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f76
03-19-2015, 07:41 PM
I recently installed a LED light bar on my 350x with the intent of just running it off of the regulated AC power of the alternator. However after numerous warning comments about ruining the light bar from AC power, I've decided to convert over to DC power for the lighting circuit. Anybody have any experience with this?
I called Ricky Stator and inquired about this rectifier/regulator (http://www.rickystator.com/product/other-parts/item/single-phase-rectifier-regulator) and was told it work without having to float the ground off the alternator. Instead the lights would have to be grounded to the battery or capacitor and not the frame. I also asked about this capacitor (http://www.rickystator.com/product/other-parts/item/capacitor). It would work in place of a battery except it may flicker at idle which isn't going to be a big deal to me.
The rectifier/regulator would come with instructions however I'm more curious about the floating ground. Has anyone done this on a 350x and would like to help me out with the procedure? I'm comfortable with wiring and such however I'm not too keen on exactly where to wire in the rectifier and capacitor. I'm open to all suggestions and advice. Thanks!
Wiring diagram for a 350x below. Apologies for the sideways orientation.
212617

UPDATE

I finally finished up my ac to dc conversion using the above mentioned parts from Ricky stator and have some pictures to share. Long story short here is how I wired it up: two lighting circuit wires coming off of stator-> trail tech reg/rec-> capacitor-> lights. I grounded the lights to the capacitor, not the frame. I undid the wiring harness and reused the ground wires, just clipped them from the rest of the grounds. All in all simply process, just daunting if doing it the first time for fear or ruining something.
http://images.tapatalk-cdn.com/15/04/15/2fe0a6f7c11254e8fa74444af2a4c301.jpg
The wiring looks nothing like the diagram and serves only as a guide.
http://images.tapatalk-cdn.com/15/04/15/92086874f8285e6235b7554b0d75c5aa.jpg
http://images.tapatalk-cdn.com/15/04/15/50160576ff63d490481ca3193c0c3bd5.jpg
http://images.tapatalk-cdn.com/15/04/15/04c9632103cc4a5874d5f4886f73f7c0.jpg
http://images.tapatalk-cdn.com/15/04/15/3937e43792b4f2e7cc87b067ade4ffe9.jpg
Thanks for all the help to everyone who gave advice! After driving a short time the capacitor was charged and the lights didn't flicker at idle. I'm very pleased with the conversion and the light bar is quite bright!

YTZ drew
03-20-2015, 04:55 PM
All LED's are in fact diodes, so they technically should have no problem with AC (basically they will light up when one half of the AC sine wave forward-biases them, and not light up when the other half of the wave goes by). But if you want to feel better about it, just connect a single rectifier diode in line with your light bar. That will result in half-wave rectified AC, basically DC that is less smooth then full-wave rectified AC, but DC nonetheless.

deathman53
03-20-2015, 07:29 PM
I have a led tail light for one of my atv's. I was told it will work on AC, but with have about 1/2 the brightness, didn't concern me too much. Being that its a only used on the track and it is just for the taillight and brake light. For headlight, use a full wave reg/rec and a capacitor or small battery. Yes, it will work w/o but you will lose alot of light and you are already modifying your electrical system, might as well do it right the first time.

YTZ drew
03-21-2015, 09:39 AM
I think you would only have a slight decrease in light output, and only at low engine rpm's. The half wave rectification won't give you less voltage, it just clips the bottom half of the sine wave off rather than flipping it over.

If you want full wave rectification, you need to run a separate ground wire to whatever accessory you intend to supply with DC. The stator output lead and chassis ground are the inputs to the full wave rectifier, and the negative DC output of the rectifier must not be connected to the chassis (IE- "floating" the ground)

Xpress
03-21-2015, 10:37 AM
Running LED's on AC voltage can actually damage them and decrease light output as well as their rated life expectancy. AC power they basically turn on and off hundreds of times per second so multiply that by the course of an hours worth of riding and suddenly you have turned that light on or off close to the millions.

Converting to DC power is actually pretty simple. When they refer to 'floating the ground' they just mean you have to remove the alternators ground from the frame and instead ground it directly to the regulator rectifier. Typically a lighting coil on a bike has 2 power wires coming out of it to power the bike- one that gets grounded to the frame, and one that is ran to the lights. The TrailTech Regulator Rectifier is the best aftermarket unit available IMO that's inexpensive, so I will recommend and reference it here. You basically run both of the alternators output wires to the reg/rec unit, then run the 2 wires coming off of the reg/rec to a battery or capacitor (a battery is always preferred). The battery acts as a filter for the system so you only pass on clean power to your lights. Now all you have to do from here is hook up your LED lights to a switch and run the power wires for that switch to the battery. Since the 350x has a good lighting coil inside of it, you should have plenty of power to keep the battery topped off (the reg/rec will automatically dump excess power so it doesn't overcharge the battery) and power plenty of lights- up to about 110 watts of lighting, which is a LOT of LED lighting.

The other advantages to a DC system with a battery is you will have a constant flow of power to your stock headlight so it should remain bright at all times, rather than dim when the RPM's drop to idle.

