TOPIC:

Hi folks, I just made a homemade voltage rectifier using the schematic on Lou's site. I actually used the exact wiring shown in the "paint" version of the schematic with the positive and negative output connected directly to the battery.

Bike Running with field coil (low revs) connected - 11.3VDC
Bike Running with field coil (high revs) connected - 11.6VDC
Bike Running without field coil connected - 11.5VDC
Bike Not running - 12.5VDC
Voltage from 3-Phase Alternator Wires - 13.7VAC (Connecting negative terminal of battery and the wire itself with the voltmeter in AC mode)

So what the *%)#* is the deal here? Did I somehow ruin my VR (I know that it's wired right I've checked 8 times) or is my alternator just crap? BTW, when I connect the field coil, idle-speed RPMs go down (in other words, the alternator is taking up engine power as you would expect). Wheres my damn power going?



www.geocities.com/loudgpz/GPZdiy3phaseRectifier.html

Not sure,

I know the Stator is supposed to put out near or over 50 volts AC when you test across any of the 3 wires coming form the Stator. If not.... something is wrong with the stator. Regulator/rectifier controls the voltage after the Stator to charge the battery.

BTW,
It dont take much to damage the Stator. When I bought my bike the guy was cranking the heck out of it trying to get it started. He fouled the plugs, killed the battery, then tried jumoing it with his truck. That was enough to toast the Stator on the bike.

I see. Well I'll try to test the voltage across the alternators 3-phase outputs and see what I get.

Thanks

Few questions:

Have you double checked polarity of your diodes and also checked for open diodes with your ohmmeter?

That's all I can think of that would mess you up right off the bat.

It also seems to me that your A/C current is a little low, but maybe just because I'm used to bigger systems.

I'm not an electrician so may be missing something here but is'nt that design for just a rectifier ? All a rectifier will do is turn AC current into DC. I would'nt doubt Lous design or that you wired it correctly


A regulator on the other hand will determine the actual voltage ...........so.............I wonder if the problem you are having is related the your regualtor or your alternator ?

First, what bike are we talking about?

Second, a Rectifier (like the one on Lou's site) is exactly that, it rectifies AC into DC, it does not regulate the current or voltage.

You may be very lucky that it's not working, when rectifying 60hz ac to dc, the dc voltage is 1.4 * input voltage (not sure what it would be at the stators output frequency). Just think what 70 or do volts DC would do to your electrical componets

You "must" have a regulator.

1989 ZX1000 with an excited field alternator (like some earlier KZ's or nearly all CARS).

I guess I should have come with more background, this is a continuation of a project I had going on a long time ago
The plan was
1.) Get the regulator functioning, test by juicing the field coil and seeing the voltage bounce
2.) Install a standard Ford Mustang (65-86) external voltage regulator to regulate the voltage.

Now I got the idea for 1 from my clymers manual that suggests the same thing. Whether or not 2 actually works remains to be seen, I obviously need a working rectifier to test the ford regulator in this environment.

Steell, I doubt seriously that the voltage would surge to 70 (I could be wrong, I'm new at this, but thats a pretty big flaw even for Clymers). By your formula (AC_in*1.4=D.C_out) then I should be making 18VDC easily from my 13.7VAC 3 phase input, right? Or are you saying 18VDC PER input I.E. 54v?

In either case, I obviously don't have that much voltage but if I did for any appreciable amount of time probably everything would go boom.

So I guess what I really need to know is, how MUCH voltage _should_ I be reading from the AC outputs with the field coil on? >13.7VAC?

I'm going into the garage now to try to figure this thing out.

Post edited by: newbikekiller, at: 2007/10/27 22:30

jjdwoodman wrote:

Few questions:

Have you double checked polarity of your diodes and also checked for open diodes with your ohmmeter?

That's all I can think of that would mess you up right off the bat.

It also seems to me that your A/C current is a little low, but maybe just because I'm used to bigger systems.

I have checked for polarity, its voltage not current (although I think thats what you meant) and I haven't checked for open diodes. How do I check for open diodes?

A good diode will have different resistances depending on the way you connect the leads from the VOM. An open diode will read infinite both ways.

kzcsi

Ok did a few more tests
Carbon brushes - Good
Stator Coil Resistance - Good
Stator Coil continuity - Not exactly sure how to do this one
Rotor Coil Resistance - Good
Rotor Coil Continuity - Good


Original Rectifier - Bad
Original Regulator - Bad

Suspicious spots
1.) Stator Coil - my book says

Stator Coil Continuity Check
A.) Set ohmmeter on the RX100 scale
B.) Check continuity between the stator coil core and each of the coil windings. There should be no continuity
C.) If there is continuity, replace stator coil.

So what the F* is the stator coil core? They don't show any picture so I have no idea what thats supposed to be.

2.) Slip rings - I don't know what these do and can't test them without serious disassembly.

3.) Rectifier - testing for open diodes now

Thanks for any help. I am damn confused on this one.

Peter

Post edited by: newbikekiller, at: 2007/10/27 22:54

Ok I've tested the rectifier against the guidelines in my book (Which I assumes checks for open diodes). This is the procedure.

1.) Set ohmmeter to RX1000K Scale
2.) Ground one ohmmeter lead
3.) Use the other lead to check the resistance between between each of the 3 AC "in" connections
4.) Reverse ohmmeter leads
In one direction, ohmmeter should read more than 10X higher than in the other direction.
5.) Repeat 1-4 except check the resistance between the ground and the DC (+) out.

In my case, with my crappy ohmmeter, I read about 200 in one direction, and about 2000 in the other between the ground and the 3 "AC in" connections. I also repeated the test for the DC + connection and the 3 "AC in" connections and got the same result.
However, between the DC (+) and the ground, I read about 300 ohms both ways. I think thats pretty odd so I'm going to investigate more.

Post edited by: newbikekiller, at: 2007/10/27 23:16

Post edited by: newbikekiller, at: 2007/10/28 01:22