Topic: Reg/rectifier question

[scottly]

I've done some putzing around town as well. Ever been through down-town Prescott, AZ? It's a very good test of low RPM charging and small battery capacity.

[TwoTired]

I do run into the charging problem fairly frequently when I go out with a riding club with the Honda and I am forced to cut through Sacramento rather than go on the freeway.

Is it because your headlight is deemed dim that you avoid the freeway?  750 or 550?

On the freeway your alternator should be capable of max loading.  What is your bike's loading?

Cheers,

[Spanner 1]

Waaay outside the design standards IMO..... Honda were  not eejits, allowed for slow speed 'showcasing' of their m/cycles with a nice big fat battery that could handle a goodly period of 'battery draining' operation at little above idle operation and no a  charging scenario... m/c design is not just performance at speed ya know ...

[scottly]

The Honda 750 charging system works better than some people think...

[Rgconner]

I do run into the charging problem fairly frequently when I go out with a riding club with the Honda and I am forced to cut through Sacramento rather than go on the freeway.

Is it because your headlight is deemed dim that you avoid the freeway?  750 or 550?

On the freeway your alternator should be capable of max loading.  What is your bike's loading?

Cheers,

Headlight is bright enough, PO put a h4 converter on it. Plenty of juice to drive it bright.

But... The XY interchange for interstate 5, 80 and 50 I would have to navigate is ugly, with poor line of site and not much room for error. Add to that all the work on the 50... It is more risk than I like to take in full darkness. The amount of trucking going through makes sure you will be dodging large sections of tire tread and other debris.

I grew up in Milpitas, and I can't think of an interchange that bad anywhere in the Bay area, not even 101/280/680, that is that poorly designed.

Maybe the crap around Emeryville after the Cypress structure collapsed in the quake of 89.

Better to tool through the surface streets, makes the wife happier. And I can stop and pick her up frozen yogurt. Makes up for a night out with the boys...

[Spanner 1]

My point is with a 'tiny' battery in your bike , you better not use it as intended 

[Rgconner]

Rg... if the alt. could never overcome the demand of the battery to be charged and the demand of the ign./headlight/ taillight/ turnsignals use... then the battery will deplete and the bike will stop dead..( fill in the miles)... as the alt. will be unable to keep the battery charged... seewhatimean ?

So, YES the charging does shut off when the regulator is told by the battery that it is fully charged, otherwise every SOHC bike would have a limited range or running before dead battery 
The stock regulator has 3 modes ; On 'full' power, On 1/2 power and Off.... that's it no other options.

Sorry, that is not what the manual says on pages 93 and 94 for the cb550. Open, full power. Closed, 10 ohm in circuit.

Even if the arm floated between the two contacts, it still has a path to produce power.

There is no off based on the schematics.

Manual is misprinted in that table frm those pages, so maybe that schematic is wrong too.

[TwoTired]

The stock Honda regulator has three states of control output.
-- The upper contact passes full battery or Black wire voltage to the alternator Field for full output capability (with enough RPM).
-- There is a no contact state, which inserts the 10 ohm resistor inline with the black wire input voltage.  This drops field coil current roughly in half.
-- Then there is the lower contact state, which grounds the field coil and allows no current to flow to the field coil.
The lower contact state occurs when the black wire represents an overcharge state of the battery, where it can be damaged, like over 15V.

Usually, when the bike's system is on the and the battery is charged, the Vreg cycles between the upper contact and the no contact state.

I know this description is slightly different than what the manual states.  But, the vreg diagram shows how it functions electrically.  The lower contact connects the F (Field) terminal to E (Earth) terminal.

Cheers,

[Spanner 1]

So, yes there is an 'off' state ( told by the battery )..... how long does it last ? How beneficial is it to cool the field/ stator coil and relax the battery from a charging state.... even if it's only minutes it's beneficial.. I think it's 10- 15 mins. before the alt. kicks back in.... anyone got proof otherwise ?

[TwoTired]

So, yes there is an 'off' state ( told by the battery )..... how long does it last ?

Not very long.

With the alternator turned off, the battery will lose voltage due to the system loads, ignition, lights, etc.  With the lights on, it's hard to imagine the alternator would be switched off more than momentary.

Perhaps after a long steady highway cruise with all lighting off, you could see more alternator off events.  But, it doesn't take much load on the battery to make it drop below 14.5V.  Natural full voltage on six wet cells is 12.6-8v.  Anything above that is a surcharge that must be maintained by an external power source.  Turn that off and the surcharge rapidly dissipates with almost any significant load.

