GL1100 (Standard) - Saving watts through LEDs (Chart)

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saganaga

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Was playing around the last few days with estimating how many watts would be saved via LEDs.

There's some rounding in the wattage, which means some of the numbers don't appear to add up. But let me know if you think there's a mistake.

Version 0.1

View attachment Electrical.pdf
 
Yeah, those numbers are fairly accurate... I don't see sums anywhere, but a couple notes to consider...

Some of these are constant loads, I see where you've identified 'normally on', but you might want to change this to an integer of percentage (like... duty cycle) to weight it for actual consumption. Headlamp, for instance, is constant. Brake light is intermittant load, the indicators are intermittant (we hope, particulary the Oil Pressure indicator)... the radiator fan can vary substantially based on riding conditions... and turn signals... well... depending on who you are, and how you drive, may get used predictably, or may not get used at all ;-D

And then there's battery charge rate...

The primary concern though, is that the consumption of power is a necessary thing, as the OEM alternator is a permanent-magnet stator system, controlled by a shunt-regulator. As the alternator spins, magnets induce potential on the windings, which is rectified, and sent out to loads... BUT...

When there's substantial current load, the stator's output voltage is limited by stator winding impedance (R and Z). Resistance being linear, if the stator resistance is high, then R ohms will determine what the limit of output current IS. Z is frequency-variable. if the impedance of the stator coils is high, it will generate plenty of voltage at the lower speeds, but will reach it's limit above a certain frequency, and then drop rapidly.

In the middle-range, any scenario resulting in excess power will yield higher-than-proper voltage, wherein the rectifier-regulator will 'shunt' off excess power through it's resistor grid. It's like a crowbar circuit.

that means, if you're spinning along at 3400rpm, and the system consumption is very low, battery fully charged, that alternator is still cranking out 250W, and you're only using 65, the rest HAS to go somewhere.

It's a clever design in some respects... but in others... not so much.

They selected the permanent magnet system because it eliminated brushes and spinning field. This is one of the most substantial design improvements that an external alternator provides- when they regulate, the field suppression of the regulator REMOVES excess load, rather than dumping it to waste. More crankshaft HP.

Now, what's really groovie about how Iriajimiri-San's design, is that he ran the alternator rotor in the OPPOSITE direction of crankshaft rotation... which means that when you blip the throttle, the engine speeds up, but it doesn't LEAN aggressively to one side (like a Guzzi)... because the torque force to spin it up, is counteracted by the force spinning up the alternator rotor.

Clever dudes... they were really clever dudes.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213289#p213289:33xx1aig said:
pidjones » Today, 4:21 am[/url]":33xx1aig]
Why do you think you need to save? Are you planning to add some loads like heated gear?

Curiosity's sake. I do upgrade every bike I have to LED taillights due to the brightness and the fact that I use a modulator

I do have a USB charger since I usually have my phone operating as a navigation unit on my bike. As well as a stereo, which, if you believe the marketing, is 4x50W output (although I only have two speakers and I don't believe the marketing). About the only additional feature I may add is one more USB charging port for a USB power bank (to recharge headsets at night while camping).

I will probably upgrade the headlight to LED for brightness reasons, which will net me a nice savings as well.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213330#p213330:2qm5pmkh said:
DaveKamp » Today, 6:32 am[/url]":2qm5pmkh]
Yeah, those numbers are fairly accurate... I don't see sums anywhere, but a couple notes to consider...

Some of these are constant loads, I see where you've identified 'normally on', but you might want to change this to an integer of percentage (like... duty cycle) to weight it for actual consumption. Headlamp, for instance, is constant. Brake light is intermittant load, the indicators are intermittant (we hope, particulary the Oil Pressure indicator)... the radiator fan can vary substantially based on riding conditions... and turn signals... well... depending on who you are, and how you drive, may get used predictably, or may not get used at all ;-D

For the normally on, I usually went with what was always lit. Tail light is normally on, but the brake light is off. Same 1157 bulb (well, two bulbs), but for the 1157 bulb, the low light filament is 8W, the bright light filament is 27W.

