Voltage fluctuation due to temperature?

[FrankPa]

So, here's the deal...

I added the digital voltmeter to the left side guague location like a lot of us have done. During the summer, fully charged after 30 minutes or so of riding, the voltage reads 13.7 volts.

Riding in the colder weather, I notice it does not climb above 13.5 volts. Is this a temperature induced situation?

I understand that the cells have lower efficiency in the lower temps, and that's what I think is going on here. I can't imagine a 9 month old battery with 3700 miles is going bad.

Thanks for the input here...

 

[ARtraveler]

You may have figured out the situation--but I will defer to those who know for sure.

 

[MikeinGA]

So, here's the deal...

I added the digital voltmeter to the left side guague location like a lot of us have done. During the summer, fully charged after 30 minutes or so of riding, the voltage reads 13.7 volts.

Riding in the colder weather, I notice it does not climb above 13.5 volts. Is this a temperature induced situation?

I understand that the cells have lower efficiency in the lower temps, and that's what I think is going on here. I can't imagine a 9 month old battery with 3700 miles is going bad.

Thanks for the input here...

Was the battery at the same voltage when you started out both times and the length of time they both went with out charging? I don't think that your battery is going bad. I keep mine on a Battery Tender. If the tender cannot bring the battery up to full charge it will blink red. Then I'll buy a new battery. Most motorcycle batterys last from 3 to 5 years if kept charge. That's IMHO.

Mike

 

[NancysToy]

It would be possible that your charging system has lost efficiency, or that the effects of a cold battery are affecting the voltage, I suppose, but I would think it is more likely a variation of the gauge due to temperature, or simple battery aging. Most measuring devices have a certain standard range that they are accurate in, and they drift from the mark outside that. I would not be surprised if your gauge is that way. The battery condition could affect the voltage, too. All batteries slowly die while in service. Yours may no longer be capable of accepting a full charge, due to sulfation or loss of lead in the plates. That does not mean it has gone bad or is unserviceable, just that it is aging. As long as it is above minimums, it is useable. Also, check your battery terminals (at the battery, not under the seat) for tightness and cleanliness. A resistant connection will affect charging and system voltage.

In my opinion you are being too picky. I would not sweat a tenth or two. One of the drawbacks to digital instrumentation is that for some applications they are just too precise. Owners fixate on the numbers and panic if they change in the slightest, or bounce from one digit to the next. One of the reasons auto makers moved to idiot lights instead of gauges, or gauges with ranges instead of numbers was the number of "complaints" that something was wrong because a gauge bounced or varied slightly, as well as the inability for the average owner to properly interpret the numbers. IMO, don't sweat the small stuff. If it worries you, though, pay your dealer perform a thorough charging system and battery test.

 

[FrankPa]

Thank You!

Thanks for the replies... I think you're ALL right... especially NancysToy.

I was a Radio Shack Manager in the 70's and the comment about 1 or 2 tenths is right on. And from statistics in college... is the difference between 13.5 and 13.6 because the voltage actually fluctuates from 13.59 to 13.60? THe possibilities are staggering... and insignificant!

Thanks again and...

HOPE TO MEET MANY OF YOU IN CUBA! (I'll be the guy on the Spyder!)

 

[Bob Denman]

Sometimes too much information is just that... :shocked:
I've always been the typical "anal-retentive; by-the-numbers" kind of looney. pps:
I've slowly learned (Somewhat) that there are always acceptable variations that have to be allowed...
So when that happens; I take a deep breath, bite my lower lip, an move on!

 

[billybovine]

Voltage regulator

System voltage when the engine is running is controlled by the voltage regulator and not the condition of the battery. Like any electronic item it can be affected by temperature. The shop manual states that the correct system voltage at 4000 rpm should be 13.0 - 14.8 Vdc.

 

[Arr MiHardies]

It could be that the wiring in your bike is becoming depleted of electrons and will need replacing soon. ....



:joke::roflblack:

 

[NancysToy]

System voltage when the engine is running is controlled by the voltage regulator and not the condition of the battery. Like any electronic item it can be affected by temperature. The shop manual states that the correct system voltage at 4000 rpm should be 13.0 - 14.8 Vdc.

Yes and no. The battery voltage and the circuit resistance do enter into the equation, as does the capabilities of the alternator/generator. The regulator keeps things within bounds, but it does not control the voltage to the nth degree.

 

[Bob Denman]

I think I like Arr's answer better... :roflblack: :thumbup:

 

[thehawk]

I always check for knots in the wiring. They slow down the electrons:joke:.

thehawk

 

[FrankPa]

Also...

