12v or 3v to run a gps

Got questions? We got answers....
Post Reply
pwdice
Member
Posts: 1
Joined: 11:55 pm Sep 03 2008
Country:
Location: painesdale, mi

12v or 3v to run a gps

Post by pwdice »

I'm wanting to rig up a way to run my gps for long periods of time on non-battery save mode. I can rig up a mount for the gps, but does anyone know off hand what the lighting coil voltage is? is it regulated?

I'm basically wanting to add a cigarette lighter to the bike.

96kdx200
User avatar
fuzzy
KDXRider.net
KDXRider.net
Posts: 3437
Joined: 01:29 pm Jun 18 2003
Country:
Location: Fredneck, MD

Post by fuzzy »

12v AC, rectified to DC. Output from coil will vary....Just like an alternator. Might be better off creating a LiIon pack.
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Diagram for an H2 ('96):

Image

The lighting coil output voltage is certainly AC..and, as asked, its output can be in excess of 100V.

The regulator in the circuit is an AC regulator. The bike lights run on AC, that in the area of 13VAC or so.

Besides all the AC DC stuff..the OEM system output is in the 35W range. It's barely enough to run the lights, let alone any accessories.

Might be better off with a LiIon pack. :wink:

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

I was planning on turning the AC from the lights into DC (with a rectifier and linear regulator) and then running the Trailtech Vapor. Tonight I checked the voltage with an AC meter and it was around 4VAC even when I revved it up (of course that is RMS). So that is a bit lower than I thought it would be.
User avatar
TWMOODY
Gold Member
Gold Member
Posts: 752
Joined: 08:10 pm Dec 01 2006
Country:
Location: Southeast , Michigan

Post by TWMOODY »

Hope you get a free bottle of asprin with that vapor!
You will need it .............
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

>|<>QBB<
TWMOODY wrote:Hope you get a free bottle of asprin with that vapor!
You will need it .............
If I can get enough AC voltage to convert and linear regulate to DC it should be like running off of a battery and not have the noise that causes tach noise. I guess it is caused by the fact that the AC supplied to the light has frequency that varies with RPMs.
User avatar
TWMOODY
Gold Member
Gold Member
Posts: 752
Joined: 08:10 pm Dec 01 2006
Country:
Location: Southeast , Michigan

Post by TWMOODY »

Poor shielding and isolation between circuits.
You can forget hooking up any power source from the bike.
The coolant temp sensor mounts perfectly between the rads under
the tank.
You can tap the hot lead for the coil at the connector on the right side of
bike just under the fnt of the seat.
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

I know that it is noisy. But I have filtered a switching regulator (very noisy) enough to be used in very low noise analog signal processing environments (a bridge circuit reading a load cell in to a high gain instrumentation amp). I just need to look at it on a scope and see how the power looks and then rectify and then filter the hell out of it with capacitors and then use a linear regulator. Then pot the entire circuit in a thermally conductive, electrically insulating epoxy. But maybe I'm wrong :grin:
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Who was it that tried hooking a Vapor unit up to the exciter (ignition) coil? Someone did..at Endurance's rec. It din't work........

RE: 'But maybe I'm wrong...'

Somebody's bein' a smarta$$................... :wink:

4VAC sounds pretty low..root-mean-square or not. I don't know what my meter 'says'..maybe peak..but it's surely NOT 4VAC RMS. At .7 peak, you wouldn't get 4RMS from anything I've ever measured on my bike..and I've HAD a 'scope on it.

Something's not right about that.

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

I put a scope on the signal going to the lights and this is what I got at idle
Image

and revved up to moderate rpms

Image

so the signal looks pretty good. Not noisy at all. But the peak to peak voltage is only 15.2 to 16.4. So even using a schottky bridge rectifier (low voltage drop) its going to be difficult to get more than 7.7 volts out of it. So I guess I will use an adjustable linear regulator and set it for about 6 to 6.5 volts output which is the minimum the vapor will run off of.
User avatar
fuzzy
KDXRider.net
KDXRider.net
Posts: 3437
Joined: 01:29 pm Jun 18 2003
Country:
Location: Fredneck, MD

Post by fuzzy »

Well, you're smarter about this stuff than the people your asking (myself anyway)...Good work! Post your setup so others can plagiarize...
'91 KDX 200 Project $300 KDX
'95 KDX 200 Project $600 KDX
'94 WR 250 Always a project
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

..so the signal looks pretty good. Not noisy at all. But the peak to peak voltage is only 15.2 to 16.4. So even using a schottky bridge rectifier (low voltage drop) its going to be difficult to get more than 7.7 volts out of it.
:hmm:

Really.