Frankencelery
03-21-2015, 11:10 AM
I have particular interest in this subject. Check out THIS (http://www.3wheelerworld.com/showthread.php/167776-Tecate-LED-Headlight-Project-*almost*-Complete-PICS!?highlight=tecate+led) thread where I put LED lights on my Tecate. Interestingly, I got the same bit from Ricky Stator about having to float the ground on the stator, but it wasn't true, at least not with the Trail Tech regulator. I used frame ground for one of the AC input wires, but did NOT use frame ground for the DC output. So the output is floated, I guess.

A lot of people say you can feed AC right into LED lights. The two times I have tried it, once with the Tecate headlight and once with an ATC70 tail light, the lights have blown. The 70 taillight lasted a long time, and it really should have had no problem, since it was a 12v LED plugged into a 6v system. The difference is that in both cases, I was feeding UNREGULATED AC into the LED, and I think that's a killer for sure. Despite that, I will always regulate AND rectify from now on, which is what makes the Trail Tech a perfect fit.

One last thing.....I did use a capacitor at first, but later upgraded to the Trail Tech battery when the capacitor failed. It has kinda funny behavior. The headlight still doesn't come on until the engine is kicked over, and then it's got a timer, so if you shut the engine off, the lights stay on for 10 seconds or so. Sorta like my wife's car...:lol:

f76
03-21-2015, 01:29 PM
Thanks for the help gentleman! I plan on grounding to the rec/reg and ditching the idea of floating the ground off the stator. I only plan on wiring in my light bar and a tail light so two grounds to the rec/reg won't be difficult. Meow I just have to spend the money for the rec/reg and a capacitor...

YTZ drew
03-21-2015, 01:33 PM
Running LED's on AC voltage can actually damage them and decrease light output as well as their rated life expectancy. AC power they basically turn on and off hundreds of times per second so multiply that by the course of an hours worth of riding and suddenly you have turned that light on or off close to the millions.

Converting to DC power is actually pretty simple. When they refer to 'floating the ground' they just mean you have to remove the alternators ground from the frame and instead ground it directly to the regulator rectifier. Typically a lighting coil on a bike has 2 power wires coming out of it to power the bike- one that gets grounded to the frame, and one that is ran to the lights.

You are correct about the half-wave rectified DC (or straight AC) turning on and off all the time. I suppose that would tend to aggravate some LEDS. I wonder how the new LED replacements for household bulbs are doing it? But, a large capacitor (~500uF) connected across the LED light bar should take care of that for the most part.

I haven't tried this on a 350X, but from the wiring diagram it looks like one end of the stator coil is grounded at the engine, not by a remote wire to the frame, but I could be wrong. If its grounded right at the stator, that would be difficult to disconnect, as it wouldn't have a wire lead, just a small piece of copper wire grounded right at the pole piece. If it has an external wire, then you are correct, ungrounding it and connecting it into the rectifier is the best way to go. Only problem is, the stock 350X regulator is designed to work on AC, so that would also have to be removed. If you float the ground after a full wave rectifier, you can leave the stock regulator alone, and if you are still running a regular incandescent bulb somewhere else on the trike it will be unaffected. Both ways work, just a matter of preference I guess (and if you want to run separate ground wires or not).

YTZ drew
03-21-2015, 01:35 PM
Oops, looks like you and I posted at about the same time F76.

Xpress
03-23-2015, 10:08 AM
Keep in mind that if you don't float the ground, you still have a partial AC system being grounded to the frame- not a clean DC system. It sounds difficult- it would take all of 10 minutes to do ;)

f76
03-23-2015, 08:53 PM
Are you talking about floating the ground off the stator or floating the grounds of the lights to the rectifier/regulator?

KIM 501
03-24-2015, 06:44 AM
I bought gensisi 36watt led w/cree led-when I plugged them into headlight wires they were dim ,throttle up got brite and at high rev went out,plugged them into tail light and they work perfect-WHY? it is a 350x

Xpress
03-24-2015, 10:05 AM
Are you talking about floating the ground off the stator or floating the grounds of the lights to the rectifier/regulator?

Float the ground off the stator. Once the power goes through the reg/rec then you can ground it to the frame. That way you'll have DC power everywhere on the bike.

f76
03-24-2015, 10:14 AM
That route would be easier in the long run and for potentially adding more lights down road too. However ignition system runs ac and I don't want to mess with that by potentially screwing up the ground for that system. If I have this all thought out properly in my head (good luck right?), I intended to leave the ignition side of the electrical system untouched and running ac. The lighting circuit would then be converted to dc with my light ground going back to the reg/rec and hopefully eliminating the need to float the ground off the stator. I appreciate the help Xpress, I'm going out on a shaky limb here for my electrical knowledge.

Varget22
03-24-2015, 02:44 PM
The stator in your bike has three separate coils. One runs the ignition and you can leave that one alone. There is a second coil that is running your lights with AC. There is a third coil that is grounded and does nothing in stock configuration. When people say to float the ground they are talking about removing the ground connection from the third coil. You can connect a yellow wire to this coil and route it with the other yellow wire from the second coil to get two phase AC that can be fed into rectifier/regulator. Do not use the frame for a ground, it will allow AC back into your lighting circuit. You can also find a rectifier/regulator that is designed for single phase and just run the one stock yellow from the one used lighting coil to it. This will work but you will have about half the available power that you would have with the two phase configuration. I did this on a 85 250r with HID lights and LED tail light. I also installed a battery to allow lights to run with motor off and it cleans up the DC big time.

