Solid State Power Box for XS650

Well, I certainly didn't intend to get you upset. I will reduce my hypothetical scenario to 30 Amps. 20 from the battery and 10 from the PMA. In your answer, you continue to use a high voltage to show that the battery could not contribute to the total current in the event of a partial short, and of course I agree. What I have described is a partial short that would reduce the voltage to something less than the nominal battery voltage so that both the battery and the PMA would then supply the excess current caused by the short. Once the voltage goes below 14.5 Volts, the PMA regulator no longer does anything so the PMA is then free to deliver whatever its maximum current capability is to serve the demands of the short. Likewise, the battery would also contribute to the excess current demand from the short once the voltage has dropped below the nominal charge of the battery, typicall 12.6 Volts, so both the PMA and the battery would feed the excessive current demands of the short. The batteries contribution would decline as the charge diminishes, but in the time that the battery is providing current to the short it could blow the 20 Amp fuse, but the PMA would be supplying its maximum output of 10 Amps so the total current being fed to the short would be 30 Amps.

OK I agree if the load is such that the maximum the PMA can output is exceeded the PMA voltage will drop to at some point below 12.8 v and the battery at that point will supply current as well.

This is a very real situation that happens all the time if for example when using heated clothing. Using GS Suzuki numbers, you would typically have at 4K RPM and above 15 amps being provided by the PMA of about 20 amps available. About 11 amps go to light, ignition, headlamp (say 3A,3A,5A respectively ) with 4 amps charging current to the battery. We then have total PMA current 3A+3A+5A+4A=15 amps total but only 11 amps through the fuse box.

If you now add a load on it's own fused circuit as in the case of heated clothing if you now pull another 5 amps, then the PMA is providing it's maximum 20 amps and the 14.5 voltage will start to drop but still well above the 12.8V needed to discharge the battery.
So what really starts to happen as you approach this 20 amps is the battery voltage drops reducing the battery charging current. By the time you drop the voltage to 12.8V you now have the full 20 amps going through the fuse box. The currents are now 3A,3A,5A and 9A for lights, ignition, headlamp and accessory. There is nothing flowing through the main fuse as the battery terminals are at 12.8V.

So what happens as you add even more load? Well if it is heater load and you pull only one more amp you blow that fuse. If it is an ignition short you only get to pull 7 more amps before you blow that fuse. The battery fuse (i.e. the main) never blows.). So the worst case with a non standard heater load of 10 amps (just enough to avoid blowing the fuse) you can short out any other circuit and you can't pull more than 27 amps without blowing a circuit breaker(fuse). But that is the design; the wire powering the fuse box needs to be handle in worst case 40 amps if there are 4 10 amps circuits. realistically you should never pull that much and you should never pull that much from the battery. On a GS if you have a standard load (11 amps with no battery charging) and 4 amps of accessory you are at the limit for a 15 amp main fuse.

This is really the worst case for a 5 fuse fusebox and 10 amps of accessory load. The main fuse only saw 7 amps. The downstream fuses are fusing the individual circuits, and the main is there to protect the battery in case it is shorted not to protect a fused load.

If it were not for the 10 amp accessory load, you would still be at most 7 amps away from blowing any circuit but the current through the fusebox would not exceed 15+7=22 amps. I guess if your XS650 PMA can only generate 10 amps then you would pull current from the battery sooner but the loads are still the same and you are still a long way from blowing the main fuse. It really takes a shorting R/R to blow the main fuse.

This really draws to question the sanity of having a 20 amps main fuse for the battery. The bike only needs 11 amps to run if it is off the battery. I would need to have a 9 amp accessory load running off of a straight battery to blow the main. The GS standard main is only 15 amps.


Yes, I did introduce the issue of high voltage from both types of alternators due to a faulty regulator and, yes , I agree that has nothing to do with fusing. I was hoping that you could include some protection from high voltage in your design as that is a more common occurrence. In the case of the stock field excited regulators, you could provide a cutoff to the current to the regulator if it was controlled from your product as I think that you have voltage sensing capability and the regulator is powered from your product. Even if the faulty regulator was uncontrollable, you could cycle it on and off to maintain a suitable average voltage to the battery and provide an alarm to the rider.

I thought I told you I incorporated ISO 7637-2:2004 testing guidelines into the design. Much of the guidelines have to do with load dump. I'm taking a wild guess by this time you do not know what load dump is nor are you familiar with the standards. Down below you say even suggest they might not be relevant as they are auto standards and not motorcycle standards.