Unfortunately the LED replacement bulbs tends to give max wattage, instead of listing how much is used for the low light/bright light.

And then there's battery charge rate...

The primary concern though, is that the consumption of power is a necessary thing, as the OEM alternator is a permanent-magnet stator system, controlled by a shunt-regulator. As the alternator spins, magnets induce potential on the windings, which is rectified, and sent out to loads... BUT...

When there's substantial current load, the stator's output voltage is limited by stator winding impedance (R and Z). Resistance being linear, if the stator resistance is high, then R ohms will determine what the limit of output current IS. Z is frequency-variable. if the impedance of the stator coils is high, it will generate plenty of voltage at the lower speeds, but will reach it's limit above a certain frequency, and then drop rapidly.

In the middle-range, any scenario resulting in excess power will yield higher-than-proper voltage, wherein the rectifier-regulator will 'shunt' off excess power through it's resistor grid. It's like a crowbar circuit.

that means, if you're spinning along at 3400rpm, and the system consumption is very low, battery fully charged, that alternator is still cranking out 250W, and you're only using 65, the rest HAS to go somewhere.

It's a clever design in some respects... but in others... not so much.

They selected the permanent magnet system because it eliminated brushes and spinning field. This is one of the most substantial design improvements that an external alternator provides- when they regulate, the field suppression of the regulator REMOVES excess load, rather than dumping it to waste. More crankshaft HP.

I've seen a passing reference to upgrading the regulator a MOSFET unit, but I haven't delved into the advantages of that quite yet. Looks like the FH008EB (or equivalent) seems to be the unit used as a replacement.
 
Yep, I think your chart here is very thorough, and if not spot on accurate, certainly close enough. As for brightness, yes, the LEDs do a wonderful job of it, as the energy they consume is in a very narrow bandwidth at the design color, as opposed to an incandescent or halogen, which develops large amounts of UV and IR emmission useless to night vision (in normal humans, anyway).

The advantage to LEDs on a motorcycle or boat with permanent magnet alternator, is that there's more power available for auxiliary loads and battery charging. The bad part, is that no matter WHAT you do with your loads, a 500w permanent magnet alternator will ALWAYS be generating the greatest amount of output that it can, regardless of demand... no matter what, if your load is only 108 watts, you'll be generating the full 500w, it just means that the remaining 392w will have to be shunted off as heat.

That being the case, one of the first things a guy can do to increase his crankshaft horsepower is to find a way DECREASE his PM alternator's mechanical load.

The engineers had this figured out... as you spin that rotor faster, eventually, you get to a speed where the inductance of the stator's windings does NOT allow the magnetic field to change fast enough to 'keep up' with the phase angle of the rotor, and as a result, the mechanical load, and commensurate electrical output... drop off radically.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213356#p213356:1l1zss9p said:
DaveKamp » 52 minutes ago[/url]":1l1zss9p]
The advantage to LEDs on a motorcycle or boat with permanent magnet alternator, is that there's more power available for auxiliary loads and battery charging. The bad part, is that no matter WHAT you do with your loads, a 500w permanent magnet alternator will ALWAYS be generating the greatest amount of output that it can, regardless of demand... no matter what, if your load is only 108 watts, you'll be generating the full 500w, it just means that the remaining 392w will have to be shunted off as heat.

Here's what I don't understand.

For the sake of argument, say the stator isn't connected to anything (all the wires are clipped). Is it still consuming the power and just dissipating it as heat at the stator itself, or is there less of a drain on the engine?

Because if it's the later, than shouldn't a more modern regulator (MOSFET or similar) reduce the load on the engine?
 
[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=213358#p213358:2vwoahfs said:
saganaga » Thu Oct 03, 2019 6:19 am[/url]":2vwoahfs]
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213356#p213356:2vwoahfs said:
DaveKamp » 52 minutes ago[/url]":2vwoahfs]
The advantage to LEDs on a motorcycle or boat with permanent magnet alternator, is that there's more power available for auxiliary loads and battery charging. The bad part, is that no matter WHAT you do with your loads, a 500w permanent magnet alternator will ALWAYS be generating the greatest amount of output that it can, regardless of demand... no matter what, if your load is only 108 watts, you'll be generating the full 500w, it just means that the remaining 392w will have to be shunted off as heat.

