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alternator output voltage?
Posted: Fri Dec 12, 2008 5:51 pm
by leopard_pagan
what should a healthy NC29 alternator (generator) be sending the reg/rec?
mine with bike running is 2 volts!
Re: alternator output voltage?
Posted: Fri Dec 12, 2008 6:59 pm
by CMSMJ1
ooops LP - sounds knackered!!
Should be over 12v otherwise the battery would discharge all the time.
What is it with the engine revved to 5k revs and measured across the battery?
Re: alternator output voltage?
Posted: Fri Dec 12, 2008 9:24 pm
by wullvfr
the problem here is if you are checking the voltage output of the alternator before it reaches the reg rec then you have to switch the multimeter to ac voltage.................
the output of the alternator@5000rpm should be 50volts or more.
to check voltage at the battery it should be set to dc volts and the readings @5000rpm should be between 13.5-15volts.
william
Re: alternator output voltage?
Posted: Sat Dec 13, 2008 8:56 am
by leopard_pagan
battery with no engine running- 12V
battery with engine running at idle -12V
battery with engine running reved up -12V i know it should go up at this stage.
Reg/Rec voltage input while bike on idle from genny- 2V
Reg/Rec voltage input while bike revving from genny- 2V
under the tank is a plug that leads direct to genny to remove reg/rec from equation... while engine is on idle-2V, and the same while revving!
BTW this was tested by a auto electrician who rides a ducati so he knows what multimeter setting he needs + i was there working with him.
i know i have put my genny through some hard work, for 3 years i ran 100/80W X 2 bulbs. the same auto leky shop told me that at night.. brake lights on,sidelight, indicating and headlights on high beam. ALL the power from the genny is going out to the bike, none is going to battery. THIS is the main reason i started looking at LEDs as alternatives as they use minuscule power to work. for the last year i have had the HID ballast kits on which are supposed to run 35W each bulb, however the ballast generate 24,000Volts...
Re: alternator output voltage?
Posted: Sat Dec 13, 2008 9:05 pm
by Waza4
It's not your hid's the ballast pack is just a step up transformer because it's more efficient to run high voltage at a low current.
You have proved no charge so now you need to unplug the alternator and give it a resistance test on the yellow to yellow all 3 of them and then each yellow to earth there should be no continuity (each yellow and the earth should stand alone )
And the same for the reg/rec yellow's should be 30-500 ohms.
yellows to green 10-200 ohms
yellows to red/white no continuity
Get yourself a meter.
Its all in the Manual. Electrical Systems: Alternator stator coils
Reg/reg unit check and replace
There's only so much you can test with the engine running, witch is a worry if your paying the guy!
Re: alternator output voltage?
Posted: Sun Dec 14, 2008 1:07 am
by wullvfr
the alternator puts out alternating current so the multimeter must be set to ac volts.........the voltage output of the alternator has to be at least 50 volts..................you take three seperate readings as it is a three phase alternator(3 pins)
also a fully charged 12volt battery will read more than 12 volts at idle or switched off.
usually a battery with a minimum of 11.7 there abouts will struggle to turn over the engine.
william
Re: alternator output voltage?
Posted: Sun Dec 14, 2008 1:55 am
by wullvfr
if you have tested the output of the alternator correctly and it is showing low readings like you have said then it is well and truly goosed.
when mine was past it,it was showing 3 seperate readings of around 30 volts.this output was enough to charge my battery whilst not using any lights but if i did use my lights then the battery would drain faster than it got charged.
the charge rate at 5000rpm was just under 13 volts.....12.7 i think.
when i removed the alternator you could see that it was burnt out!!!!!
william
Re: alternator output voltage?
Posted: Sun Dec 14, 2008 11:04 am
by leopard_pagan
may i remind people...."this was tested by a auto electrician".
the company i use is a long established family run auto leky shop. all the people who work in it are bikers who i am sure know their way round multimeters. + i do know he did check resistance readings as i was there when he did the checks.
bike is now in a bike shop for several jobs inc fit an alternator, valve clearances, balance carbs, nee a new choke cable. and health check
Re: alternator output voltage?
Posted: Sun Dec 14, 2008 7:28 pm
by wullvfr
well if it was tested by a auto electrician what conclusion did he come to?
if the alternator is putting out 2volts then that is a well fucked alternator.......
william
Re: alternator output voltage?
Posted: Sun Dec 14, 2008 7:36 pm
by Waza4
Well why didn't you say that you had a resistance test done.
So are you second guessing the guy, obviously not by your last comment.
So this must be LP's Christmas Quiz.