Charging System Failure Alert!!

[William_86]

Hello Everyone.

about one month ago, i had a friend's bike on the garage to help him change the stator. we couldn't find a suitable size alternator, machining the pieces needed would have been expensive than rewiring the stator. ($50 bucks) he decided to pull the engine.. well long story short. What a big mess and a PITA to have an stator failure. I was riding with him. and lucky we were riding around town other friend of us swapped batteries with him so he could drive to my place to check the bike. as you know. he noticed the failure untill the bike just died on a red light. the headlamp started flashing (HID ballast) bike started to sputter and south the went :|

When i first started reading about the 1200s weak point i installed a voltmeter on the fairing. but as everyone here told me... you wont look at it unless something is wrong. it wont alert you when the bike stops charging the battery so you have enough time to decide what to do before your battery gets discharged.

so with both things in mind. i had been playing with electronic projects (for fun) i was bored with nothing in mind so i thought i could find some instructions to build something that would alert me when the bike would stop charging the battery. i started googling and it wasn't hard to get to this article: 12 Volt Low Battery Indicator .

This is a very simple circuit that will lite a LED when the input voltage its below a fixed selection. with a variable resistor you can regulate the point where the led lites.

The diagram:


all the parts were worth about $2 bucks.

• The integrated circuit its an LM741 operational amplifier
  
• The Zener diode should be chosen with a zener voltage of around half that of the target voltage - e.g. for a 12.0 Volt indicator, a 5.6 Volt Zener diode could be used. I went for the next value available since our batteries usually run at 13V
  
• instead of the 500 Ohms resistor for the led i used a 330ohms to make it light brighter.[/list:u]
  
  its a very easy straight forward circuit that anyone with soldering skills can do (like me)
  
  I first tested it on a protoboard and worked as supposed, i was using the 500ohm resistor on the led thats why it looks that dim and on the final circuit used an smaller variable resistor.
  Here is the test video, with the bike idling the voltmeter reads 12.90-+ Volts, you turn the pot all the way till it goes off. then slowly turn it counter-wise until the led lites on.
  
  [size=150]Video[/size]
  
  I overloaded my charging system by triggering the brakes (about 90+ watts with regular bulbs) Driving lamps (70W) causing the voltage at the battery to drop under 12.8
  
  once the circuit was tested. i used a cooper circuit board to make the definitive gadget. here some pictures of the welding so you can make your own.
  
  
  
  
  *Forgot to draw the 330 ohm resistor but you can see the pins where its weld sorry:*
  
  i've tested it and the smaller variable resistor its more sensitive, led lights very bright. ill install it as soon as i can, LED will be installed in the dash.
  
  I Hope you find this useful, for less than $10 with the cooper board, wiring/terminals its a very cheap useful gadget. feel free to ask any questions

[roscoepc]

Pretty neat device William, Thanks!! 8)

[Roleketu]

Great for those with electronic skills, but for me I just use DIGITAL 5 FUNCTION VOLT METER. It displays battery voltage when bike is not running, then charging voltage when running, also just above the voltage readout is three led lights, red-yellow-green that light as your voltage changes.

[Guest]

I have this mounted right by my ignition switch and tells me at a glance what is going on with my battery. It also has an audible alarm to inform you of over charging and under charging. I paid around 40 bucks for it.It has a 6 foot cord to easily hook it up.
http://besabattery.com/pdf/Argus_Analyze...ry_Bug.pdf

[William_86]

voltmeters but yet again, on the daily basis you wont pay attention to it until the bike dies just to notice the batery has discharged i have a voltmeter too and a couple of weeks after i installed it i forgot it was there

[Roleketu]

I have the voltmeter I linked to velcro'd to the cassette player door. It's right in front of my face and see it always. Including the LED warning lights for night time. And the air temp thermometer is quite nice too.