Here's what I don't understand.

Because if it's the later, than shouldn't a more modern regulator (MOSFET or similar) reduce the load on the engine?
Yes :good:
 
Actually, no... because regardless of wether it's a bipolar transistor, or a MOSFET, or an IGBT, or a GTO, it's still switching ALL the excess to the shunt load.

Look at it like this:

You have a water pump... a piston pump with a rubber connecting rod. At slow speeds, the pump does a pretty good job of pushing water, and you have it pumping water up a pipe, into a reservoir that's WAY up in the air... like... 60 feet or so. The reservoir holds oh... 4 gallons or so.

From the bottom of the reservoir, you have an outlet going to lawn sprinklers on the ground... and most of them are running.

When the pump is turning really slow, the reservoir level slowly drops. When the pump speeds up, the reservoir level rises. IF you spin the pump fast, and turn off most of the lawn sprinklers, the reservoir eventually overflows... it will NEVER go higher than a certain point.

IF you try to spin the pump way too fast, the rubber connecting rod flexes, preventing the piston from moving much water.


This is about how your electrical system works. The permanent magnet rotor, spinning inside the stator, is a piston on a rubber connecting rod. As long as it goes slow, it will pump water, and the faster you go, the more it will pump, and the higher it can push it, until you reach a certain frequency, at which time, inductive and capacitive reactance of the stator coils reach cutoff frequency, at which point, the current and voltage drop off radically. It happens for much the same reason trying to spin a stock Ford 300 six at 13,000rpm results in... nothing.

The overflow of reservoir constitutes the 'limiting voltage' of the shunt regulator- it allows all excess to fall back to the ground.

Even when you're not using the power, the stator is being acted on by the rotor's magnetic field, and the excess goes to waste, which means there's a loss of crankshaft horsepower.

A racing engine would NOT have this type of system, because it inherently HAS to waste power to work properly. If it's not dumping through the shunt, it's because the rotor isn't spinning fast enough to generate high enough voltage to reach the regulation setpoint.

A racing engine would simply use a magneto, CDI or full-loss-battery ignition system... and of course, no lights or turn signals.
 
So in the poor boy conversion, it would then be a loss of engine power, since it's powering both the stock stator, as well as the alternator?

Or ???
 
If the stator's windings are fully open-circuit, and the insulation of the windings is intact and capable for the voltage induced (meaning, there's no shorted windings) then the load would be slightly greater than none. The slight load would be result of eddy currents inside the stator laminations.

Realize that in most poor-boy situations, guys are doing it because the stator failed, and they're not interested in going in after it. Ultimately, a good alternator conversion would include removing the old stator entirely, just leaving the rotor (because of it's aforementioned counter-torque/balancing).

An alternator, in contrast, has a direct-current excited magnetic field... and the regulator modulates the FIELD... when voltage is too high, the regulator reduces current to the field, thus magnetic intensity goes down. In effect, the regulated-field alternator uses crankshaft power in proportion to DEMAND on the output. It doesn't do it totally for free, as a little current is required to create that field, but the mechanical load difference is pretty small.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213380#p213380:3l6oi388 said:
DaveKamp » Today, 9:10 pm[/url]":3l6oi388]
If the stator's windings are fully open-circuit, and the insulation of the windings is intact and capable for the voltage induced (meaning, there's no shorted windings) then the load would be slightly greater than none. The slight load would be result of eddy currents inside the stator laminations.

If I'm understanding that correctly, shouldn't a mosfet-style regulator also reduce the load then, since it isn't regulating voltage by shunting current through a resistor to ground?
 
No, because it's not the MOSFET that's consuming the power- it's the shunt load.

Let's say you process apples, and they're delivered to you at a rate of 500 bushels of apples a day... but you can only use 100 bushels a day...

So at the end of the day, you take the extra apples, and throw them in the river.

