battery charging

[Chris Krok]

> If you have > a bad connection somewhere in the line, it will lower the voltage > hence drawing more amps and burning things up. We had a pretty > intensive inspection program on the drilling rigs that I used to > work on offshore. Checked all major circuit connections monthly with > heat seeker infared guns. It's amazing the damage a bad connection > will do.

A bad connection creates a local spot of high resistance, which lowers the voltage at the load. The resistance also lowers the amount of current flowing through the circuit, and resistive heating will occur at the bad connection (wattage going to heat = I^2 * R). This is what causes melted connections, fires, etc. Since the heat output goes up with the square of current, it doesn't take much of a resistance to cause a problem. With typical resistive devices, the current draw goes down with lower voltages, rather than up. However, the case might be different for motors, and maybe that was an additional concern on the rigs. Glenn, I'll second Devon's suggestions. Make sure there really is only 14-14.5 volts at the lamp, and then check for vibration problems. Krokko -- Dr. J. Christopher Krok John Lucas Adaptive Wind Tunnel Caltech MS 205-45, Pasadena, CA 91125

[Bogdan Swider]

Gentlemen - I know I'm using the word loosely-, In the conditions/circumstances you describe why doesn't the fuse blow before the bulb burns out ?? Bogdan, who's trying add to his paltry electrical knowledge by playing ask the rocket scientist and oil rig worker

> > If you have > > a bad connection somewhere in the line, it will lower the voltage > > hence drawing more amps and burning things up. We had a pretty > > intensive inspection program on the drilling rigs that I used to > > work on offshore. Checked all major circuit connections monthly with > > heat seeker infared guns. It's amazing the damage a bad connection > > will do. > > A bad connection creates a local spot of high resistance, which lowers > the voltage at the load. The resistance also lowers the amount of > current flowing through the circuit, and resistive heating will occur at > the bad connection (wattage going to heat = I^2 * R). This is what > causes melted connections, fires, etc. Since the heat output goes up > with the square of current, it doesn't take much of a resistance to > cause a problem. > > With typical resistive devices, the current draw goes down with lower > voltages, rather than up. However, the case might be different for > motors, and maybe that was an additional concern on the rigs. > > Glenn, I'll second Devon's suggestions. Make sure there really is only > 14-14.5 volts at the lamp, and then check for vibration problems. > > Krokko > > -- > Dr. J. Christopher Krok > John Lucas Adaptive Wind Tunnel > Caltech MS 205-45, Pasadena, CA 91125 > > List sponsored by Dual Sport News at www.dualsportnews.com. List FAQ > courtesy of Chris Krok at: www.bigcee.com/klr650faq.html > Unsubscribe by sending a blank message to: > DSN_klr650-unsubscribe@yahoogroups.com . > > > > Your use of Yahoo! Groups is subject to > http://docs.yahoo.com/info/terms/ > > > >

[Chris Krok]

> Gentlemen - I know I'm using the word loosely-,

Arrrrrrrrrr!

> In the conditions/circumstances you describe why doesn't the fuse > blow before the bulb burns out ??

The stock fuse has about 5A of overhead, and the overvoltage required to blow the filament probably wouldn't be enough to overload the fuse. i.e., stock bulb is 60W (high) at 12 V (probably rated at 13.8-14, but i'm just ballparking it), so that's 5A. Assuming the filament resistance stays constant, we could raise the voltage to 24V and still be at the 10A limit of the fuse. (How much voltage does it take to fry a bulb, anyway?) Also, resistance of most materials decreases as they get hotter, so you might be able to put even more voltage across the bulb to get that 10A. Thinking about it more, if it really was a voltage problem, Glenn should be blowing everything on the bike, not just the headlight. Sounds more like vibration. Krokko -- Dr. J. Christopher Krok John Lucas Adaptive Wind Tunnel Caltech MS 205-45, Pasadena, CA 91125

[Judson D. Jones]

If the bulb draws around 5A in normal operation, it must ordinarily take a lot more than 10A to blow it. Otherwise a short would blow the bulb before the fuse, and we know the fuse usually blows without blowing the bulbs. In that case, why have fuses at all, as the bulbs would protect the circuit from overload.

