| Author | Message | ||
     Hootowl |
Is that a 260 model Simpson? | ||
| Bomber |
Hoot to be honest, I don't remember . . . .it's sittin up on a shelf in the Entropy Lab (a.k.a., my garage) for exactly the cool factor you mentioned . . . .it's right next to my tach/dwell meter, and a slightly newer analog meter, whose manufacturer I don't remember right now, and next to my dead monkee in a jar. that shelf contains a number of treasures | ||
| Road_Thing |
"Entropy Lab" -- Boy ain't that the truth! "tach/dwell meter" -- do you still have a points file? (I do...) r-t | ||
| Bomber |
of course . .. .how else would I maintain the '31 ford? or the old parallel twin flat tracker or my pacemaker (sheesh . . . the silly questions some people ask) | ||
| Mrossi |
Thanks Henrick, I was the voltage regulator after all M. Rossi | ||
| Bomber |
Hoot . . .. . .260 Simpson, aye (was in the entropy lab last night and remembered to look | ||
| 99x1 |
About a month ago, my Yuasa battery seemed weak, and wouldn't turn the starter over when cold - boost started OK. Had battery tested, showed virtually no CCA (cold cranking amps). Replaced battery, and all seemed fine. About a week ago, again wouldn't start when cold - Had battery tested, original 220 CCA was now 60. Checked charge voltage - 14.8 at idle going up to >17 volts at 4000 rpm (a little embarrassing, as I am an Electronics Technologist..). AFAIK, the worse thing that can be done to a sealed battery is to overcharge it - no recovery is possible. Checked regulator diodes with meter - diodes seemed OK. Regulator is potted with a soft compound, so I removed it (~2 hrs). Found 1 SCR had a loose connection on the gate (thermal cycling - solder cracks around lead). Took out 2 Torx screws on rectifier and another 2 Torx screws on regulator section. Replaced both SCRs, re-potted with Loctite ColdWeld and tested on bike - works great. I think what happened is one of the SCRs was not turning on (see diagram below) and allowing voltage to go high. Moral of the story: Check your charging voltage... John  | ||
| Buelliedan |
Hey 99X1, I have absolutely no clue what AFAIK is and you completely lost me once you took apart the regulator  | ||
| Josh_ |
well As Far As I Know most people just replace those little black boxes when they misbehave. Cool, someone ought to show this guy the speedo sensor issue. | ||
| Bluzm2 |
99X1, Nice work on the reverse engineering of the VR. Question though, what sets the OVT level? In your schematic above, is there some passive components left out for clairity? Great job BTW, I'd have probably chucked it and replaced the bugger. Even though I've got the know how, there is that pesky time thing.. I never have enough to take the time to do cool stuff like that. Brad | ||
| Sickquad |
I hate my voltage regulator. | ||
| Reepicheep |
The design for that schematic makes no sense sense to me. When the battery is over voltage, it simply shorts out the stator. It would work to protect the battery, but just sinks a bunch of power through a short circuit. Seems like that would rob horsepower, wear out the stator, and burn up wires. Is there a mechanical reason there must be a constant (heavy) current load on the stator? How'd you get the potting compound out? Acetone or something? Thanks for the info! | ||
| Aaron |
It's a shunt regulator ... you can buy series regulators on the aftermarket. But, so far I haven't been able to find it on the dyno. Even completely disconnecting the stator I can't find anything. | ||
| Reepicheep |
I am getting some dim recollection of going over this before. Even one horsepower creates a LOT of electricity, so I guess even shunted it would take less then a horse or two. I know Aaron knows this stuff even better then I do, but for others following that don't know the conversion offhand, one horsepower is around 746 watts, which corresponds to 62 amps on our 12 volt systems, which is probably the most a normally running bike would ever consume. Even if it was 122 amps, 2 horses would be hard to spot on the dyno. | ||
| 99x1 |
"Question though, what sets the OVT level? In your schematic above, is there some passive components left out for clairity?" Yes, the passive components for OVT where left out - a couple of zeners, and some diodes /resistors. The potting compound is a soft rubber and "kinda" peels out. The SCRs (2N6507) are $1.08 ea. (Digikey). "The design for that schematic makes no sense sense to me. When the battery is over voltage, it simply shorts out the stator." Yup, that's the way it works - if your headlamp burns out (for example) - the regulator has to shunt that power and will run hotter. It's kind of a simple, no nonsense design - and is used on lots of other bikes (e.g. Honda VFR). Series regulators cause high voltages and since the normal failure for an SCR is shorting - the shunt style is kind of fail-safe (most times). John | ||
