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motoddrob

motoddrob

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Fitted a new battery and checked the RR output after having the stator off to do the starter clutch.
Voltage said 13.3 which was the battery voltage.
At revs it didn't increase so thought I'd better check the alternator as it had been removed.
Ohms reading were the same between the 3 phases and checking with the motor running at idle
Each combination showed 15v~ and at revs
It jumps to 50v~.
There is a 25a fuse between the RR output wire and battery.
Voltage at fuse input 15
Voltage at fuse output 15
Voltage at ring terminal to battery 15, connect to battery+ and it drops back to 13.3.
The RR seems to be reading high at 15v. Prior to fitting the new battery the RR had a steady reading at revs of
14.3- 14.5. It's a brand new RR that's done 800 kays.
WTF is going on!!
 
ah yes but what type of RR? Wassel? I discovered the one I had was crap, straight out of the box, although not fitted to a Laverda.
CLEM
 
The reg has to be connected up in the system for checking it, surely. It senses battery voltage etc. Your alternator volts sound fine. If the battery volts don't change it does sound like the rr is faulty, just as likely almost new as any other time. Make sure all your earths and other connections are good.
 
Morning Lee, well it is in my world!,
The weird thing is the RR is putting out 15v and as soon as I connect it to the battery+ it drops to 13.3 which is the battery voltage.
before changing the battery it was working perfectly. Don't have the original battery to put back in to try it.
Earth is good and there are only 3 connections between the RR and the battery+, fuse in, fuse out and the ring terminal to battery. Well 4 actually as there is a spade connection in line wrapperd in shrink wrap.
RR earth attached to the ally plate top left, earth wire to battery top right plus all the earths for the relays. Red wire to battery+ showing the 25a fuse.
 

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Nah the battery was going flat sitting on the bench over a 2 week period. Was replaced under warranty. The old RR was only putting out 13.7~ at revs is why I replaced it. Just wired in the old RR and it's working though still showing a low voltage.
 
Open circuit alternator windings run at over 80Vac, that is about 200V peak to peak and will test the interwinding insulation integrity ie if you must, do not do it for more than a few seconds. RR negative connection to negative on the battery, else you ask for trouble. A dropping RR connect reconnect to me is a battery taking a charge, IR losses. Where is the RR sense wire connected Rob. j
 
Morning John, the alternator is working fine, checked the output firstly by ohms between a,b a,c b,c and all 3 readings were the same.
Next did the same in AC setting with motor running and each combo showed 15v and at revs jumped to 50v. GPZ250 alternator.
The old RR was only putting out 13.7v thinking it was too low I replaced it with one Red sent me. That was putting out 14.3v about right for the lithium battery I believe. So I fitted the new battery and now the RR isn't putting out. The meter is only showing battery volts 13.3 either at idle or at revs. Reconnected the old RR and it was putting out 13.7v so I have come to the conclusion that the new RR is buggered.
The RR negative I'll take back to the battery but current location is pretty good, ie, attached to an ally plate that is connected to the battery via a 3mm wire.

"'Where is the RR sense wire connected Rob." not sure what you mean
There are 5 wires on the RR, 3 alt, wires, output that goes to battery+ via a inline 25a fuse and the negative.
To me I'm pretty sure the RR is fucked as the old one does put out a charge even if output is low at 13.7.
Started the bike again yesterday and checked and still no output from the RR.
I did put the meter between the output wire and battery neg and it showed 15v and as soon as I touched it to battery + it dropped to 13.3 which is battery voltage. Not sure if that was the right thing to do.
Is there a way of checking the RR? I'm very much electrically challenged, you way too clever for me.
Thanks John
 
Understood you have checked the alternator 3 phase output, the measuring instrument, dependent on design will read RMS or True RMS a considerable difference in certain waveforms being measured, in this case it ought to be close to sine wave and non true RMS meter will give a fair reading as such. Having said that, as i read and reread your postings, has the characteristics of a phase not present, ND wound alternators are very robust, cannot recall a failed one yet, most from GPZ and ZZR 250's used source. BTW DC resistance measurement of field windings is not a best indicator of condition, ie a shorted turn in a winding will have near identical DC resistance reading as a normal winding ( low current output due to circulating current in the shorted turn ).

Possible/rare one branch of the 6 pulse rectifier inside the RR has gone open, then am not certain what brand model you have for the RR? The usual suspect very reliable SH530 from kwaka doner engines is 6 wire ie Brown or Green wire is the sense wire discussed at length in other recent topic. Rare are internal sense wire for RR, there are ND in that form, cannot recall having one in stock over the years, rather than keep on typing, as demands allow indicate what RR you have installed and or photo. j
**** Given both RR are close in output DCv, then i would look for an intermittent open circuit or even shorted yellow wire ( one of three ) from the stator proper to the RR, careful visual, including drawing out the section in the tunnel to under the starter motor. HTH
 
