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Discussion Starter · #1 ·
2000 Polaris XC 700 Deluxe , i wan to install 12-24 DC 120 watt 10 amp LED's.

Should i get the power from stator or the voltage regulator ? Whats the max load on the voltage regulator ? Maybe ill get a second regulator ?? What would be the spec's of another regulator be?

then after the VR ill do the 50V 25A Bridge Rectifier > capacitors for evening out> Fuse 10 amp>LEDS

is that reasonable ?
 

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Yes, as sketched will work. Though the lights may flicker and may even go out at the lowest rpm and/or highest rpm depending on what the LED components are included. The capacitor will smooth (filter) the power pulses but it will not hold voltage constant. Voltage will go up/down with engine rpm.

The improvement would be to put a small battery in place of the capacitor. Wired the same, in parallel to the light NOT in series. The benefit of the battery is stable voltage. It will sink high voltage when engine is at high rpm and will boost low power/low voltage to the light when engine is low rpm. It does not have to be large. A simple cheap 2 amp.hr SLA will doo. Basically, a battery is a voltage regulator and capacitor in one black box, with some power reserve as bonus.

For consideration.
 

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The power rating of the regulator is made to dissipate all the power the stator puts out (ie, non-factor when figuring out what you are doing).

Your circuit drawing will work just fine. The lights might flicker a little bit at lower RPM. It really depends on the size of the CAP you put in there. Bigger it is, the less flickering.

No battery needed.

Just a note: Voltage does not change with the RPM of the motor if the regulator is doing its job. Well, okay, technically it does vary a little, but only up to the maximum. The variance range is usually 11 to 13.5 volts. What does change is the frequency of the AC signal coming from the stator. On an Arctic Cat Z 370, at idle (about 1000 RPM) the frequency of the output was about 120 hz. (I used just a diode, so my output was only a pulsating DC-half wave. So the light flickered at 60 hz. Bridge rectifier would have made them flicker at 120hz, which is mostly discernible to the human eye.

I only wished I would have put a fuse inline, because I think the regulator went bad and it burned up the LED circuit board.
 

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ps. Battery won't bring a voltage down. It will hold it from going lower than the battery. Any over voltage is just cooking the battery.


As for a sleds regulator... The stator is always putting out the maximum power it can put out given the RPM. If the power is not used in lights, heated grips, etc, it is dissipated by the regulator. The regulator is connected in parallel with the AC system.

So adding other accessories to the accessory circuit actually helps the regulator as it does not have to dissipate as much.

For those who don't believe me, try disconnecting your accessories (lights, grips, misc), go drive the sled around for about 15 minutes and then touch your regulator. I guarantee it will be very warm or hot.
 

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Discussion Starter · #10 ·
ps. Battery won't bring a voltage down. It will hold it from going lower than the battery. Any over voltage is just cooking the battery.


As for a sleds regulator... The stator is always putting out the maximum power it can put out given the RPM. If the power is not used in lights, heated grips, etc, it is dissipated by the regulator. The regulator is connected in parallel with the AC system.

So adding other accessories to the accessory circuit actually helps the regulator as it does not have to dissipate as much.

For those who don't believe me, try disconnecting your accessories (lights, grips, misc), go drive the sled around for about 15 minutes and then touch your regulator. I guarantee it will be very warm or hot.



how much can a voltage reg can process ? like how many amps ? the OEM one.
 

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how much can a voltage reg can process ? like how many amps ? the OEM one.
I think the max voltage of the regulator is something like 80 volts AC. By the nature of the way it works, the voltage should never go above ~14 V.

It doesn't handle any amperage, per-se. Meaning, how much the rest of the system draws doesn't matter to the sleds VR, it only matters to the stator itself. By the way it is made, even shorting the stator output will not harm the stator. The stator, typically 280 watts, will simply drop the voltage if you draw more than 280 watts.


I do want to mention, VRs for sleds with batteries have a 12 volt pulsating DC output (the red wire). Typically this can only handle 5 amp output and drawing more than that will damage the VR.
 

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I'd put something like a 50 volt 47uf. Should be about the size of a D battery.

Smaller works though. Even two smaller ones in parallel would work.
 

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Thanks, yeah but I can't really use electrolytics, I'm looking for some kind of bulletproof, military proof thing that will be happy living under the hood of a 2 stroke.
 

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Just silicone the heck out of it. That is what BRP is doing with theirs. Even the "Shot" is simply a capacitor bank, all siliconed into a brick.
 

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Just silicone the heck out of it. That is what BRP is doing with theirs. Even the "Shot" is simply a capacitor bank, all siliconed into a brick.
Yeah that's one approach. Maybe I'm just being too finicky. I was looking for robustness and low sensitivity to temperature swings. But at the end of the day, it's just hopefully reducing flicker. It's not doing anything especially precise. Thanks for the tip!
 
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