| Al_lighton |
So I'm driving to work today and my tach starts jumping up and down by about 1000RPM. The bike is running ever so slightly rough, like an occasional misfire. It gets me to work, I figure I'dd fiddle with turning it off and on. The bike dies as soon as I touch the ignition switch. Had a fun ride home from work. I figured out it runs good and the tach doesn't jump if I hold the switch just so (S1W, on side of bike). Nice riding one handed while lane splitting Socal Traffic. Get home, yank switch, see this: Left one is a good one I bought used a while ago from BHR, right one is the stocker on the bike.  It looks like the crimp job on the wires is defective. My S3 has been a bit funny with the switch of late too..I wonder if I'll find the same thing on it. I'm going to fully pott the back of the BHR switch before mounting it, like HD should have done when the made the damned thing. One would think Harley would have that part down by now. | ||
| Grunt |
Hey guys, i got a question for ya. i have recently become a proud owner of a 03 firebolt :-D . any how, i don't care to much for the bug eyed turn signals, has anyone used the low pros? and how did they turn out? any pics? i found some clear tear drop style ones that i like, but am curious to see a pic before i start cuttin wires. Bill | ||
| Jmartz |
Electrical Question... I have read that if you were to put a switch on the headlight and operate the bike in that fashion (not that you actually could since it is a crime to do so in most states) the battery would be cooked by excess charge. Apparently the system is designed to send the right amount taking in consideration other loads. If a "series" regulator was installed would the amount going to the battery then be right under modified load conditions? | ||
| Ccryder |
Just in case anybody is interested in some bright LED Brake/ License plate lights take a look here: LEDtronics They have red LED's for brake and white LED's for license plate for a total of 24 LEDs. I have a set on the way for Passion Time2Work Neil S. (Message edited by ccryder on May 09, 2003) | ||
| Blake |
JM, Interesting question. Without the current draw of a headlight, will the battery be subjected to overcharging? I don't know. If the over voltage protection in the charging circuit is robust and fine enough, it shouldn't. But who knows. Interesting question. Hopefully someone who actually knows the answer will share it with us. | ||
| Blake |
It also just struck me that I recently needed to replace the battery in my Cyclone. Though it was around three years old or more, it had also been subjected to numerous track days sans headlight just prior to pooping out. Maybe racers remove the charging system as much to save their battery as to reduce weight. The old Harleys allowed running without headlights. If the charging system for an early 80's Harley is not different than that for today's Buell that would suggest that absence of headlight current draw would not be a problem. I'm betting it is not a problem... mainly because I don't want to have to worry about it on the race track. ![:]](http://www.badweatherbikers.com/buell/clipart/proud.gif) | ||
| 99x1 |
"Apparently the system is designed to send the right amount taking in consideration other loads. If a "series" regulator was installed would the amount going to the battery then be right under modified load conditions?" The regulator shorts the stator to keep the voltage down - if you disconnect the headlight, the power (55 watts) will then be dissipated by the regulator. It should be able to take it, the parts inside seem to be rated high enough (2N6507 SCRs are rated at 25 amps each). The load through the rectifier portion is reduced though, so less heating will occur in the diodes. (see circuit diagram in previous post). A series regulator works by opening up the path from the stator - this leads to very high voltages being generated (>100 volts with no load) and is harder to design to prevent spiking. With either type of regulator, the battery charging will be regulated, regardless of load... John | ||
| Ocbueller |
Hmmm, "spiking" as in spiking the speedo sensor to death? SteveH | ||
| Reepicheep |
