Topic: regulator... rectifier... again! :)

[dave500]

dont let your skin touch the test terminals also,most decent units will detect this and give a false reading,most likely the auto ranging type,that or they wont settle into a steady reading.

[auro]

If your meter is reading 1 all the time, even with the tips of the leads shorted together, the meter is not working properly.

guys - thanks!

to clarify, I put the voltmeter in "resistance" check mode, then connect one lead to one of the terminal sockets and the other to another one (each one is an endpoint of a yellow wire). then I get a 1, otherwise the voltmeter gives me a 0

[Fritz]

then I get a 1, otherwise the voltmeter gives me a 0

This is strange, you know. A 1 means "infinite" or "too large to measure". A 0 means "no resitance".

Check if your test leads are correctly connected to the multimeter. The black lead should be connected to "Common" and the red one to "VΩmA".
Now switch to "Ω, 200" (six o'clock position).
Now hold together the tips of the two test lead to measure internal resistance. You should read something between 0Ω and 0.5Ω
Write down this number.
Now hold your test leads to any combination of the two yellow wires coming from the stator.
You should read something between 0.35 and 0.45 Ω, I think. Substract the number that you have written down and you've got the resistance of your stator coils.

[auro]

thanks

will do

news later tonight or tomorrow.

the saga continues 

[TwoTired]

What does yours read?

as said, "1" - which looking at the multimeter manual means... over-range?

Maybe there is a translation problem, here.
If you touch both probe tips together, without measuring a circuit component, and the display reads "1", then the test equipment is faulty, becasue we know that a direct short should be zero ohms.   It could be leads, probes, or something internal that is failing.  The possibility exists that if that function doesn't work in the meter, then neither is the rest of it without a calibration test of the needed function.
Given this possibility, none of your reported measurements have significant meaning, and you must start over from the beginning with known good test equipment.

Why not tell us the brand and model of the meter, as they are not all the same.

here it is:
http://www.amazon.co.uk/DIGIFLEX-Testing-Digital-Multimeter-Voltmeter/dp/B003NEGZLS/ref=sr_1_1?ie=UTF8&qid=1344415100&sr=8-1

Can you find us a link to the owner's manual that came with the unit?
Perhaps we can help with a repair of the unit, if an internal fuse has been interrupted.

A faulty lead/probe can be tracked down by inserting a separate wire into the red and black sockets while on the ohms scale.  Recall, a direct short is zero ohms (physics).  The meter must read very near that, commensurate with its accuracy rating.

Cheers,

[auro]

hi all - thanks for your input.

I re-did the test yesterday evening and got 0.7 ohms with both probe tips together.
I get a 1 when I hold the test leads to any combination of the two yellow wires' connectors (in the frame's wire loom, where the reg/rect should connect, and this is done when the bike is running at idle)

does this make any sense to you? what could that mean?

[TwoTired]

If I understand correctly you are measuring the stator winding at the connector to the rectifier.

If so, your tests indicate the stator windings are open, OR the wires/connection between the rectifier plug and the stator winding are open.

However, resistance tests are never done to an active circuit, as the meter injects a small voltage into the circuit to perform a test, an active circuit will baffle the test meter with voltage it did not inject.  Only voltage and/or current tests are done on an active circuit.

Check the resistance of the yellow stator wires with the engine stopped and key switch off.  If you still measure the yellow wire going to the rectifier plug as infinity (over range), then you will have to find the breaks in the wires or connector between the rectifier plug and the stator itself.

[auro]

again thanks for the tips

I will try to redo the test today or tomorrow with the engine stopped and the key switch off, as you suggest, and will come back with news...

[Fritz]

Hi Auro,

you should never measure resistance in a powered circuit.
Furthermore, before testing the stator, you should disconnect it to eleminate possible problems with the rectifier or regulator that might throw your numbers off.

Please read the service manual for your bike first:
http://www.sohc4.net/index.php/cb550/books-manuals-guides-2/
In part 4 there's a description of the procedure to test the electrical components.
Page 95 is about the generator.You do not need to/should no disassemble the generator, but you should disconnect it from the harness on the "electrical plate" under the left side cover before taking your measures.

After reading your posts again, I think that nothing is wrong with the generator.
But it's good if you practice the diagnosis described in tha manual anyways
As TwoTired LLyod already said, the generator's output is not that huge. Your battery does not charge if the bike is just idling. You should also fear stop-and-go traffic if your battery is not fully charged. Also, if you are riding in city traffic most of the time, try lower gears and rev it above 3500 rpm from time to time or do some miles on the highway.