I'm not an electrical engineer..but that sounds pretty unlikely to me.

Consider a 'one-each' full wave supply using 7x15s with a 16VAC input:


'...With 16V, you can easily get +/-15V DC regulated...'


And that's at 60Hz/16ms period! Your idle freq is 82.24.

Now...before you go off on how to measure AC and all, I do realize the above link isn't any kind of exact reference to what you're after. My point is the full wave part of it, and the losses involved.

No one says 'ground' has to be metal/frame/0V. It's merely a reference that can be whatever you WANT it to be. If 'ground' is -6VDC and 'power' is +6VDC...you've got a 12VDC differential. Also, if you're thinking AC theory and assuming 60Hz..you're going to get a lot more pulses than that out of an engine turning thousands of RPM which means the capacitance required to filter/store the input is less..the output will be more stable (which is pretty much saying the same thing twice).

I think there have been successful Vapor installs on KDXs. Once the one noted above took power off his lighting coil as opposed to the exciter (sparky) coil, I think it worked OK. AZRickD, it was.

Read THIS.

Info there on a wide range AC/DC input supply, for one thing. I don't see that Rick ever got it all sorted out, though. I'm not sure where he ended up with his.

Why not use a battery, anyway? A 2032 runs Trail Tech's Endurance for years. At least, I haven't changed the battery in one that is several years old..and it still works (battery-wise. It does have a button that quit working a long time ago).

Using Google I got a fair amount of info from other Vapor users (on TT for example). Seems there is a lot of trouble with that model in the first place when it comes to finding a 'good' power source

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

Of course you are right about getting 15V out of 16VAC if you are not doing full wave rectifying. I just have some full wave rectifiers laying around and do not have any negative regulators laying around, and if you do that, then you have a 8V rectified signal (if you neglect diode drops). But the link you supplied regulates 1/2 of the AC signal to a +7.5V and the other to -7.5V so you get 15V total.
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

..do not have any negative regulators laying around..
I think they're still available, though. You could get one.... :wink:

What do you need a negative regulator for, anyway (if you use diodes configured in a bridge)? Float the common, use a positive regulator.



Image


No?




A btw for the folks wondering why ANYone would be interested in rectumfriars, this is a pretty good write-up about that sort'a stuff.

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

Yeah, your right about the negative regulator. I wasn't thinking. And yes, negative regulators are readily available, I just was trying to build with stuff I already had.



But one thing, the guy in the article you posted wtih the +/- 15V supply is using 16VAC, but that is more ke 22V pk because likely the 16VAC is an RMS value. The RMS reading of the signal I posted would be more like 5.5VAC RMS (8Vpk/1.414).

Another thing, I am not sure about the internals of the Vapor. I am not sure if having GND at (for example) -6V would screw up the coil tach reading. It would likely be fine, but I just don't know how their tach sensor works. Plus I am trying to get as clean of a supply as possible, so using the chasis ground might work best. If I can get a solid 6V-7V at idle, then I will go with that. If not, then I will try the +/- design and run the ground as the -.
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

>|<>QBB<
lemmy wrote:Yeah, your right about the negative regulator. I wasn't thinking. And yes, negative regulators are readily available, I just was trying to build with stuff I already had.
I was just messin' with you.


>|<>QBB<
lemmy wrote:But one thing, the guy in the article you posted wtih the +/- 15V supply is using 16VAC, but that is more ke 22V pk because likely the 16VAC is an RMS value. The RMS reading of the signal I posted would be more like 5.5VAC RMS (8Vpk/1.414).
Which is exactly why I said: ' Now...before you go off on how to measure AC and all, I do realize the above link isn't any kind of exact reference to what you're after. My point is the full wave part of it, and the losses involved. '

:wink:


>|<>QBB<
lemmy wrote: Another thing, I am not sure about the internals of the Vapor. I am not sure if having GND at (for example) -6V would screw up the coil tach reading. It would likely be fine, but I just don't know how their tach sensor works. Plus I am trying to get as clean of a supply as possible, so using the chasis ground might work best. If I can get a solid 6V-7V at idle, then I will go with that. If not, then I will try the +/- design and run the ground as the -.
Ask 'em.

