. Current is the usage of electricity.

Simple equation here:

100 watts devided by 14 volts = 7.14amps

100 watts devided by 16 volts = 6.25amps

The higher the voltage the lower the amperage. Watts is power, amperage/current is the usage of power.

On a DC circut you can load a generator or rectifier to 150% of it's rated value momentarally, as long as cooling is allowed and the load isn't constant.

What I'm saying is your overloading the stator inturn it's frying your batteries.

By running the lights he maxximizes the stator untill it can not put out any more, hense voltage draw down. In this case the battery is the buffer, shock obsorber if you will, or filter how ever you want to look at it. So the load is so graet on the current stator on the machine that the battery is over charged and undercharged by the radical voltage change dictated by the rpm's

It's like a elastic band, if you stretch it and retract it to it's maxximum amount the band will braek quickly. If you just stretch it to 50% of it's limits it will last for years.

Very tough to describe excitation, sensing and triggers of a stator/rectifier. I just keep getting key board tyde, sorta like tounge tyed.

 

Ok, was just sitting here thinking about this. Before you know there is a problem you must deal with the facts.

Take the positive lead to the stator off. Install the two leads of a multi meter in series (meaning put the red lead on the output of the stator and the black lead where it fasten too) put your meter on dc amps. Start your quad, turn all the accessories on. At the same time take another meter and measure the system voltage at the battery (doesn't matter where you measure it from, it's all common)

After getting these two numbers Volts X amps = watts

Check the rating of the stator (call the dealer or look in a service manual) If the actual wattage of your machine is more than 80% of the stators rated value the stator is to small.

This will give complete factual answers to this charging system delemmer.

 

You could say that the current was lower in those formulas and you would be right, BUT the measured voltage described above was the charging voltage for the battery (DC - output of the rectifier).Not the output of the stator which is AC.

Since the load on the rectifier is for the most part constant while charging the battery, its easier to determine current output than the AC part of the system. At 16 volts DC the current will most definitely be higher through the same load 14 volts DC was powering.

 

the voltage of the stator is close to the same of the voltage out put of the rectafier. the rectifier uses 4 diods wich uses .7 volts to braek the thresh hole of one diode. 4 X .7= 2.8 volts. so the stator runs 2.8 volts higher than the output of the rectifier. The battery acts as aholding tank and filters the highs and lows of the voltage, but in this case it either over charges or kills it. Meaning the battery can't take up for the broad voltage range that the machine is putting out. wich is either A) a bad regulator or B) a undersized stator.

Voltage will be the same where ever you measure it battery, rectifier, key switch, light bulb it doesn't matter. If thier is a voltage drop some where, just look at the upstream component and replace it, there is a problem with it.

The current will always be lower with higher voltage.

But any way lets not turn this into a electrical class thread.

 

You cant compare the AC voltage from the stator to the regulated DC output from the regulator. The voltage from the stator is not even close to being only 2.8 volts more than the regulated DC that charges the battery, it is alot more, in order to get a nice clean DC signal you have to have enough AC sine wave voltage to AVERAGE the DC signal, in this case the averaged voltage will be also alot more than the 13.5-14.5vDC, may be up near 18vDC unregulated. That Ac voltage is put across those 4 diodes which are only used to convert the AC to DC, they cannot regulate. The output of those diodes (18vDC)is put across the regulating circuit (zener?) where a solid 13.5-14.5 vDC is put across the load and the other 2.5 is put across a resistor.

Now that there's a nice clean regulated DC output toward the battery and rest of the quad you can make some observations - The output is supposed to be regulated at around 14vDC, the load should remain relatively constant other than turning on the lights after the quad is running and charging the battery.

The load is constant. Blackbirds regulator is obviously putting out more current since it destoys his battery, but also more voltage. I=E/R, it puts out more current because it has more voltage with the same load. Current will not allways be lower with higher voltage so long as the load stays the same and the supply is properly regulated.

When the lights are turned on the resistance decreases since the lights are in parallel to the battery. Trying to draw more current and lowering the overall voltage because the regulator isnt up to snuff to begin with it drops down to its somewhat normal operating range or 14.5vDC

 

I agree with you on most all of it. But what you are explaining is a healthy good charging system, I don't think this one is. I donn't know but to stop further electrical talk I will look at one friday and test it. I'll get back to you on it.

 

Well, with all those words you guys are bound to figure something out!
I'm sure the guys with problems appreciate any ideas. good discussion!

 

Whew, ten stories above my head. I do have a question though, It seems no one else on here has really had any kind of problem like this. So I wonder if Cannondale has tried to address the issue that a lot of people have had problems with stalling their machine too many times and having a dead battery, thus the quad might turn over but not start. What I'm trying to say is, my quad came out of the factory very recently, it is a 2003. Do you think they may have upped the output of the stator to try to maintain a full charge so there would be less chance of it going dead on the track? It seems fishy to me that both my quad AND my friends quad both have the exact same problem, they are 8 numbers apart, fresh out of the factory, and NO ONE ELSE HAS HAD THIS HAPPEN. What do you guys think? Also, if I keep running it like this, would it be detrimental to the machine, or is it just a matter of me probably getting stranded AGAIN?

Anyway, thanks for all the info!

 

Gaff,

Are you going to be able to check on a 2003 cdale? would be interested to see if they are all the same or borderline like these 2 with the lights and such, or check a 2002/1 and see what the voltages look like with lights on and off. good idea.

Blackbird,

Its possible they cranked it up a notch for 2003 to be sure the battery was topped out all the time, I read of a few guys that were having trouble at the starting line with batteries that werent fully charged. I would try and get a hold of cannondale themselves, they seem pretty cool about things. If you keep riding you may be ok with the lights on, if one blows out the others will go shortly there-after and you will be stranded again.