charging circuit or battery ?

ok here we go. i received a good second hand stator with a standard loom. it checked out good i.e approx 0.5ohms between the 3 phase wires and no short to the casing. i also buzzed out the inner brush wire (black) and the outer brush wire (green) both good. I have installed the stator and wired with the nylon screws isolating the inner brush and connecting that to switched power. The outer brush i connected to the reg/rec green wire. All buzz out fine. If a check the resistance between the brushes i see 10.6 ohms and i see good continuity from the wires connecting the brushes to the rotor tracks. so i thought i would do the voltage test across the brushes with the ignition on i have 12.1v at the battery but nothing seen at the brushes ???? previously with the old stator i saw approx the batt voltage -2 volts so i know the rotor is ok. Could this be the reg/rec i.e its not switching the green output to 0v ?? is it possible to check the reg/rec by voltage testing the reg/rec green wire to batt positive with the ignition on ? , the loom for the stator had 2 spare wires , yellow ( leave disconnected) and a blue wire ???? any thoughts
 
You say you have a black wire on the inner brush and its wired to switched power. Connect your VOM meter leads to the inner brush (black) and to alternator frame. When you turn on the key, do you measure battery voltage?
If you do see battery voltage there, measure the voltage between the 2 brushes.
Make sure that the rec/reg unit is grounded to bare metal on the frame.
 
cheers retiredgentlem, i will give it ago tomorrow, if the reg/rec is toast i was thinking of sticking the old separate reg and rec on. i have a stanley regulator with 2 wires one yellow or white and one black or brown so if things don't look good i will see about regressing. the current combined reg/rec does have a black wire going to batt negative but do i also need it chassis grounded to its case. i guess its possible i saw a voltage with the old stator as it was clearly shorted maybe that gave me the voltage reading.
 
ah just remembered earlier when i was testing i shorted the inner brush to chassis with the VOM probe with the ignition switch on ………………….nice big spark so i guess that means batt positive is getting to the inner brush. so unless the reg/rec is toast could it simply be the reg/rec frame ground ?
 
i will try it in the morning, just out of interest should i have the black wire from the reg/rec going to the batt negative terminal ?
 
Some rec/reg units have a black wire coming out of the case. Some others do not, and you might have to add a black wire from the rec/reg case going to the frame bare metal. It should not be necessary to have a ground wire running directly to the battery negative. The battery negative normally has a large cable (strap) going to bare metal on the frame. So as long as the rec/reg unit has a black wire connected to bare metal, then all is well. The frame provides the path back to the battery negative, so really no need to have an additional wire.
 
i will check tomorrow the reg/rec case to ground, that black wire i connected to directly to batt negative i suspect is providing the case ground but i will check. if the case is then i can't see any reason for not seeing a voltage at the brush inputs other than the green reg/rec output is duff, all wires buzz out correctly
 
couldn't resist it so just checked………… that black wire isn't providing a case ground on the reg/rec so no idea what its for ? the reg/reg is coated on something grey which is conductive so yes i need to provide a bare metal case connection to frame or direct to ground which i don't currently have. I am still puzzled what that black wire is though could it be the regulator side of the unit ground although can't imagine why they would be separate.
 
i know this is rambling on but i now think that possibly this *(^&*^% reg/rec wiring is actually green earth etc etc thats the only way i explain that black wire i.e. it is actually possibly switched power to the outer brush in a normal non nylon screw setup. As i just cannot find any wiring for the damn thing I'm going to install the separate reg and rectifier. So i have the below and what think connects to where if i do away with the nylon screws:-

Regulator Stanley
1. yellow/white ------- outer brush
2. Brown/black ------- switched power after ignition switch
3. I assume case is grounded

Rectifier
3 x white ----- 3 phases
1 x red -------- battery positive
1 x brown ---------- switched power
1 x black ------------ inner brush ????? as the inner brush is now grounded via the stator housing this wire is feeding ground unto the rectifier ?????? why if i ground the rectifier directly ???
 
I can't help with the Stanley regulator, because I have never seen one. They must be used only in the UK.

Rectifier:
3 whites and 1 red are fine as mentioned. There is no switched power used in a rectifier, so no idea why you have a brown wire.
Black wire should just be connected to bare metal on the frame (not the battery box because its rubber mounted).
No need to run a black wire from the rectifier to the inner brush. As you said, the inner brush is grounded via the steel screws to the stator housing.
 
I wonder if i actually need a regulator as i have no accessories other than a horn i.e. no lights etc, so maybe i can get away with simply running switched power direct to the outer brush then as you say simply have the 3 phase wires to rec / red from rec to batt / black from rec to ground. hey presto. i think i can see what the regulator is doing i.e. it simply sits between switched power and the outer brush i.e. almost a valve allowing more or less juice to the alternator . as i only have 2 wires i guess i could wire it in one wire to switched power after ignition switch then the other to the outer brush. then with ignition on i should see a voltage at the brushes if not i simply swap the regulator around.
 
If you run a battery then you will need the regulator.