The PMA would be a bit more challenging. Using the same algorithm as the stock alternator, you could perhaps introduce a relay that is switched on and off in response to the high voltage sensed at the battery to maintain a good average battery voltage.

Isn't that a SERIES R/R you are describing?

An answer to these over voltage issues would be very useful, so I am dismayed that you "won't entertain this comment any further."

Without handing you a schematic and a BOM, I can only refer to the standards which I have now done 3 times. More than that I basically told you that there are shunting diodes incorporated. I'll tell you more ; there are 1500 watt zener snubbers on each low impedance line coming into/out of the SSPB. That is 6 1500 watt parts protecting against +/- 100V load dumps. Here is a part number. 1SMC20AT3

Basically the SSPB will protect anything attached to it from load dump from any source.
If it goes beyond the ISO test levels it has a sacrificial fuse to disconnect everything.

Also, I believe that there is a separate set of ISO electrical standards for motorcycles and mopeds so the use of automotive ISO standards may be inappropriate.

There is nothing here related to load dump. I guess you might also presume that load dump is not relevant to motorcycles.

http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_ics_browse.htm?ICS1=43&ICS2=140
 
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Waiting until the stock OEM alternator "gives trouble"..........................you may be waiting a long time. I've been using the stock alternator for over 8 years now, and it very reliably puts out 14.2 volts as I drive down the road. Once you remove the original stock rectifier and the stock mechanical regulator (1970 to 1979) , and replace them with new solid state rec/reg units, the charging system works extremely well.

It would seem, theoretically speaking, that a solid state field controlled alternator is much preferable to a PMA using SHUNT regulation, however many people move to the PMA with SHUNT regulators; Why is that? lack of current capacity in the old alternator?

I'm in the same camp as Grimly; if you have a PMA use a SERIES R/R.
 
I'm not electrically minded but can grasp very rudimentary systems.

I have been reading, (not thoroughly i do have the lawns to mow), and to me when a simplification of a system has created this much explanation, or also seems to be some lack of knowledge about the XS650, my inclination is to forget about this system because i would feel i am being confused/bamboozeld with to much technical information that isn't required for a sales pitch.

Feeling comfortable with a seller is as important as the product.

Don't bother to dissect my post and comment on each dissection please, take it for what it is
 
I'm not electrically minded but can grasp very rudimentary systems.

I have been reading, (not thoroughly i do have the lawns to mow), and to me when a simplification of a system has created this much explanation, or also seems to be some lack of knowledge about the XS650, my inclination is to forget about this system because i would feel i am being confused/bamboozeld with to much technical information that isn't required for a sales pitch.

Feeling comfortable with a seller is as important as the product.

Don't bother to dissect my post and comment on each dissection please, take it for what it is

For those that care, the discussion is to explain to pamcopete why the OEM wiring of the XS650 (battery/alternator/fusebox) is the right way to wire it regardless if there is a field controlled alternator or a PMA.
 
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"For those that care"..............I guess your referring to me, as you did quote my post...........

If you don't know why people are converting to PMA's, do some research on the matter, (don't take my word for it), and you'll find the Stator/rotor system on the XS is reliable and sufficient for its needs. It is lack of maintenance, (that is the cause of the popular misconception that is advocated and advanced by sellers of the PMA's), that causes the system to overload and fail.

lack of maintenance, is the black box going to solve that problem.

And yes, i see it has taken 2 page of dissection about how the value of 35amps was got, and the placement of a fuse.
 
I think I referred to your post but obviously did not address you. I did not mistake you for someone that gives a$hT :)
 
posplayr,

"I incorporated ISO 7637-2:2004 testing guidelines into the design"

ISO 7637-2:2004 has been superseded by ISO 7637-2:2011 .
 
Waiting until the stock OEM alternator "gives trouble"..........................you may be waiting a long time. I've been using the stock alternator for over 8 years now, and it very reliably puts out 14.2 volts as I drive down the road. Once you remove the original stock rectifier and the stock mechanical regulator (1970 to 1979) , and replace them with new solid state rec/reg units, the charging system works extremely well.

Well, that's good to know, and I look forward to saving some coin on that. I bought in a Jeep regulator and 3ph bridge diode in case the Brand-X reg/rec gives up on the job.
Once all the lights are LEDs the stock alternator will be quite happy powering the load, I hope. Since this is essentially a summer bike, there will be no heated grips, seat or built-in cosy washstands, shavers, or other power-hungry accessories. :)
 
It would seem, theoretically speaking, that a solid state field controlled alternator is much preferable to a PMA using SHUNT regulation, however many people move to the PMA with SHUNT regulators; Why is that? lack of current capacity in the old alternator?

