There have been a lot of posts about how to get 12VDC for GPS's, cell phones, etc., from a sled that has an AC electrical system. I thought I would post this to detail the most popular options.
1. Tap into the DC power for the APV or fuel pump circuits - while many have done this, I wouldn't. The reason is because these sources run through your ECU and any mistake or short could result in ruining your ecu. That's thousands of dollars retail that is being risked when there are other cheap solutions below. It is your choice though.
2. Build a 12VDC rectifier/regulator. This was the first way I did it and it worked well. The only drawback for me was that this only supplies DC power when the sled is running and my GPS can't switch automatically and shuts off. The cost (about $20) and time to build though is high enough now that there are other better solutions. If you like to tinker with electronics though, I have attached a circuit drawing of the one I built. I sold the sled and the home-built regulator went with it.
3. For those with starters on their sleds, hook up right to the battery for the starter. No brainer here and on my electric start sleds that what I do.
4. Use an aftermarket rectifier/regulator. There are many aftermarket rectifier/regulators out there that will work. I have found though that the ones for the pit bikes and little import ATV's are cheap and work well. Below is an e-bay link to one I put on my sons ATV last summer. It has 4 wires, 2 for hooking to the sled AC (yellow and pink), and 2 for the DC output (red is 12vDC+ green is 12VDC-). It costs less than $10 shipped to my door. I also put a picture in for when the link dies. Note: 2/23/2012 - based on my experiment with number 7 below, this regulator would also put out only about 6 volts at low rpm. This is a sled limitation due to the low rpm output of the stator lighting coil and is nothing wrong with the regulator. If you have to have 12V below 3000 rpm, you could add a 12V rechargeable battery like the snobunje type setup has. You would put the battery at the output of the regulator to get 12 below 3000 rpm to your accessories and the battery will get recharged when the sled is above 3000 rpm.
Voltage Regulator Rectifier For 200 250cc ATV Dirt Bike - eBay (item 330516668132 end time Feb-06-11 11:48:27 PST)
5. Install a snobunje type system that uses a separate small battery. Below is a link to the snobuje system. Cost $40
1075 ELECTRONIC ACCESSORIES POWER CELL
6. build your own snobunje type system and save about 1/2 the price. If you are cheap like me you can get an AGM alarm battery for about $10 and a 75 cent diode and wire one up yourself. As I said earlier I had previously made a regulator rectifier for one of my sleds, but my GPS turns off if I turn off the sled. I installed a battery into the sled that gets charged when the engine is running just like the snobunje setup. What I did was get a UB1213 sealed lead acid battery that is commonly used in alarm systems and installed it under the hood. The battery is about 3" x 1-1/2" x 2 ", weighs just over a pound, and can be installed in any position. I just velcro'd it in a corner I found where it would fit. I then tapped into the sleds alternating current. One lead goes straight to the negative terminal of the battery and the negative side of whatever your hooking up like the GPS or cigarette lighter socket. The other wire from the sled AC goes through a diode and then to the positive side of the battery and then to the positive side of the GPS or lighter socket. There is a quicky drawing I put together attached. You can get a diode at radio shack (I used a 3A 200 PIV rectifier diode-overkill). Do a google search for UB1213 and you can find the battery.
7. (Updated 2/23/2012) Well I did an experiment with the bridge rectifier and the capacitor and it worked as expected. Sort of. The "sort of" is because the output is less that 12V DC when my 2002 Mountain Cat 800 is idling. As near as my bad eyes could read my little analog voltmeter, it runs about 6 or 7 volts at idle (1500 rpm) and as soon as the idle is brought up to 3000 rpm or more, the DC voltage pops right up to 12V. Now according to my service manual, the lighting coil output should be about 7.0 to 7.7VAC at 2000 rpm, so after being rectified it should be 6.3 to 6.9VDC. That part compares pretty well with my experimental results. The service manual also says that the sled's AC voltage regulator is supposed to limit the AC voltage to 13.5VAC which will occur at about 3000 rpm. Plug that into the formulas and the rectified DC voltage should be 12.15VDC. This also compares well with my experimental results. The rectifier used was Radio Shack part 276-1152 (100V, 1500mA). You could use either part 276-1173 or 276-1146 to get a 4A output if desired. The capacitor in the circuit drawing below is to smooth the output so it more closely resembles true DC voltage. The capacitor I used was a 50W 100uF electrolytic capacitor, radio shack part number 272-1044. If you have to have 12V below 3000 rpm, you could add a 12V rechargeable battery like the snobunje type setup has. You would put the battery at the output of the rectifier to get 12 below 3000 rpm to your accessories and the battery will get recharged when the sled is above 3000 rpm.
EDIT #2: Number 8. Based on the post below by TallCool1, you could just install a rechargeable battery that isn't hooked to the electrical system of the sled and just take the battery in to the cabin to charge each night. See the post below by TallCool1 for more info on this option.[/COLOR]
Right now I have one home brew sno-bunje type setup and two wired right into the starting battery. Note: 2/23/2012 - My new favorite is number 7 above with a battery like the sno-bunje type systems.