The regulator controls the power going to the field winding (rotor) which in turn determines the voltage exiting the alternator and hence the rectifier. The optimum voltage to charge the battery is approximately 14.3 Volts. The regulator is preset to give this 14.3 Volts at the battery. If the voltage is lower than 14.3 Volts then the battery charging rate decreases. If greater than 14.3 Volts then the charging rate will increase a bit more but the rate of water electrolysis starts to increase rapidly. At about 14.7 Volts the electrolysis of water to hydrogen and oxygen is getting quite high.

The result of electrolysis is the acid level in the battery cells starts to drop faster as the water is removed. The venting of the hydrogen and oxygen produced is likely to carry acid down the battery vent pipe and this acid will end up on the bike and cause some surface damage.

Batteries run at too high a charge voltage have been known to distort from heat and in some cases fracture. Higher voltage charging requires more attention to the acid levels in the cells where as at 14.3 Volts this is not such a big issue.

The regulator also ensures that the other electrical components receive a voltage appropriate to their specification. Running power direct to the alternator from the battery is something you only do as a system test. If you do this permanently then the voltage output from the alternator will be higher and higher as the revs increase and something electrical may fail.

Edit: I had a friend who had no regulator or lights and was happy with everything. He had no battery so I think the bike had a magneto - but you have a battery to deal with.
 
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ok thanks ……… i will try to wire as i said but these components are confusing i.e. the 2 separate components that came off the bike i.e. when the stator had a standard setup no nylon screws i believe from memory were wired , they both look solid state. As mentioned before the rectifier has a brown wire ??? but no green so i assume its not actually a combined reg/rec. I will wire up the regulator and see if i get a voltage through it.
 
how hard can it be to install a regulator with only 2 wires ?????? when i connected the reg black lead to switched power and the case to ground it blew the main fuse. When i connected the yellow to switched power and the case to ground no voltage was seen out the black lead ( installed new fuse) can anyone recommend a psychologist or a reg/rec that can be used with the nylon screws and wires straight into my stator loom
3 x white 3 phase
1 x red batt +
1 x black inner brush
1 x green outer brush
1 x blue - no idea blank off
1 x yellow blank off
 
Personally, I would scrap all the "mystery" components you have and switch to ones that are known to work. That would be an automotive regulator and a 3 phase rectifier from the electronics world. Your "mystery" stuff may be functional but you simply don't know how to make it do so. It's also possible they are the wrong components for your type of charging system. They may even be responsible for your burnt out original stator.

If you stay with the nylon screw mod, you will need an automotive regulator that switches ground, one with what they call a type "A" circuit. Many use a VR295 but there are lots of substitutes ...

VR295 Ignition Voltage Regulator
also known as:
VR125
R296
VR733
AL154
VRA383HD
CH543
VR8638

Another nice little substitute is the VR794 from a Fiat. This is a small unit, less than half the size of the others and encased in an alloy heat sink .....

http://www.ebay.com/itm/122128766123?_trksid=p2060778.m2749.l2649&ssPageName=STRK:MEBIDX:IT#shpCntId

A drawing for the unit clearly labels it as a type "A" and explains the wiring .....



For a rectifier, many of us use these. You need a 3 phase unit with a 25A or greater rating .....

http://www.ebay.com/itm/151314178350?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT

If you search the UK eBay listings, I'm sure you can find this stuff at a reasonable cost.
 
i have been doing some research, i think the regulator that came off the bike (Stanley) is simply regulating the voltage on the harness after the alternator i.e. it just sits across the batt positive and negative. If this correct then you might be right 5twins as it would not be controlling juice into the stator but rather controlling voltage after it could have burnt out the stator i guess. Still can't find that regulator in the uk
 
Yes, that rectifier will work, but you should be able to find one cheaper .....

http://www.ebay.com/itm/Bridge-Rect...560392?hash=item4b0bebf588:g:naYAAOSwXeJYIwjf

Be aware that the rectifier gets hot in operation so you will need to mount this plain type on a heat sink of some sort. I'm using this type at the moment and mounted it on a section of heat sink from an old computer .....

Rect4.jpg


Also, as you can see, the wiring connections should be clearly marked on the side of the unit, but here's an explanation .....

35amprectifierlabeled.png


Yes, if you use a "B" circuit type regulator, you will need to switch back to the original steel brush mounting screws and wiring. The "B" type switches power on and off to the outer brush to control the charging output. Yes, the "B" type has 3 wire connections. One pin is ground, one is switched power in from the harness, and one is power out to one brush. If you keep searching, I'm sure you'll find something .....

http://www.ebay.co.uk/sch/i.html?_o..._nkw=fiat+vr170+voltage+regulator&_sacat=6030
 
If you use the wrong components, the damage may not be immediate but will probably happen eventually. A local kid I help had the wrong regulator on his '78. He had the later type "A" ground switching unit. It shouldn't have worked at all but somehow the P.O. wired it in so it did. But the charging output was way too high, well above 15 volts. I told him that wasn't right or OK. He asked someone at his work and they said it was fine. He decided to take their advice instead of mine. He got about 600 miles on the bike before the charging system fried. An initial $10 to $20 repair had now grown into a $100+ one because he fried his rotor.
 

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