Cheers,

[dawdish]

' Put the lights on and it's even worse'.... agrred, but onlt if ya putz around @ idle engine speeds....
Get over it, the stock lead/acid battery and energized field set-up is ideal for the low tech. batteries our bikes call for and optimises their life with the stock designed regulator... sorry can't beat it over electronics... period.... electronic regulators have one major flaw when installed in our SOHC's, they could care less about battery longevity.... good luck with 2 years due to 'boiling'  ... and several top-ups ...

I've been reading this thread with interest. May I break in with a thought... I have a Ballistic li/ion battery, and one of the characteristics of these batteries is that they stay at 12+ volts for long periods, then drop voltage abruptly to near 0 volts. Unlike lead acid, that drop voltage steadily on a "curve". It appears to me that the stock regulator can't deal with the abruptness of the li/ion, and perhaps a modern "ford" style regulator would do better, as there is no boiling of a li/ion battery. Just a thought, I may be wrong.

[crazypj]

So, yes there is an 'off' state ( told by the battery )..... how long does it last ? How beneficial is it to cool the field/ stator coil and relax the battery from a charging state.... even if it's only minutes it's beneficial.. I think it's 10- 15 mins. before the alt. kicks back in.... anyone got proof otherwise ?

 I already posted about original mechanical regulators, forget 15mins, or even 15 seconds, on/off occurs about 60 times a second which can and does lead to voltage spikes. (it's almost seventeen thousandths of a second )
You need a peak volt adapter for your multimeter to measure it though

[Spanner 1]

Crazypj..... all this time I thought the stock reg. had an 'off' mode.... I was wrong..... ( imagine that ! ).
The reg. 'relay' is biased towards the ' full voltage' mode and that mode is always selected until the battery reaches 14.5 v and the relay 'clicks' the arm down to the lower contact which allows minimal charging.
The field contact can't 'hover' between the 2 positions and produce a no charge state..... boohoo..... or can it  ... still don't know what you mean about 'switching 60 times a second '.... please explain .

[Spanner 1]

That's about the opposite of how it was explained to me RT by a very prominent member of this Forum.....
' the bike runs off the battery period, and the alt. serves only to replenish the battery as the battery demands it '....  yes, you will see a brighter headlight if the bike is running with the battery below full charge, but as the battery reaches full potential the alternator's output IS REDUCED TO A TRICKLE.... so the bike NEVER runs off the alternator exclusively.... what you are describing is a different type of system, may be common in the automotive world 
Another prominent member here made the crazy statement that ' once up and running the battery can be removed from the bike'   ... try that ! Just disconnect the battery Neg. while running at whatever rpm you think it will work and the bike will STOP instantly as you have TURNED_OFF the alternator....
And while I'm at it Rgconner, the regulator does have an 'OFF' setting... that is the contact pulled down by the relay ( battery has reached 14.5v )... the field ( white ) wire is now put to ground, so that 10ohm resistor you point-out has one end of it to ground = no charging, alt 'off'....... 

[Rgconner]

Spanner, it has already been pointed out that the description in the manual is incorrect.

THE MANUAL stated what happens is the 10ohm is put into circuit and the generation goes to .7A.

My only error is I Read The #$%*ing Manual, and you all say it is wrong.

[Spanner 1]

The 10 ohm resistor IS put into circuit, but only when the contact is 'hovering' between the upper and lower contacts... that is the mistake in the Manual... The diagram shows the correct operation which is 'no charging' when the lower contact is made ( battery @ 14.5v )... .... the real question is how long will the alt. remain off ??.....

[crazypj]

Mechanical regulator has points inside it.
The most basic way to explain it is this.
Its electromagnetic and points either open or closed
open= no volts to field coil
closed= battery volts to field coil
The maximum it can possibly cycle between open/closed is 60 time a second.
There are other modifications inside reg but personally I feel a fully electronic regulator is just more efficient

[Spanner 1]

Some misconceptions here  ... the stock reg. does not ' cycle' up to 60 hz........ where the heck did that idea come from ?? It does 'change' from one mode of charging to another over a period of  of time... might be in one mode ( say full charge, with a low battery ) for an HOUR while running down the road ! Normal. Then 'click' over to 1/2 charge for a period of time and then to 'off'......... then back to 1/2 charge, etc.  over at least several minutes......
 3 possible positions..... Closed = full charging  ( low battery )
                                    Center =  1/2 charging ( battery getting close to full charge )
                                    Closed =  no charging ( battery is full and full battery voltage causes the relay to pull the point to the grounded terminal ).... that's it .