I hope this helps someone out there
1. Tap into the DC power for the APV or fuel pump circuits - while many have done this, I wouldn't. The reason is because these sources run through your ECU and any mistake or short could result in ruining your ecu. That's thousands of dollars retail that is being risked when there are other cheap solutions below. It is your choice though.
2. Build a 12VDC rectifier/regulator. This was the first way I did it and it worked well. The only drawback for me was that this only supplies DC power when the sled is running and my GPS can't switch automatically and shuts off. The cost (about $20) and time to build though is high enough now that there are other better solutions. If you like to tinker with electronics though, I have attached a circuit drawing of the one I built. I sold the sled and the home-built regulator went with it.
3. For those with starters on their sleds, hook up right to the battery for the starter. No brainer here and on my electric start sleds that what I do.
4. Use an aftermarket rectifier/regulator. There are many aftermarket rectifier/regulators out there that will work. I have found though that the ones for the pit bikes and little import ATV's are cheap and work well. Below is an e-bay link to one I put on my sons ATV last summer. It has 4 wires, 2 for hooking to the sled AC (yellow and pink), and 2 for the DC output (red is 12vDC+ green is 12VDC-). It costs less than $10 shipped to my door. I also put a picture in for when the link dies. Note: 2/23/2012 - based on my experiment with number 7 below, this regulator would also put out only about 6 volts at low rpm. This is a sled limitation due to the low rpm output of the stator lighting coil and is nothing wrong with the regulator. If you have to have 12V below 3000 rpm, you could add a 12V rechargeable battery like the snobunje type setup has. You would put the battery at the output of the regulator to get 12 below 3000 rpm to your accessories and the battery will get recharged when the sled is above 3000 rpm.
Voltage Regulator Rectifier For 200 250cc ATV Dirt Bike - eBay (item 330516668132 end time Feb-06-11 11:48:27 PST)
5. Install a snobunje type system that uses a separate small battery. Below is a link to the snobuje system. Cost $40
1075 ELECTRONIC ACCESSORIES POWER CELL
6. build your own snobunje type system and save about 1/2 the price. If you are cheap like me you can get an AGM alarm battery for about $10 and a 75 cent diode and wire one up yourself. As I said earlier I had previously made a regulator rectifier for one of my sleds, but my GPS turns off if I turn off the sled. I installed a battery into the sled that gets charged when the engine is running just like the snobunje setup. What I did was get a UB1213 sealed lead acid battery that is commonly used in alarm systems and installed it under the hood. The battery is about 3" x 1-1/2" x 2 ", weighs just over a pound, and can be installed in any position. I just velcro'd it in a corner I found where it would fit. I then tapped into the sleds alternating current. One lead goes straight to the negative terminal of the battery and the negative side of whatever your hooking up like the GPS or cigarette lighter socket. The other wire from the sled AC goes through a diode and then to the positive side of the battery and then to the positive side of the GPS or lighter socket. There is a quicky drawing I put together attached. You can get a diode at radio shack (I used a 3A 200 PIV rectifier diode-overkill). Do a google search for UB1213 and you can find the battery.
7. (Updated 2/23/2012) Well I did an experiment with the bridge rectifier and the capacitor and it worked as expected. Sort of. The "sort of" is because the output is less that 12V DC when my 2002 Mountain Cat 800 is idling. As near as my bad eyes could read my little analog voltmeter, it runs about 6 or 7 volts at idle (1500 rpm) and as soon as the idle is brought up to 3000 rpm or more, the DC voltage pops right up to 12V. Now according to my service manual, the lighting coil output should be about 7.0 to 7.7VAC at 2000 rpm, so after being rectified it should be 6.3 to 6.9VDC. That part compares pretty well with my experimental results. The service manual also says that the sled's AC voltage regulator is supposed to limit the AC voltage to 13.5VAC which will occur at about 3000 rpm. Plug that into the formulas and the rectified DC voltage should be 12.15VDC. This also compares well with my experimental results. The rectifier used was Radio Shack part 276-1152 (100V, 1500mA). You could use either part 276-1173 or 276-1146 to get a 4A output if desired. The capacitor in the circuit drawing below is to smooth the output so it more closely resembles true DC voltage. The capacitor I used was a 50W 100uF electrolytic capacitor, radio shack part number 272-1044. If you have to have 12V below 3000 rpm, you could add a 12V rechargeable battery like the snobunje type setup has. You would put the battery at the output of the rectifier to get 12 below 3000 rpm to your accessories and the battery will get recharged when the sled is above 3000 rpm.
EDIT #2: Number 8. Based on the post below by TallCool1, you could just install a rechargeable battery that isn't hooked to the electrical system of the sled and just take the battery in to the cabin to charge each night. See the post below by TallCool1 for more info on this option.[/COLOR]
Right now I have one home brew sno-bunje type setup and two wired right into the starting battery. Note: 2/23/2012 - My new favorite is number 7 above with a battery like the sno-bunje type systems.
I hope this helps someone out there