I'm in the same camp as Grimly; if you have a PMA use a SERIES R/R.

According to the Haynes Book of Lies, the output is 11A @ 2000rpm, iirc. Whether that's true is a great unknown, but it doesn't look all that good. Otoh, as I mentioned, with LEDs all over, there is now adequate capacity and the need for the abysmal 40W sealed beam simply goes away. I wondered why mine had that - I thought the PO had just cheaped out and bought one from a car store to save money - no, it seems it's necessary.
Thank gawd for progress. I'd hate to be going down a back road at night, relying on that.
There are some of you who will recall the dreadful sealed beams that were fitted on many cars of the 60s - that there were two of them was their only saving grace. One 40W would be awful.
 
According to the Haynes Book of Lies, the output is 11A @ 2000rpm, iirc. Whether that's true is a great unknown, but it doesn't look all that good. Otoh, as I mentioned, with LEDs all over, there is now adequate capacity and the need for the abysmal 40W sealed beam simply goes away. I wondered why mine had that - I thought the PO had just cheaped out and bought one from a car store to save money - no, it seems it's necessary.
Thank gawd for progress. I'd hate to be going down a back road at night, relying on that.
There are some of you who will recall the dreadful sealed beams that were fitted on many cars of the 60s - that there were two of them was their only saving grace. One 40W would be awful.

At 11A unless there were some smaller lighting loads (e.g. headlamp), the battery is going to get shortchanged and never really charge. With LED's all around the field controlled alternator is probably just fine assuming a solid state reg and maintenance is kept up on it.
 
From the 1970 XS1 manual. Charging output = 100 watts @ 2000 rpm.
1970XS1-Charging.jpg

The rating slowly increased over the years. How, I haven't a clue...
 
From the 1970 XS1 manual. Charging output = 100 watts @ 2000 rpm.
View attachment 54850

The rating slowly increased over the years. How, I haven't a clue...

Squeezed in a few extra windings and upped the field strength a bit, iwt. In automotive terms it's a fairly short alternator for the day and its output is probably about right for its size, if the designers were being a bit conservative. I think they succeeded if their desire was reliability, but it comes at the cost of decent output on the front light.
No matter; if I fit the bike with modern lighting and keep the strain off the alternator, it will probably be fine.
Two things occur to me; I had the loan of a 1979 Special when it was new and I did some night riding with it. It wasn't too bad, but wasn't great, either. I do recall it was nothing like as good as a halogen H4, but many bikes of the 70s had lights that weren't all that. At the time I was unaware of it having such a low powered light, but the charging system and connections being new, things were working just as well as they could back then.
The other thing is that a low-powered light is ok on a dark road with no other traffic - when you have a mix of patchy street lighting and oncoming traffic, the feeble candle glow of crappy lighting really shows its shortcomings as your eyes have to adjust rapidly from the dazzle to the gloom, and age takes its toll, in this, as with so many other things.
Me? I'm getting older and I want as much light as possible :D
 
Squeezed in a few extra windings and upped the field strength a bit, iwt. In automotive terms it's a fairly short alternator for the day and its output is probably about right for its size, if the designers were being a bit conservative. I think they succeeded if their desire was reliability, but it comes at the cost of decent output on the front light.
No matter; if I fit the bike with modern lighting and keep the strain off the alternator, it will probably be fine.
Two things occur to me; I had the loan of a 1979 Special when it was new and I did some night riding with it. It wasn't too bad, but wasn't great, either. I do recall it was nothing like as good as a halogen H4, but many bikes of the 70s had lights that weren't all that. At the time I was unaware of it having such a low powered light, but the charging system and connections being new, things were working just as well as they could back then.
The other thing is that a low-powered light is ok on a dark road with no other traffic - when you have a mix of patchy street lighting and oncoming traffic, the feeble candle glow of crappy lighting really shows its shortcomings as your eyes have to adjust rapidly from the dazzle to the gloom, and age takes its toll, in this, as with so many other things.
Me? I'm getting older and I want as much light as possible :D



The 40W rated Cyclops 3800 only pulls 2.2Amps@14.5V on High beam , so figure a 20W LED headlamp is about 1/2/ The biggest LED 1156 bulbs I have found are 0.5Amps@14.5 (40 5050 emitters) but the 27 5050 and 18 505 are about 330 mA/280 mAmp respectively and are close to the same. In summary, with LED lighting you would need between 2-4 amps total for all lamps (headlamp and signal) and with a 3 amp coil draw you would still have 4 amps available for charging a 14Ahr battery.