--- In DSN_klr650@y..., Chris Krok wrote: > > > Gentlemen - I know I'm using the word loosely-, > > Arrrrrrrrrr! > > > In the conditions/circumstances you describe why doesn't the fuse > > blow before the bulb burns out ?? > > The stock fuse has about 5A of overhead, and the overvoltage required to > blow the filament probably wouldn't be enough to overload the fuse. > i.e., stock bulb is 60W (high) at 12 V (probably rated at 13.8-14, but > i'm just ballparking it), so that's 5A. Assuming the filament > resistance stays constant, we could raise the voltage to 24V and still > be at the 10A limit of the fuse. (How much voltage does it take to fry > a bulb, anyway?) Also, resistance of most materials decreases as they > get hotter, so you might be able to put even more voltage across the > bulb to get that 10A. > > Thinking about it more, if it really was a voltage problem, Glenn should > be blowing everything on the bike, not just the headlight. Sounds more > like vibration. > > Krokko > > -- > Dr. J. Christopher Krok > John Lucas Adaptive Wind Tunnel > Caltech MS 205-45, Pasadena, CA 91125

[Russell Dyck]

Or maybe it could be just a bad bulb. It does happen, doesn't it? - In DSN_klr650@y..., "Bogdan Swider" wrote:

> > Gentlemen - I know I'm using the word loosely-, > > In the conditions/circumstances you describe why doesn't the

fuse

> blow before the bulb burns out ?? > > Bogdan, who's trying add to his paltry electrical knowledge

by

> playing ask the rocket scientist and oil rig worker > > > > > If you have > > > a bad connection somewhere in the line, it will lower the

voltage

> > > hence drawing more amps and burning things up. We had a pretty > > > intensive inspection program on the drilling rigs that I used

to

> > > work on offshore. Checked all major circuit connections

monthly with

> > > heat seeker infared guns. It's amazing the damage a bad

connection

> > > will do. > > > > A bad connection creates a local spot of high resistance, which

lowers

> > the voltage at the load. The resistance also lowers the amount

of

> > current flowing through the circuit, and resistive heating will

occur at

> > the bad connection (wattage going to heat = I^2 * R). This is

what

> > causes melted connections, fires, etc. Since the heat output

goes up

> > with the square of current, it doesn't take much of a resistance

to

> > cause a problem. > > > > With typical resistive devices, the current draw goes down with

lower

> > voltages, rather than up. However, the case might be different

for

> > motors, and maybe that was an additional concern on the rigs. > > > > Glenn, I'll second Devon's suggestions. Make sure there really

is only

> > 14-14.5 volts at the lamp, and then check for vibration problems. > > > > Krokko > > > > -- > > Dr. J. Christopher Krok > > John Lucas Adaptive Wind Tunnel > > Caltech MS 205-45, Pasadena, CA 91125 > > > > List sponsored by Dual Sport News at www.dualsportnews.com. List

FAQ

> > courtesy of Chris Krok at: www.bigcee.com/klr650faq.html > > Unsubscribe by sending a blank message to: > > DSN_klr650-unsubscribe@y... . > > > > > > > > Your use of Yahoo! Groups is subject to > > http://docs.yahoo.com/info/terms/ > > > > > > > >

[David Kelly]

On Thu, Nov 14, 2002 at 01:23:22PM -0700, Bogdan Swider wrote:

> > Gentlemen - I know I'm using the word loosely-,

Burrrp! (excuse me!)

> In the conditions/circumstances you describe why doesn't the fuse > blow before the bulb burns out ??

What would you rather? The fuse blows and protects your headlight and now you are riding in the dark, or the headlight works until it can no more before burning out? This is much the same as the reason car headlights did not turn off automatically with the ignition. That it was deemed safer and more reliable NOT to route the headlight control thru unreliable ignition key switch. And more reliable to trust the driver to turn the lights off. The fuse should be close to the battery, not close to the headlight. The purpose of the fuse is to prevent a wiring fire. At work we often joke (only partially) that we put transistors in circuits to protect the fuses. The irony is many transistors are cheaper than fuses but the UL safety guys like to see fuses. So we put fuses in. -- David Kelly N4HHE, dkelly@... ===================================================================== The human mind ordinarily operates at only ten percent of its capacity -- the rest is overhead for the operating system.

[David Kelly]

On Thu, Nov 14, 2002 at 11:40:32PM -0000, Judson D. Jones wrote:

> If the bulb draws around 5A in normal operation, it must > ordinarily take a lot more than 10A to blow it. Otherwise a short > would blow the bulb before the fuse, and we know the fuse > usually blows without blowing the bulbs. In that case, why have > fuses at all, as the bulbs would protect the circuit from overload.