As I understand their design, the power input has nothing to do with the RPM sensor input. Besides, I don't understand how it could!, either.. You don't want ANY reference to tie from something that is putting out tens of thousands of volts into a lighting/logic circuit.


Something I do find odd: Their recommendation is to NOT tie into regulated power. Did you read that in the TT post? Supposedly the switches in such circuits bounce, and that causes grief for the logic. They DO say to connect to the STATOR side. The Vapor is supposed to work with either AC or DC..so whether your lights were on or not, (if on, you would get regulated AC, if off you would get UNregulated AC), the waveform type would be as required.

But...with the switch off, you get LOTS of volts..over 100. I dunno if the Vapor could handle that. But that IS what they suggest.

Talk to 'em. tech_support@trailtech.net I believe is what you're after.

Ask them if the Vapor can handle UNregulated AC. They should know if the Vapor will run on pre-regulated power on the KDX.

It's possible to have a light switch simply turn on the lights...to have it switch 'on' already regulated power. That is NOT what the light switch does on the KDX. It does switch on the lights...it also switches 'on' the regulator.

Let us know what they say?





BTW...my 'scope is a quite old Tektronix 465 (I think) with the channel 2 vertical controls busted off..and parts no longer available. I wouldn't know what to do with a 'scope that TOLD me freq, period, amplitude, and from your pics allows you to segment the part of the waveform you want that information on. Your pics look more like a waveform analyzer than a 'simple' sillyscope to me.

Maybe 'lectrons and 'lectricity haven't changed over the years, but the way you can LOOK at either of 'em sure has.

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

I agree that you wouldn't want anything from the tach circuit tied in to the power supply. But I know TWMOODY had problems with the tach when he hooked up power from the lights.

The VAPOR claims 6-400 VDC/VAC inputs with polarity not being an issue. But in another place they claim 9-400 VDC/VAC. Also, it does say in the manual to connect to the stator, but then on the phone they say to connect to the light side of the light switch to get better regulated voltage.

If the unit is capable of taking AC like it says, I can't see why the light voltage would cause any problems. The AC waveform is very clean as you can see from the scope screen grabs. The only thing I can see is I wonder if some people are just wrapping the tach wire around the spark plug wire (red and black) instead of pull the black of separately and grounding it? I actually pulled the black off and grounded it on the upper coil screw. Then I took the red wire and hooked it to the blue wire coming from the CDI unit to the coil. The tach was very steady, but the vapor was running off of the internal battery.

My personal scope is an old 465 too. I had to replace one of the electrolytic capacitors to get it to work. But it is still not in good shape. The screen grabs I sent came from a nice Tektronix TDS200B digital storage scope that I borrowed from work:

Image

They are very easy to use and portable (very light).
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

We're going around in some circles...compliments of Trail Tech, it seems.

They have said both..power before the switch, power after the switch..each with a reason as to why it has to be that way.

How to place the tach sensor wiring has been said to go both ways, each being the wrong way when the other was said to be correct.

Some have had trouble with the black wire on the coil fastener, resolved the problem when they bolted it directly to the frame.

Running on the internal battery has been a problem for some, running on external power has been a problem, too.


One thing that does seem to be a common thread..and already said:
TWMOODY wrote:Hope you get a free bottle of asprin with that vapor!
You will need it .............
This started out being a GPS thread...got hijacked.

Did the original questions get answered satisfactorily? Lighting coil voltage is regulated AC (light switch 'on'), 15-16V.

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
lemmy
Member
Posts: 221
Joined: 12:36 pm Jul 25 2008
Country:

Post by lemmy »

Yeah, trail tech said not to use the internal battery, even though their manual says it is perfectly ok.

My ground wire for the tach sensor is connected directly to the frame at the coil.

Yes, I guess I did hijack. Sorry to the OP.

One thing I did check is the regulated voltage with no lights hooked up (headlight or tail). It was an extremely noise signal that didn't resemble a sin wave at all. I guess like many switching regulators, it needs some sort of load to operate properly. I took a screen grab of that too if anyone wants to see it.
Post Reply