After a while, you decide you need to be more efficient, so you make a chute from your bin to the river. When the bin has over 100 apples, the rest just roll down the ramp into the river.

The result is the same- 400 apples go into the river.

It doesn't matter wether the waste energy is disspiated in the shunt resistance, or the stator windings, or the transistor doing the switching- it's still being disspiated as waste heat... and the load is still being borne.

The problem with the permanent-magnet alternator, is that it cannot be 'shut down', and it's output cannot be externally modulated. It generates a set amount of power based on rotor speed and magnetic density, and coil winding impedance.

impedance (Z) is frequency dependant- it rises with speed (Z = XL + XC + R)... XL is inductive reactance, XC is capacitive reactance, and R is resistance. Reactance is NOT linear... so as rotor speed rises, it eventually hits a point where approaching resonance makes impedance skyrocket. This is the cutoff frequency of the coil... and above cutoff (Fco) output will drop radically, to almost nothing.

It is above FCO where the permanent magnet alternator's MECHANICAL load drops off. It doesn't go to zero, but it falls off dramatically. basically, you're spinning the field faster than the stator coils' windings and core can alternate... like a piston connected to a rubber-band connecting rod- the piston can't move fast enough, so the elastic rod absorbs it.
 
[url=https://classicgoldwings.com/forum/viewtopic.php?p=213377#p213377:3sha65qj said:
saganaga » Yesterday, 7:33 pm[/url]":3sha65qj]
So in the poor boy conversion, it would then be a loss of engine power, since it's powering both the stock stator, as well as the alternator??

The answer here is YES... and furthermore, if the stock stator's leads are open-circuit, but there's no regulator or shunt, they will generate substantial voltage as the engine passes through it's RPM band, it will eventually suffer degraded insulation which will break down, creating a shorted coil that will carry substantial current, develop substantial heat, and consume engine power in the process...

Which is the reason why it's best to remove the original stator...
 
Dave, I have to disagree with you as a Mofset regulator of the type that I recommend using is has a duty cycle (switchmode) to regulate the current required not by sinking the excess current to ground.
 
[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=213392#p213392:32b835gc said:
Ansimp » Today, 6:41 am[/url]":32b835gc]
Dave, I have to disagree with you as a Mofset regulator of the type that I recommend using is has a duty cycle (switchmode) to regulate the current required not by sinking the excess current to ground.


That's called a SERIES regulator, as opposed to a SHUNT mode regulator.

In a series mode regulator, the regulation dissipation occurs by allowing the stator winding voltage to go uncontrolled, and only meters off current and voltage as-needed, but uses dissipation of series resistance to limit voltage on the output.

When this is done, then yes, it does NOT need to sink excess energy to ground, but the side effect is that stator voltage goes very high, which puts stator winding resistance at risk. Series regulators are not uncommon to outboard motors, but adaptation of series regulators on outboards that were designed for sink, usually results in insulation failure. OEM series regulators on many outboards have water lines to them, or are mounted directly to a crankcase water jacket, to provide cooling.

Is there an aftermarket MOSFET switching series regulator available for the GL?
 
I’m in the belief that mixing the two is not healthy to stator at all ..good flow is how it gets rid of heat ...to me it’s flat out resistance and soon to be shorts that the only problem in the system ..and you can’t overload the output ...that’s like resistance in reverse
 
No, Joe... if the output of the stator is open circuit, they're will be no current flow, which means no power, and no dissipation. .. it means, however, that the voltage at those open wires will be very high. I haven't tested one of these, but I've worked on similar systems... my GN400 is battery less and uses a regulator I designed and built to replace the 6v system with 12v instead...

But this, and the cx500, and the hundreds of outboard motors ive worked on with pm stator setups frequently go 50 to 75, ac open circuit, and I've seen some that'd go in excess of 100vac.

With that kind of voltage available, it would not be unreasonable to use a common 80-277v switch mode power supply in place of the regulator, but the common ones I use won't work well because the input frequency range would not work... abs they drop out below 80v, when the pm stator will be cranking out 20v ...
 
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