"we know the fuse usually blows without blowing the bulbs" ??? Do we really? I don't believe I have ever had a fuse blow on a motorcycle where I didn't short a wire while playing. In operation the only failures I have had were due to vibration. The fuses did not burn and "looked good" but when checked with a meter were found to be open. Once one knew it was there could eventually find the crack. My old Kawasaki H1 was bad about eating the main fuse that way. Good thing the fuse holder had a place for a spare. Not that the spare wasn't subject to the very same vibrations... The reason we have the fuse is because the fuse is located near the power source, the battery. If a wire rubs its insulation off and shorts to the frame then a bulb at the far end of the wiring harness is not going to prevent a fire. -- David Kelly N4HHE, dkelly@... ===================================================================== The human mind ordinarily operates at only ten percent of its capacity -- the rest is overhead for the operating system.

[Allan Patton]

----- Original Message ----- From: "Russell Dyck" > Or maybe it could be just a bad bulb. It does happen, doesn't it? > > Yes, it does happen, but they were cheap bulbs. About 15 years ago, on my VT1100, (also uses a H4). Lost high beam while riding Hwy. 50 east of Salida CO. Next day in Canon City at the Yamaha shop, I bought a new bulb. It was so cheap, I bought a spare also. They were made in Taiwan. First bulb was out after less than 100 miles. Second bulb was out at the next gas stop. On close inspection of the second cheap bulb with a magnifying glass, I could see a tiny hole where the quartz was sealed. I think the halogen gas leaked out and air got in. I went to a Honda shop and bought a more expensive Philips brand bulb. Made in Germany. It lasted for years. The spare H4 that I have now is supposed to be a "heavy duty" bulb that will stand up to vibration better. Allan A14

[dooden]

Ummmm maybe somebody got tired of the fuse blowing so they hardwired the fuse leads ?? or added a 20 amp or something. Just adding my... (umm it aint worth $.02) comment Dooden

--- In DSN_klr650@y..., "Bogdan Swider" wrote: > > Gentlemen - I know I'm using the word loosely-, > > In the conditions/circumstances you describe why doesn't the fuse > blow before the bulb burns out ?? > > Bogdan, who's trying add to his paltry electrical knowledge by > playing ask the rocket scientist and oil rig worker > > > > > If you have > > > a bad connection somewhere in the line, it will lower the voltage > > > hence drawing more amps and burning things up. We had a pretty > > > intensive inspection program on the drilling rigs that I used to > > > work on offshore. Checked all major circuit connections monthly with > > > heat seeker infared guns. It's amazing the damage a bad connection > > > will do. > > > > A bad connection creates a local spot of high resistance, which lowers > > the voltage at the load. The resistance also lowers the amount of > > current flowing through the circuit, and resistive heating will occur at > > the bad connection (wattage going to heat = I^2 * R). This is what > > causes melted connections, fires, etc. Since the heat output goes up > > with the square of current, it doesn't take much of a resistance to > > cause a problem. > > > > With typical resistive devices, the current draw goes down with lower > > voltages, rather than up. However, the case might be different for > > motors, and maybe that was an additional concern on the rigs. > > > > Glenn, I'll second Devon's suggestions. Make sure there really is only > > 14-14.5 volts at the lamp, and then check for vibration problems. > > > > Krokko > > > > -- > > Dr. J. Christopher Krok > > John Lucas Adaptive Wind Tunnel > > Caltech MS 205-45, Pasadena, CA 91125 > > > > List sponsored by Dual Sport News at www.dualsportnews.com. List FAQ > > courtesy of Chris Krok at: www.bigcee.com/klr650faq.html > > Unsubscribe by sending a blank message to: > > DSN_klr650-unsubscribe@y... . > > > > > > > > Your use of Yahoo! Groups is subject to > > http://docs.yahoo.com/info/terms/ > > > > > > > >

[corndawg389]

I recently had the exact same problem with my headlight.I replaced the bulb and it did the same thing.I ignored my better judgement and stopped at the bike shop and bought myself a new regulator/rectifier on the way home.That did no good.So I pulled the left side apart and found nothing wrong with the stator or wiring anywhere.Just then I stepped back and kicked myself hard in the butt for doing the same thing I always tell everyone not to do.When the butt swelling went down I looked at the bulbs a bit more clearly and found them to be fine.I had totally missed the fact that the connectors in the headlight plug were not fitting tightly onto the bulb causing(or because of)overheating and slight melting of the plastic plug.I squeezed each metal connector together gently then pushed them tightly back on and .... BAM! ...LIGHTS!!! If you're bulbs are actually burned out then this does you no good other than you (hopefully) got a good laugh at my dumbness.I guess what I'm saying is start at the bulb and work backwards from there. Also,while I've got the left side apart,I am doing the Doohickey upgrade.[I wonder when those things will be back from heat treat?] Scott A1 Jawa 361 RZ350 Honda C90