I always check for knots in the wiring. They slow down the electrons:joke:.

thehawk

Same reason you can't pull zip ties too tight!

 

[Bob Denman]

:shocked:...
I don't know what you just said; but it sounded AWESOME!! :bowdown::bowdown::bowdown::bowdown::bowdown:
So... no knots and loose zip ties... :thumbup: :roflblack:

 

[Arr MiHardies]

:shocked:...
I don't know what you just said; but it sounded AWESOME!! :bowdown::bowdown::bowdown::bowdown::bowdown:
So... no knots and loose zip ties... :thumbup: :roflblack:

No no no... No tight zip ties.. They restrict the electrons like a kink in a hose.

 

[Bob Denman]

:shocked: pps: My Bad!
(Saw your pics... :bowdown::thumbup When are you installing the fusion reactor in the frunk for more electrical output??

 

[billybovine]

I have to disagree

Nobody has asked, but when did that ever stop me?

I'll ask & answer.
How does a vehicle voltage regulator work on the Spyder?

In order to understand that you have to know that the magneto/alternator requires a voltage to operate.
This voltage is applied to something called the field.

Without the field voltage the magneto/alternator puts out zilch.
With a voltage present it puts out the full 16V or so dictated by its design.

You typically want to keep the system voltage in the 13.5 to 14.2V range.

The voltage regulator sits with a sensor at the output of the magneto/alternator constantly checking the output voltage.
It controls the output voltage by applying a voltage or stopping the voltage to the field of the magneto/alternator.
What you have is a small current controlling the output of a much larger current.

Some regulators emulate the old mechanical regulators by simply cutting off/slamming on the field voltage depending on what output voltage it sees.
Other designs are more sophisticated but still basically do the same thing.

It's a feedback control loop from back to front.

By the wiring diagram the Spyder does not use a field coil to produce a magnetic field but permenent magnets that spin inside a coil. (Magneto) The coil produces three phase ac current that goes to a combo rectifier/voltage regulator unit. The rectifier changes the current to dc and the voltage regulator offers variable resistance to current flow to keep the voltage in set limits.

You description is correct if you are describing an alternator system in a car for example

 

[billybovine]

Just buy more

It could be that the wiring in your bike is becoming depleted of electrons and will need replacing soon. ....



:joke::roflblack:

Go to the auto parts store and buy a can of new electrons and make sure you buy the good ones, the ones from China are not as good. :roflblack:

 

[Questions]

Electrons

billybovine, right you are and wrong I am.
I didn't check the schematic before I launched in to my alternator/voltage regulator discussion.
I should have.

Thanks for making me get the book out. Sometimes it's too easy to just type a load of huey.

Along with that, please always get the most viable electrons when purchasing new ones. The problem that arises is similar to a marathon runner, the first 24 miles can be done nearly anyone however the last two are the killers, so when you get the new electrons go to the extent of checking your wiring, if it goes uphill to much that will put more strain on them and wear them out sooner. So inconclusion; no knots in wiring, no tight zip ties, and level your wiring. IMHO only!

 

[MarkLawson]

...HOPE TO MEET MANY OF YOU IN CUBA! (I'll be the guy on the Spyder!)

Oh, how embarrassing. I was planning to be on my Spyder too...pps:

 

[TuckMiddle]

Varying voltage

IMHO, all voltmeters are rather basic and probably not as accurate as a multi-mater of some kind. My Spyderd, depending on electrical load, rpms. length of trip so far, blah blah, sticks from 13.4 to 13.7. My Road Glide VMeter has a mind of it's own and works between 12.5 os so and almost 14, it's a needle gauge and doesn't jump all over like a digital.

This, y'all, is my entire knowledge of Voltmeters. Low is maybe bad and high is maybe ok or bad. At least it tells us that something good is more or less happening and that's a good thing. The digital oil pressure guage is ok also, but the numbers change so fast, you get to ignore it. 22 up to 80 psi, depending on so many things, I'm already 1/2 asleep thinking about it. The mx book has a cute little chart and what matters is minimum of 10 psi at idle and a max of 80 at 5,000 rpm. and normally while cruising around it's in the 40s and 50s.

Good night all, sleep like happy Giant fans tonight and in a month you won't remember who won anyway. But the Rumanian lady in the Fiat ad will be in your mind a lot - geez, what a honey. I guess I'll just cry myself to sleep!
:banghead:
Tuck