If I had one, I would be very tempted to just stick with the stock field control alternator with solid state reg and forgo an aftermarket PMA.
 
According to the Haynes Book of Lies, the output is 11A @ 2000rpm, iirc. Whether that's true is a great unknown, but it doesn't look all that good. Otoh, as I mentioned, with LEDs all over, there is now adequate capacity and the need for the abysmal 40W sealed beam simply goes away. I wondered why mine had that - I thought the PO had just cheaped out and bought one from a car store to save money - no, it seems it's necessary.
Thank gawd for progress. I'd hate to be going down a back road at night, relying on that.
There are some of you who will recall the dreadful sealed beams that were fitted on many cars of the 60s - that there were two of them was their only saving grace. One 40W would be awful.

If you're referring to the old stock type 40 watt headlights, yes they were poor lighting. I replaced the stock type with a 40 watt Halogen, and find that it gives a very good light.

I recommend you use an LED taillight/licence plate light, if you have not done that already.

11 amps at 2000 rpm is about right for the stock alternator, but since no one runs their engine at 2000 rpm when driving down the road (for any length of time), its rather meaningless.

Most people will drive most of the time at approximately 3500 to 4000 rpm (just an example). Lets pick 3800 rpm and the stock alternator can put out about 13.9 amps.

Current consuming loads @ 3800 rpm:
Alternator rotor 1.4 amps
Pamco ignition 60 degreee dwell 0.7 amps
LED taillight/licence plate light 0.073 amps
55 watt headlight +meter lights 4.6 amps
current availble to charge battery 2.0 amps

Total loads 8.77 amps

which leaves a spare capacity of 5.1 amps (@ 3800 rpm)

So you can see that the stock alternator has no problem at all to supply the loads and charge the battery, while driving down the road.

OK so now you are stopped at a traffic light, engine is at 1200 rpm, and alternator is only capable of generating 8 to 9 amps. Also the alt rotor now draws 2.6 amps via the regulator, making the total load 9.97 amps. That shows that the battery will be short changed at 1200 rpm, in other words likely no charging at idle, and in fact the battery may be discharging a small amout of current.

When idling at 1200 rpm, my voltmeter usually shows around 13 to 13.5 volts, which means the battery is neither being charged nor is it being discharged. Only the alternator is supplying the current for the bikes loads.

Now if your turn signals are selected (engine still at 1200 rpm), those wattage hungry 1157 bulbs will draw another 4.2 amps. The battery is called upon to supply the extra current since the alternator has run out of electrons. The volt meter shows the voltage bouncing down to 12 volts in sync with the flasher relay.

So does the stock alternator do a good job......................yes it does. Does it charge the battery at 1200 rpm...............no it does not, but there is no need to, as the battery is charged up as you drive along the road.

I always use the starter motor, and my engine has never failed to start over the last 8 years.
 
The coil draw is an average based on the dwell angle, or conversely the duty cycle. A typical 2.5 Ohm coils will draw 14.5 / 2.5 = 5.8 Amps when it is on. With a 60 degree dwell angle, the current draw averages 60/360 = 0.16 X 5.8 Amps = .9 Amps X 2 = 1.8 Amps average. A 4 Ohm coil would draw 3.6 Amps when on so with a 60 degree dwell angle the average would be .16 X 3.6 = 0.58 Amps X 2 = 1.15 Amps. A set of points with a 4 Ohm coil and a 90 degree dwell would draw about the same a the 60 degree 2.5 Ohm coil. The actual draw would be slightly lower with the 60 degree electronic ignition because the driver transistor drops about a Volt.