[Spanner 1]

One question for ya RT.... with the bike running ( say the battery @ full charge, or whatever state of charge you want ), can you remove the battery as to allow the ( prove the ) alternator works like you 'think' it does to keep the bike running ?... Yes or no ?

[dawdish]

@spanner, this has been one of my problems...I am a master auto tech and own my own shop, so I have had difficulty understanding the SOHC charging system. Not only that but I have made the choice to use a li/ion battery, that creates its own problems... But I'm glad for people like you and TwoTired, and Dave500, that have helped me to understand the charging system.

[TwoTired]

One question for ya RT.... with the bike running ( say the battery @ full charge, or whatever state of charge you want ), can you remove the battery as to allow the ( prove the ) alternator works like you 'think' it does to keep the bike running ?... Yes or no ?

The answer is conditional.
The charging system delivers power to the POS battery cable.  The POS battery cable also distributes power to the key switch and the black wire distribution buss which powers the bike AND is what the vreg monitors and feeds to the alternator field coil to create a magnetic field.

Once the field is excited by the battery, and the alternator spins fast enough to provide all the power the bike requires in the way of load, part of what the alternator provides also keeps the alternator's magnetic field intact.  The battery can theoretically be removed at this point (definitely NOT at idle speed).  However, when the alternator output drops below a certain voltage and current level, the alternator's magnetic field weakens and the stator coil winding are drained of power before they can develop a decent peak sign wave.  And the engine, without the battery supplying buffer power stabilization, will stop.

The bike can run at all speeds without the alternator, and a charged battery of sufficient storage capacity.  It cannot run at all speeds without the battery.  Which is part of the reason why I like to say the bike runs on the battery rather than the alternator.  Further, without the battery smoothing the voltage surges, actual voltage regulation is of diminished quality. 

Because the alternator puts out AC, it must be converted to DC via a rectifier.  As the diodes turn on and off, spikes in the distribution line occur.  The battery provides a very low impedance to these spikes, to keep the magnitude of the spikes to a limited level within the diode withstand limits.  Without the battery, these spikes usually exceed the rectifier's absolute maximums, and failure can occur.  Further, if there are any other sensitive electrical devices attached to the black wire power distribution buss, transistors, diodes, and other active electronic devices can also be corrupted/damaged without the battery to quash those voltage and current spikes.
For this reason, as well as others, I do not recommend you run the SOHC4 without a battery connected.

Another forum member claims that once a LiFePO4 battery has reached full charge state or beyond, it no longer provides the low impedance the bike normally has with the lead acid battery.  I have not verified this claim.  But, if true, diodes and other electronic devices hanging off the power buss are in peril, should the battery ever actually reach a full or overcharged state.

Hope this helps,

Edit: Upon re-reading this, I noticed a couple of term errors regarding impedance condition and have corrected them.  It is low impedance that quashes voltage and current spikes rather than high impedance.  Sorry for the brain fart.
Consider this one rev B of the document.   

[scottly]

One question for ya RT.... with the bike running ( say the battery @ full charge, or whatever state of charge you want ), can you remove the battery as to allow the ( prove the ) alternator works like you 'think' it does to keep the bike running ?... Yes or no ?

The answer is conditional.
The charging system delivers power to the POS battery cable.  The POS battery cable also distributes power to the key switch and the black wire distribution buss which powers the bike AND is what the vreg monitors and feeds to the alternator field coil to create a magnetic field.

Once the field is excited by the battery, and the alternator spins fast enough to provide all the power the bike requires in the way of load, part of what the alternator provides also keeps the alternator's magnetic field intact.  The battery can theoretically be removed at this point (definitely NOT at idle speed).  However, when the alternator output drops below a certain voltage and current level, the alternators magnetic field weakens and the stator coil winding are drained of power before they can develop a decent peak sign wave.  And the engine, without the battery supplying buffer power stabilization, will stop.

The bike can run at all speeds without the alternator, and a charged battery of sufficient storage capacity.  It cannot run at all speeds without the battery.  Which is part of the reason why I like to say the bike runs on the battery rather than the alternator.  Further, without the battery smoothing the voltage surges, actual voltage regulation is of diminished quality. 