Hmmm indeed. If that schematic above is correct (and no reason to believe it is not), 55 watts additional watts dissapated by the SCR would mean 91 amps (assuming the forward voltage drop through an SCR is .6 volts, which is what I recall, and that there is zero voltage drop through the wires, which is not likely). Now the SCR's have a 50% duty cycle, alternating SCR's take the full load and switch rapidly back and forth, so that could probably be normalized down to effectively 45 amps. Adding in what is probably another volt or so dropped through the wiring, and you still have 34 amps or so peak through the SCR. The 50% duty cycle then puts you back around an effective 17 amps. Which is fine in theory, but is awfully close to the limit for those SCR's. Maybe racers ought to disconnect the headlight lead, and reconnect it to some sort of cooling fan. It will keep the regulator from heating up, at the same time it helps move air across the engine when the bike slows for any reason. Instead of a series or a shunt regulator, it would be possible to build a switching regulator. No high voltages, no excessive heat, no wasted engine power. Which brings me to a tangent. Is there a readily available switching regulator part, like the switcher equivalent of the LM317, that can be adjusted for different voltages? Seems like a pretty obvious chip to build. I made a couple of half hearted searches for one, and never found one. Now I understand why that regulator has such a big honkin heat sink.... | ||
| 99x1 |
AFAIK, the SCRs wouldn't see an "excessive" load - the regulator would run hotter though. The SCR would turn on near the top of the sine, so it wouldn't see 50% RMS. As well, once the stator is shorted, a lot of the power will be dissipated in the resistance of the stator itself. The SCR also has (probably) ~75% of the cycle to cool. I think if it is working OK, it should handle anything you could do to it (no load, full load, etc...). As with auto alternators - the worse thing that can happen to a charging system is for the battery to "unload". If a battery connection comes loose, the charging system will spike as it sees full-load -> no-load -> full-load : this could possibly take out speedo sensors. (Speedo sensors have a microprocessor in them for waveshaping to digital). I think we are probably getting too technical here..... John | ||
| Blake |
I think we were originally wondering if the lack of a headlight would hurt the battery due to overcharging. The answer is no? Good grief, ask one little electrical question and the EE professors come out of the woodwork.  | ||
| 99x1 |
"...lack of a headlight would hurt the battery due to overcharging. The answer is no?" IMHO, Correct. "Good grief, ask one little electrical question and the EE professors come out of the woodwork." Let the one without (mechanical) sin cast the first stone.  | ||
| Reepicheep |
X1.. I did not think about the point in the cycle where the SCR would trigger, that is probably what brings it back in a comfortable range for the rating of the SCR's. Good observation about the stator power dissipation as well, as that thing sits in an oil bath, it will dump heat pretty well, and it's construction would not be very heat sensitive in the first place. I agree with X1, no headlight won't hurt the battery. The first thing to break would be the regulator, and that could probably get hot enough to boil water before things start failing. | ||
| Rick_a |
Loads exceeding the original design will harm the charging system...too little is always a good thing. I thought that aside from some heat losses due to the small amount of resistance that no energy is "dissipated" in a charging system. When the stator is shunted to ground, the induced current simply runs a loop back to the stator without being converted to DC, isn't it? There is no energy being used and it obviously can't be destroyed so why would the stator run hotter? | ||
| 99x1 |
"Loads exceeding the original design will harm the charging system.." No, the battery will supply the excess and just not be charged. "that no energy is "dissipated" in a charging system." This is true for a "typical" charging system, but because of the fixed permanent magnet field - there is no control of the magnetic field (as there is on the rotor of an auto alternator). The output of the stator is shorted to apply more load to keep the voltage at the correct level through the rpm range. At idle (<2000 rpm) the output is less then 14 volts (with normal loads) so no shunting of power is done. Increasing the load, decreases the voltage (due to stator and rectifier drops) - so the regulator dissipates less power. "...too little is always a good thing" Except for money, sex, permanent magnet alternators.... |