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Hi John,,
Pretty sure the Alt. is working fine as the original RR [SH530 and from a ZZR rather than the GPZ as previously stated] Red supplied with the Alt up grade back in 2011 was putting out a charge [13.7 at revs] compared with the new one Red supplied, no markings and only 5 wires didn't show any output across the battery terminals.
Previously it would put out 14.5~ and of late it was showing 13.7 hence replacing it. The new one started out showing 14.3 and I went for a 800km ride and on return I pulled the battery to return for replacement as it was loosing charge over a 2 week period while sitting on the bench.
So fitted new battery and no output from the RR. Wired in the old RR and I was getting 13.7 again. My simple deduction is that the RR must be faulty. If it was the Alt. wouldn't I get the same/similar reading from both RRs.
As stated I know fuck all about electrics.
 
as a bystander looking on, as useful as it may be...grin. Has the characteristics of a failed phase. Used a HV powerscope in the day ( 20+ years ago ) when i had 13.8V no matter what i tried, swapped RR made no difference. Was able to see the failed phase waveform compared to the other phases. Like all faults it appears to not make sense, though it does, in particular when the reason or reasons is located. In this case it is more a matter of 3 phase current not being available, all phases have to be working to achieve 14,2-14,4 nominal loaded output from the RR. Suppose a third RR could be installed to make more certain, easy things first.
Click to expand...

BTW i recall on top of Mt Hotham your 180 making a hell of a racket, lucky i had ball ended allen wrench to reach around the magnetic flywheel to secure the flapping stator plate...cold it was too.... you and alternators....bad combo...grin. j
Click to expand...
 
Thanks for reminding me of that time on top of Mt Hotham, yes it was bloody cold. Standard set-up back then.
So what your saying is it looks like it could be the Alt failing on 1 phase.
I have a brymen multi meter thats full of clever stuff, shame I don't know how to use it t it's full extent.
I was told to check the 3 phases 1st using the ohms setting and look for consistency between the 3 combinations, which they were, reading exactly the same after settling down. Next was to check the output with motor running in AC setting and each combo showed 15v at idle and 50v at revs so I assumed it was working as it should.
I was initially surprised when I saw that the RR was only putting out 13.7v at revs when it use to put out between 14.3-14.5 so figured it was buggered hence buying a new one, which worked perfectly after fitting it. only change was a new battery and starter clutch which meant the stator had been removed so the wires leading into the tunnel had been disturbed. So how do I check the Alt output is working correctly.
 
81Lav said:
Hi Rob, Just a thought, maybe the doggy battery fried the new RR?
Click to expand...
Funnily enough the more a load on the output of the RR increases, the less demand is made upon the RR, at about 20Amps output the RR is not regulating, only rectifying the poly phase alternator. Why shunt RR are very robust overall. HTH j
 
motoddrob said:
Thanks for reminding me of that time on top of Mt Hotham, yes it was bloody cold. Standard set-up back then.
So what your saying is it looks like it could be the Alt failing on 1 phase.
I have a brymen multi meter thats full of clever stuff, shame I don't know how to use it t it's full extent.
I was told to check the 3 phases 1st using the ohms setting and look for consistency between the 3 combinations, which they were, reading exactly the same after settling down. Next was to check the output with motor running in AC setting and each combo showed 15v at idle and 50v at revs so I assumed it was working as it should.
I was initially surprised when I saw that the RR was only putting out 13.7v at revs when it use to put out between 14.3-14.5 so figured it was buggered hence buying a new one, which worked perfectly after fitting it. only change was a new battery and starter clutch which meant the stator had been removed so the wires leading into the tunnel had been disturbed. So how do I check the Alt output is working correctly.
Click to expand...
you have done the basic tests, ie AC output from the stator, given there are only two major parts, stator and RR, interconnect wires, one of the more straight forward electrical system to check. Pretty much done what i can from here, matter of swap out the parts in question, try the RR on another known working engine or get an electronics person to shove a 20Vdc via an old headlight into the two of the three RR input wires, check for 14.2 to 14.4 or so volts on the output, easy to bench test a shunt regulator...HTH. j
 
The new RR is putting out zero across the battery, the old RR is behaving as it was before replacing it putting out 13.7v.
Even swapped out the battery using a spare car battery and same results so have ruled out the new battery.
So my deduction is the RR is fucked.
Bruce, the old battery was working fine if I rode the bike every day. It was when it sat idle for 2 weeks the battery would go flat.
Paul had the same problem with his. Something dodgy about the LH series SSB. The older LF series I've had one in the BM for 7 years and never fail the start.
 
Interestingly the LH14 SSB LifePo that had failed in the Triumph has held full power ever since I had it fully charged and load tested several times. The 8yo SSB in the Laverda is still going gangbusters, not that it is getting much use as the bike is just sitting there. :(
 
The poor battery gets the blame when the charging system is not working correctly, failed batteries in of themselves is well known. Simple tests like mentioned here can assist in sorting the real reason for a battery condition, even then some issues require more detailed analysis and rectification, am so witty.... well, sitting here typing it looks like it, or no....j
 
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