What I do think is that you should go through and clean all your connectors: headlight case, ingition switch, main harness under fuel tank including ground connection to frame, connectors under left side covers, tail light harness under seat.
Pay special attention to the ground connection near ignition coils and the one between the battery negative cable and the frame.
Also, clean the fuse holder: Take fuses out and polish the clamps that hold them. I like  "fibreglass pencils" to clean contacts: http://www.maplin.co.uk/abrasive-fibreglass-pencil-3932
After cleaning the connectors, you can apply small amounts of dielectric grease to inhibit corrosion in the future. You should replace weak connectors or try to "retension" them with pliers.
Following this procedure, your numbers should read higher.

Cheers
Carstens

[auro]

again thx to all

here is my panel:


and the reg/rect - alternator connector:


i did the ohm test with the bike's engine off and key turned off
i still get a 1 on the meter
when i have the probes of the meter to touch each other, the scale goes down from 1 to ~0.6
when i have the probes inserted into the connector, for the yellow wires, it stays to 1

not sure how clearly this can be seen in the (low quality) video i took => resistance

so right now i'm not sure what to do - check the cables or go for a ride (the battery is at 12.35V) and see if it recharges by keeping it a bit on the high rpms level?

[TwoTired]

Your meter probe to plug connection points are off camera.  So, we have to assume you are using the correct pins on the plug AND that you are inserting the probe tips in far enough to make a connection to the terminals.  If you are sure about those two uncertainties, then you have to pull off the sprocket cover and follow the yellow wires to another plug there for the stator connections.  Your meter is saying there is an open connection, and you now have to fine out where that is.  We can't tell if that is from a poor connection made at the plug terminals for your meter, at an interconnection plug under the sprocket cover, or the stator itself.  It is unlikely the stator itself unless it has suffered some physical trauma.  Follow the yellow wires back to the stator and look for or measure for breaks in the electrical pathway.

[Fritz]

In a previous post, you said

battery fully charged, as said, read 13.3V
again, when I start the engine up it goes down a bit, but revving up shows more current getting to the battery, up to 13.5V @ 4000 rpms, but not more, and starting at 12.1V at idle.

So the generator is actually working - to some degree at least.

Now if you measure an open circuit for all three stator windings, that's contradicting to what you wrote above.
There must be something wrong with the way you measure the stator.

First of all, you should know that the stator windings are only connected to each other and nothing else. So if you measured between green and any yellow, that would explain this contradiction. This measurement should surely read "1" aka open connection, showing you that the coils do not short to ground.

The correct measurement is taken between any of the yellow wires:
1st measurement between Y1 and Y2
2nd between Y1 and Y3
3rd between Y2 to Y3

[auro]

guys - you are of invaluable help!

I certainly do not measure this with any green or red wires - only the connectors related to the yellow wires, that's for sure.
Apologies for missing out on the part where I connect to those, in the video, I can try to take another pic/video soon.
I tend to agree that, given the previous measurements taken with the RPM test, it might be that all is working but I'm either failing to test resistance correctly or my voltmeter is bugged

What I can do is:
- try the bike on the road as said, check if it actually recharges the battery if I drive at higher RPMs for a while
- test resistance at the connector (yellow wires) by changing the way I insert the probes, see if the meter detects anything this time 

if all of that fails, i'll buy a spare battery to keep with me when I go for long rides 

[auro]

update

test on the road last Saturday:
- started with the bike's battery giving me 12.36V (engine stopped, ignition key off)
- did 20 kms, most of which above 4K RPM
- when back battery gave me 12.03V (engine stopped, ignition key off)

 

I will take time to test again resistance at the yellow wires to make sure I'm doing it right...

[auro]

so, this are the photos taken from testing the yellow wires connections







the engine was off, the ignition key off.

[lucky]

This is what I see.
Click once on the photo to enlarge image.

That rectifier needs cooling air. Better move that.

[Fritz]

According to the pic attached, you are measuring the wrong connector. Use its male counterpart

[Duke McDukiedook]

Yep, with ohmeters that is uaually the first check you do- probe tip touch to read zero ohms, if not ya got problems.

[lucky]

Un plug that reg/rec and move it onto that bracket.
Then pull that fues box harness out from behind and get that
fuse box in the lower left corner.

