We need a FAQ on Battery Voltage

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Yeah I have to agree....

I have found that some think they are gods in the presents of us mere mortals.

Just tell them to stick it! the spoon where the sun doesn't shine!!!!! :lol:

No all kidding aside, I would just ignore the replies that you have not asked for and scan through your post until you find what you are looking for or you can always pm those that you think will help you out... there is nothing like being frustrated with something and then reaching out for a quick helping hand and getting the smack down that occurs all to often on this board!

Please forgive me if I have offended anyone! :p

Just stuck at work no days off left for the rest of the year! :cray:

 
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The FJR stator generates a high voltage AC output which reaches peak current from 5k rpm and up. The Rectifier/Regulator (R/R) converts the AC into DC at a voltage in excess of 14.5 volts. The regulator dumps all the excess power to ground, leaving ~14.5 volts DC on the output terminals of the regulator. The power that gets dumped to ground makes the R/R always run very hot. The Gen I stator & R/R system is rated to produce 35 amps at 14.0 volts at 5k rpm = 490 watts. Anything less than 5k rpm will produce less than 35 amps. A fixed power load that is acceptable at 5k rpm may overwhelm the charging system at 1k rpm (idle) because the stator's current output will be very low.

The battery would like to have a minimum of 13.2 volts to maintain a light trickle charge. Ideally, you would like to see the voltage at the battery terminals running 13.7 to 14.5 volts. In this sweet spot the stator is supplying sufficient current to maintain battery charge and sufficient power to run the electrical devices on the motorcycle without incurring an overheating condition.

When you see 12.8 volts at the battery terminals it indicates that the motorcycle's charging system has reached the end of its capability to supply sufficient current, and the battery is on the verge of supplying 'make-up' power. By 12.4 volts the charging circuit can no longer supply sufficient current, and the battery is starting to supply 'make-up' current and the battery is now slowly being discharged. The more significant event is that the stator is actually over-loaded and getting very hot, entering a zone where it can become permanently damaged.

With a good charging system, and a healthy, properly charged battery I would offer these guidelines for sustained voltages:

≤12.8 volts at the battery terminals – the charging system is over taxed, the battery is being discharged, and the stator is in danger of being permanently damaged.

12.8 to 13.2 volts – entering the danger zone, the battery is no longer being trickle charged and the stator is being taxed to the limits.

13.2 – 13.7 volts – undesirable but sustainable, the stator is taxed but the battery is being charged.

13.7 to 14.5 volts – schweet

15.0 and up -- the battery is being damaged a.k.a. cooked

12.7-12.8 volts – good battery voltage when it is fully charged and disconnected from the motorcycle; measured at 70°F

 
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And there is an example of what folks on this board are capable of! I don't know Alan from Santa, but having read many of his well-reasoned and informative threads, I'm taking this one to the bank!

Thanks ionbeam. :clapping:

 
This is one of the best and most on target posts I have seen. :yahoo: thank you ionbeam :yahoo: I am adding heated gear this winter and have done multiple searches without actually being sure of the facts. I kind of thought I understood what I needed to watch with my electrical system as I added farkles, but I was not sure. Your combination of explanation and actual numbers is very helpful. This should be made a sticky in the FAQ section. It would have saved me lots of time doing searchs.

The FJR stator generates a high voltage AC output which reaches peak current from 5k rpm and up. The Rectifier/Regulator (R/R) converts the AC into DC at a voltage in excess of 14.5 volts. The regulator dumps all the excess power to ground, leaving ~14.5 volts DC on the output terminals of the regulator. The power that gets dumped to ground makes the R/R always run very hot. The Gen I stator & R/R system is rated to produce 35 amps at 14.0 volts at 5k rpm = 490 watts. Anything less than 5k rpm will produce less than 35 amps. A fixed power load that is acceptable at 5k rpm may overwhelm the charging system at 1k rpm (idle) because the stator's current output will be very low.
The battery would like to have a minimum of 13.2 volts to maintain a light trickle charge. Ideally, you would like to see the voltage at the battery terminals running 13.7 to 14.5 volts. In this sweet spot the stator is supplying sufficient current to maintain battery charge and sufficient power to run the electrical devices on the motorcycle without incurring an overheating condition.

When you see 12.8 volts at the battery terminals it indicates that the motorcycle's charging system has reached the end of its capability to supply sufficient current, and the battery is on the verge of supplying 'make-up' power. By 12.4 volts the charging circuit can no longer supply sufficient current, and the battery is starting to supply 'make-up' current and the battery is now slowly being discharged. The more significant event is that the stator is actually over-loaded and getting very hot, entering a zone where it can become permanently damaged.

With a good charging system, and a healthy, properly charged battery I would offer these guidelines for sustained voltages:

≤12.8 volts at the battery terminals – the charging system is over taxed, the battery is being discharged, and the stator is in danger of being permanently damaged.

12.8 to 13.2 volts – entering the danger zone, the battery is no longer being trickle charged and the stator is being taxed to the limits.

13.2 – 13.7 volts – undesirable but sustainable, the stator is taxed but the battery is being charged.

13.7 to 14.5 volts – schweet

12.7-12.8 volts – good battery, fully charged, disconnected from the motorcycle, 70°F
 
If you need an extra 55 watts, just unplug the left headlamp. Daytime of course.

Left is easier to access.

I've done it 2 up, heated gear. Adds enough to keep the battery charging. 2 vests 90-100 watts.

1 headlamp 55 watts. Datel stays above 13.4 , vests maxed out.

 
A little off topic but, does anyone know or tested what a typical HID setup pulls for replacment of the normal headlight bulbs?

I've "heard" it is less but not if it is true or by how much.

 
Hey, whatever happened to faster675? I don't see him hanging around this post any more... :rolleyes:
He's here, he's doing just fine. We've been chit-chatting via PM the last few days. B)

A little off topic but, does anyone know or tested what a typical HID setup pulls for replacment of the normal headlight bulbs?
It is true, but the savings is not massive... though every little bit helps.

Each HID setup (One ballast/ignitor and DS2 bulb) consumes ~ 42 watts.... a 13-watt savings over it's (lo-beam) halogen equivalent.

Specifically: ~ 35-watts for the DS2 bulb (once up to temp), and ~ 7-watts to keep the ballast humming.

Therefore, a twin HID setup in place of your normal 55-watt halogen low-beams saves you ~ 26-watts.... which will run a Widder vest at 50%, or a set of heated handgrips on the "low" setting. B)

 
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Hey, whatever happened to faster675? I don't see him hanging around this post any more... :rolleyes:
He's here, he's doing just fine. We've been chit-chatting via PM the last few days. B)

A little off topic but, does anyone know or tested what a typical HID setup pulls for replacment of the normal headlight bulbs?
It is true, but the savings is not massive... though every little bit helps.

Each HID setup (One ballast/ignitor and DS2 bulb) consumes ~ 42 watts.... a 13-watt savings over it's (lo-beam) halogen equivalent.

Specifically: ~ 35-watts for the DS2 bulb (once up to temp), and ~ 7-watts to keep the ballast humming.

Therefore, a twin HID setup in place of your normal 55-watt halogen low-beams saves you ~ 26-watts.... which will run a Widder vest at 50%, or a set of heated handgrips on the "low" setting. B)

Dale, Thanks for the reply.

Is the ballast saturation power requirement "pretty fast" (like a few seconds) or is it a temperature threshold?

Seems as though you are pissed at me about the bag liner thread?

 
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