electrical

[ard]

Hello everyone, I was talking to an old friend, who said he knows alot about GSs, and he worned me of blown light bulb, He said if I get a blown bulb and dont change it I will have burnt altornator or regulator or stator. is there any thruth to this. and if there is, how can I prevent the melt down?

Ard 8O 8O

[Anonymous]

lamps

it does seem odd that that situation would cause the alternator to short out,
after all your removing a slight load on the part?? In my opinion that would only be a problem if you had a major short!!

[Anonymous]

If your lighbulbs start burning out on a regular basis it means you're overcharging the battery or using really cheap bulbs that break when you hit bumps. If your charging over 14 volts you're got a problem. Low 14s is preferred but it's not something you can control without getting a new Rectifier/regulator.

You're friends comment doesn't hold a lot of water with me considering that you don't have all of the lights on all of the time. You can turn the blinkers on and off whenever you want. Yeah, the battery voltage will be higher with all the lights off but not substatially.

Steve

[earlfor]

The normal charging voltage range for a 12 volt motorcycle is 14.2 to 14.8.
Up to 14.9 is permissable if the battery water level is checked and topped up regularly. Design point optimum (according to Electrex) is 14.7 volts
A 14.7-14.8 charge rate does not reduce lifespan, or cause bulbs to prematurely burn out. The regulator/rectifier rectifies the Stator AC voltage to DC and then "gates" the high and low voltage rate to match electrical pressure in the system (battery voltage). The system will self balance to a set input wattage up to the max capacity of the rectified stator output. Turning lights on and off will not change the charge rate as long as the capacity of the charging system is not exceeded by the draw. Stator output increases with rpm, but at aprox 5500 rpm the R/R high side gate limits the DC output to 14.7-14.8 volts and shunts the excess to ground where it is converted to heat and dispersed by the cooling fins on the R/R. There is no reason I can think of that would indicate a burned out light bulb would have any harmful effect on the charging system. Up until 1979, all motorcycles had on/off switches for the headlight and dash lights as manufactured and there was never a problem with the charging systems because of running with the lights off. (lights on were not required in those days)

Earl

If your charging over 14 volts you're got a problem. Low 14s is preferred but it's not something you can control without getting a new Rectifier/regulator.

You're friends comment doesn't hold a lot of water with me considering that you don't have all of the lights on all of the time. You can turn the blinkers on and off whenever you want. Yeah, the battery voltage will be higher with all the lights off but not substatially.

Steve

[Anonymous]

ah, I meant 15 volts when I said over 14.

Steve

[Anonymous]

Blown Bulbs

There may be some valitity to your friends claim about blown light bulbs causing electrical problems. The alternator is a 3 phase device producing about ~70vac per phase. Phases 1 & 2 are always applied to the bridge rectifier. Phase 3 is not connected until the headlight switch is turned on. With the lights off and 2 phases supplied to the R/R there is adequate power to keep the battery charged and the R/R happy and cool. Now turn on the headlights and you are adding 33% more power to the mix. The light bulbs consume this additional power and the R/R is again happy and cool. Blow a bulb or 2 and where will this abundance of power go? Thru the R/R to ground. The R/R is no longer happy and surely not as cool. Heat is the enemy of electronic devices. This is when your electrical problems will start. Replace those burned out bulbs.

[ard]

I am so fascinated, with the respondes from the group, and the points that everyone makes is very comforting and very logical. Thank you all for your input.I think I am in touch with the worlds most generous and knowledgable friends.