The regulator /rectifier gets very hot .You do not want it moving around or touching anything and you want it to get cooling air.

That fuse box harness can be pulled out from behind that other stuff and re routed to the lower left corner.

You can secure the fusebox with a zip tie.
See photo.
Click on the photo once for a larger image.

[TwoTired]

so, this are the photos taken from testing the yellow wires connections
the engine was off, the ignition key off.

Ok, this is progress.  Your meter is telling your that only two phases of the three phase stator output makes a connection to your probe tips.  This will reduce your 150 watt alternator to a 100 watt alternator.  And, since the bike draws 120 Watts normally, the battery will deplete in operational condition.
You found a cause for your battery troubles.  Now move on to find root cause and fix it.

That top corner terminal where the Black probe was placed is ether not making good contact with the meter's probe, there is a connection break in the wiring path to the stator, or that one of the stator outputs is open.

The yellow wires of the connector you tested go directly to the connector immediately above it on the electrical panel.  This is where your yellow stator wires connect.

Disconnect that center plug and check the male yellow terminals in the same way you checked the female yellow plug connectors.  This connector will have three yellows, a Green, a White, a B/R, and a LG/R.  The yellows, green, and white, reach into the alternator cover, via the sprocket cover.  If these yellows also show one yellow leg open, then you are looking at removal of the covers to trace the wires and look for breakage between the connector at the panel and the actual connection points to the stator at the stator.

Keep going, you'll get there.

Cheers,

[auro]

all - thanks a lot for the good tips and indications!

i will move the reg/rect in the position suggested, before it melts or worse 

before doing that, i'll try and follow the wires to this 2nd connector, and see if i can do the same test again

news as soon as possible!

 

[TwoTired]

You'll have to unwrap the harness to physically follow the wires which, imo, is wasteful effort until the pathway is proven faulty.
The wire diagram tells you exactly what connector the wires go, to make probing at "end" points, or between source and destination quite simple.

You don't dismantle an engine to note the oil level,  You use established "test points" such as the oil dipstick.  The test points for the charging system are the connectors, which are identified by the schematics/wire diagram.  And, the multimeter tests the pathways without a physical inspection along the length of the wire.

The meter's pathway is always from point  A to Point B, where point A is one probe and point B is the other probe.  Put something, anything, between those two points, and the meter tells you about it's electrical integrity.  It does this by injecting electricity at point A and noting what arrives at point B.
Probes together, it all arrives at point B.  Probes apart, and no electricity arrives at point B.  Put a suspected conductor between the probes, and it will tell you the electrical functionality of that conductor.  The Wire diagram shows you where these paths must conduct.  Even if you physically look at a wire or a connector, you will not see electricity pass through it.  The meter can tell you if it is possible to pass electricity through it.

Cheers,

[Fritz]

You'll have to unwrap the harness to physically follow the wires which, imo, is wasteful effort until the pathway is proven faulty.

Wait! I think that auro said, he'd locate the second connector and test it rather than unwrapping the generator harness

I was confused, because auro was measuring a female connector and in my memory, the connector of the generator harness was male. So I went and took a picture of what resides under my left side cover.

Auro's measurements were taken where the rectifier connects the "electrical plate harness" - the lowermost connector in my pic.
The alternator connects to the one in the middle, so he should take a measurement here first.
Then we know if the problem is located in the 'electrical plate harness' or further down.

Cheers
Carsten

[Fritz]

all - thanks a lot for the good tips and indications!

i will move the reg/rect in the position suggested, before it melts or worse 

before doing that, i'll try and follow the wires to this 2nd connector, and see if i can do the same test again

news as soon as possible!

 

Auro,

take your measurements at the connector shown below.

I've also added a picture of the location of my rectifier/regulator unit. It's the original location of the rectifier, so you should not need to move anything else around, like lucky proposed.

Cheers
Carsten

[auro]

Auro's measurements were taken where the rectifier connects the "electrical plate harness" - the lowermost connector in my pic.
The alternator connects to the one in the middle, so he should take a measurement here first.
Then we now if the problem is located in the 'electrical plate harness' or further down.

makes sense.

i'll give this a try and will report back, either later tonight or early next week (time this friday to sunday belongs already to my beloved  )

I've also added a picture of the location of my rectifier/regulator unit. It's the original location of the rectifier, so you should not need to move anything else around, like lucky proposed.

very good tip - thx for the photos and the suggestion, i'll move it there asap