Pickup_man
03-24-2015, 04:53 PM
Make mental notes on how you do this, or give me a call when you do it. If it really is as simple as people say it is I'd be interested in doing this to mine and would love the help. Hopefully that'll give me a bit more light too.

RubberSalt
03-26-2015, 01:17 AM
You guys have over complicated this. Converting AC to DC is ULTRA SIMPLE. You just need a diode bridge :). AC goes in, DC comes out. http://en.wikipedia.org/wiki/Diode_bridge . This is the part: http://www.ebay.com/itm/Bridge-Rectifier-1ph-35A-1000V-35-Amp-Metal-Case-1000-volt-35A-Diode-FL-USA-/281275599199?pt=LH_DefaultDomain_0&hash=item417d55095f

This only converts it to DC, it does not regulate the voltage. Keep the AC voltage regulator, feed that into the Bridge... and regulated DC up to 35 amps! http://www.ebay.com/itm/Trail-Tech-AC-Voltage-Regulator-7003-AC01-/191502468358?hash=item2c966fc506&vxp=mtr

Lighting coil -> ac regulator -> bridge -> 12v out! -> battery/capacitor recommended for power smoothing.



This style bridge is classified as a full wave rectifier. The output is DC, but it's not a constant DC. The wiki article explains in more detail. A battery or capacitor will smooth this out. I recommend super caps (Heres a 10 farad pack http://www.ebay.com/itm/SUPER-CAPACITOR-BANK-16-2V-5F-New-/111625535062?pt=LH_DefaultDomain_0&hash=item19fd667e56_ opposed to batteries(unless you need electric start). They charge in a matter of seconds, can discharge 100% hundreds of thousands of times, their smaller, and they way considerably less than lithium ion or lead acid. A 350 farad Pack http://laserhacker.com/?p=110.

RubberSalt
03-26-2015, 03:31 AM
I've just purchased a capacitor bank and an ac voltage regulator. I've already got a few 50 amp bridges. I'll post up a thread if I get it all working correctly. I'll be doing this on an 84 Tecate. :)

f76
03-26-2015, 11:04 AM
Do you have first hand experience with this method? I'm on a tight budget for this and want to purchase parts once. Obviously there are different methods of converting but if you're correct, the method you described appears to be the easiest and cheapest. I would like to see or hear about some actual working setup for my application. Thanks for the suggestion!

Xpress
03-26-2015, 10:54 PM
With a bridge rectifier you would still need a voltage regulator to help smooth out the power, otherwise you could potentially wind up with power spiking to 50v+ which can easily short out certain lights. The regulator/rectifier from TrailTech has both of these items built into it and at 50 bucks it's an inexpensive option. The other option is to use a regulator/rectifier from some other modern motorcycle that would be a bit more efficient than the TT unit but that's another story. Ultimately it's up to you. Converting to DC power is literally as simple as it sounds, there's almost zero complication with it.

I myself prefer to run a battery in the event the engine dies for some reason, that way I'm not stuck totally in the dark. That and I tend to put glowy LED's underneath to turn on while the bike is parked at camp :)

Regarding the coils- one set is for powering your lights, and another set is for powering your ignition. They are not electrically connected in any way. The ignition tends to be the smaller of the 2 and is easy to identify because it's generally wrapped in some material. The lighting coils tend to be exposed copper. Just follow the leads off of the stator to the component they power and you will find out which does what.

RubberSalt
03-29-2015, 09:55 PM
I want to say the 350x has a 12v AC regulator.

Everything is in the mail, I'm testing this on my Tecate. Picked up the 80w ricky stator (they recommend a regulator), the 5 farad capacitor back rated up to 16.2 volts, and the trail tech AC voltage regulator. I've already got the bridge rectifiers.

Total damage:
Ricky Stator (http://www.rickystator.com/product/stators/kawasaki/kawasaki-tecate-3-80-watt-stator), $125
Trail Tech voltage regulator (Adjustable voltage): (http://www.ebay.com/itm/Trail-Tech-AC-Voltage-Regulator-7003-AC01-/191502468358?hash=item2c966fc506&vxp=mtr)$17.95
5 Farad Capacitor back (http://www.ebay.com/itm/111625535062?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT): $13.25
Diode Bridge (http://www.ebay.com/itm/KBPC5010-1000-Volt-Bridge-Rectifier-50-Amp-50A-Metal-Case-1000V-Diode-Bridge-KA-/261623326473?pt=LH_DefaultDomain_0&hash=item3ce9f72709): $ 3.49
-------------------------
Without stator: $34.69
With stator: $159.69

oscarmayer
03-31-2015, 09:31 AM
can we not just get a regulator/rectifier from a Honda of some sorts like off a 400ex or something and do the same?

f76
04-15-2015, 09:26 AM
Added update progress and pictures.