Because the alternator puts out AC, it must be converted to DC via a rectifier.  As the diodes turn on and off, spikes in the distribution line occur.  The Battery provides a very high impedance to these spikes, to keep the magnitude of the spikes to a limited level within the diode withstand limits.  Without the battery, these spikes usually exceed the rectifier's absolute maximums, and failure can occur.  Further, if there are any other sensitive electrical devices attached to the black wire power distribution buss, transistors, diodes, and other active electronic devices can also be corrupted/damaged without the battery to quash those voltage and current spikes.
For this reason, as well as others, I do not recommend you run the SOHC4 without a battery connected.

Another forum member claims that once a LiFePO4 battery has reached full charge state or beyond, it no longer provides the High impedance the bike normally has with the Lead acid battery.  I have not verified this claim.  But, if true, diodes and other electronic devices hanging off the power buss are in peril, should the battery ever actually reach a full or overcharged state.

Hope this helps,

Since it is obvious that I am the forum member you are both referring to, I feel I must respond:
1. Yes Ray, the motor will continue to run.
2. Lloyd, I said the opposite: the impedance of a fully charged LiFe battery is HIGHER than a lead acid battery, and thus provides less damping effect. Look at the graph you posted showing the charging characteristics. See the sharp rise in the voltage as the cell nears a full charge? This is similar to what I saw when bench testing my battery.

[crazypj]

Some misconceptions here  ... the stock reg. does not ' cycle' up to 60 hz........ where the heck did that idea come from ?? It does 'change' from one mode of charging to another over a period of  of time... might be in one mode ( say full charge, with a low battery ) for an HOUR while running down the road ! Normal. Then 'click' over to 1/2 charge for a period of time and then to 'off'......... then back to 1/2 charge, etc.  over at least several minutes......
 3 possible positions..... Closed = full charging  ( low battery )
                                    Center =  1/2 charging ( battery getting close to full charge )
                                    Closed =  no charging ( battery is full and full battery voltage causes the relay to pull the point to the grounded terminal ).... that's it .

That's a real nice description
 It's what should happen and does, most of the time
 When field coil gets full battery voltage (which will be over 10v or bike wont run) the magnetic field produced will cause a voltage spike and a max voltage around 17~18v @2,000 rpm.
Because voltage is above cut off point, regulator points open (Honda don't tell you any of this as their engineers/designers are totally infallible  )
 When you fit a smaller battery, you will get problems
Batteries still charge with AMPS and are regulated with volts
 BTW, 'that idea' came from Tony Tranter who has written a number of manuals on motorcycle electrical systems.
The original 1978 version gave a basic bio and a lot of different information compared to the latest (3rd) edition

[Spanner 1]

Sorry , bike won't run... let go of the throttle one time and the voltage produced will fall below the minimum level required to produce spark.... I mean can you ride the bike without a battery? = no. Can you re-start the bike if it stops = no, voltage cannot be produced even if you hook a pony motor to the back wheel and spin it at 5k rpm in gear   
And TT, what will happen to the regulator without the load of the battery across it ?.....and when the alt. produces more than 14.5v then it cuts out, bike dies. Without the 'extra' load of the battery the 14.5 volt cut-out point may be reached at some medium rpm..... what about all that ? Regulator can't behave as designed.

[TwoTired]

And TT, what will happen to the regulator without the load of the battery across it ?.....and when the alt. produces more than 14.5v then it cuts out, bike dies. Without the 'extra' load of the battery the 14.5 volt cut-out point may be reached at some medium rpm..... what about all that ? Regulator can't behave as designed.

The capacitive loading of the battery certainly helps smooth out the transients that the Vreg sees.  However, I'm pretty sure the Vreg can respond faster than the mag field can collapse.   The vreg switching frequency will be pretty fast, or at least faster than with a stabilizing battery attached.
 
I have swapped batteries in a cb550 while the engine was running (I don't recommend it, though), by removing one completely and then installing/connecting another one.  But, the lighting switch was off and I kept the engine revving @ 2200 rpm or so.  The engine will certainly die with a battery removed at idle speed.  The 5 ohm alternator coil of the 550 needs 31 watts to activate.  The spark coils needs about 24 watts.  That's 55 watts minimum loading that the alternator has to make to keep itself alive.  At idle it only makes 40-50Watts.  The 750 might make a bit more and its alt. field coils consumes about 5 watts less (24 watts).  I do remember that without the battery connected, the horn button became a kill switch and never made peep. 

Cheers,