If you lose your charging system far from home, you can disconnect the headlight and the regulator and ride for about 5 hours if you catch the failure soon enough while the battery is still close to being fully charged. The trick is to catch the failure sooner rather than later. There is a very simple circuit available to warn you if the alternator has failed that illuminates the white headlight lamp for those bikes so equipped. For the later models, just shut down the engine and restart and the headlight will not come on to give you that extra 5 hours to get back home if you also disconnect the regulator.

whitelight.jpg

whitelight2.jpg


I think that any sophisticated power management system should incorporate a warning for a failed alternator to provide the rider with an opportunity to either return to base or ride to a safe harbor while he still has some battery power. There should also be a load shedding feature to prolong the available battery power to do so and that the headlight should either be turned off or dimmed and that the voltage regulator, which is no longer needed with a failed alternator, should be disconnected to save battery power. Being able to limp home with a failed alternator is important.

cockpit3.jpg
 
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The coil draw is an average based on the dwell angle, or conversely the duty cycle. A typical 2.5 Ohm coils will draw 14.5 / 2.5 = 5.8 Amps when it is on. With a 60 degree dwell angle, the current draw averages 60/360 = 0.16 X 5.8 Amps = .9 Amps X 2 = 1.8 Amps average. A 4 Ohm coil would draw 3.6 Amps when on so with a 60 degree dwell angle the average would be .16 X 3.6 = 0.58 Amps X 2 = 1.15 Amps. A set of points with a 4 Ohm coil and a 90 degree dwell would draw about the same a the 60 degree 2.5 Ohm coil. The actual draw would be slightly lower with the 60 degree electronic ignition because the driver transistor drops about a Volt.

If you lose your charging system far from home, you can disconnect the headlight and the regulator and ride for about 5 hours if you catch the failure soon enough while the battery is still close to being fully charged. The trick is to catch the failure sooner rather than later. There is a very simple circuit available to warn you if the alternator has failed that illuminates the white headlight lamp for those bikes so equipped. For the later models, just shut down the engine and restart and the headlight will not come on to give you that extra 5 hours to get back home if you also disconnect the regulator.

whitelight.jpg

whitelight2.jpg


I think that any sophisticated power management system should incorporate a warning for a failed alternator to provide the rider with an opportunity to either return to base or ride to a safe harbor while he still has some battery power. There should also be a load shedding feature to prolong the available battery power to do so and that the headlight should either be turned off or dimmed and that the voltage regulator, which is no longer needed with a failed alternator, should be disconnected to save battery power. Being able to limp home with a failed alternator is important.

cockpit3.jpg

People normally use a voltmeter to tell when the charging system is dying.

These are small waterproof meters that are very accurate for $5. They are also earthquake proof (see the add).

http://www.ebay.com/itm/30161167022...49&var=600491904478&ssPageName=STRK:MEBIDX:IT

These are not waterproof but are small enough to be integrated into a gauge. They also has a trim pot on the back for small voltage corrections. Cost is $1.5 USD

http://www.ebay.com/itm/380687977328?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

I see in your picture you have the same.

As far as load shedding, unless you are talking about off road use, in the US it would be illegal to ride for 5 hrs without lights. Going to LED lights on low beam it would be easy to get by on 1.5 Amps. At that point, you would be better to load shed the ignition and install a relay to put a ballast resistor in series with the coils to reduce power consumption. It would be easy enough to put a relay in series with the field winding to disable that , or just unplug it.

You can also carry a larger battery if cost is not a consideration. The new batteries will easily double your battery capacity over lead acid.
 
This is a plot from a clamp on current probe measuring the current draw for an GS electronic ignition and a pair of 3.0 Ohm Accel yellow coils. They measured at 3.3 ohms cold. This is a 4 cylinder wasted spark engine so it is firing 2 times per revolution. The same as a 2 Cylinder.

The scale is 1 amp per division starting at the small arrow marked with a 1. The average current is 2.47 amps with a peak at 3.1 amps. Data taken at 2500 RPM.

3.0%20Ohm%20Accel%20Coils%202500%20RPM_zpstvknfuaz.jpg
 
posplayr,

Well, I'm a little surprised at some of these answers considering that you are promoting an electrical control and monitor system.

1. Yes, I have a voltmeter. Your product is supposed to take care of electrical load management, with or without a voltmeter.
2. Yes, it is illegal to ride in the US without a headlight. That is why I suggested that a electrical management system could dim the headlight to remain legal, or risk the ticket and ride home.
3. If you inserted a ballast resistor in the ignition system the ignition system would fail at about the same time due to lower current in the primary.
4. Carrying a larger battery is not a viable option due to mounting constraints.
5. A larger battery would require a larger capacity alternator.
6. You would still need an early warning system to take advantage of the larger battery capacity. Not having that simply means that you would be able to ride even further away from home before you realize you have a problem.

What is needed is a sophisticated electrical control and monitoring system to configure the electrical system to obtain the maximum time to ride home or to a safe harbor in the event of an alternator failure. You can configure your product any way you want if it accomplishes that important objective.
 
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