Other Alternator test/ AC

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sierrafery said:
but just to check the alternator you can buy cheaper like this https://www.ebay.co.uk/itm/NEW-Vell...m=253788543722&_trksid=p2047675.c100005.m1851 cos all you must see is the voltage's waveform https://www.circuitspecialists.com/blog/testing-an-alternator-with-an-oscilloscope/
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Bless u for that, first link just takes me to the ebay home page I’m afraid , but second link looks interesting

Funny enough took ur advise and got my local Land Rover dealer to test all my alternator out properly with the correct equipment and was all ok

Now I’ve got all my suspension work all finished can get back to this parasitic battery drain

Know i won’t learn overnight and will be a steep learning curve

Thks again and will check out that oscilloscope some more
 
IMO on D3 and newer vehicles which have ''smart" charging systems it's enough to check the voltage without removing the bttery lead cos it should pick up the A/C component even with battery connected co without the battery's resistance the voltage might grow above some safe limit... i didnt try on a D3 myself so make some research before you do it
 
sierrafery said:
IMO on D3 and newer vehicles which have ''smart" charging systems it's enough to check the voltage without removing the bttery lead cos it should pick up the A/C component even with battery connected co without the battery's resistance the voltage might grow above some safe limit... i didnt try on a D3 myself so make some research before you do it
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Thks and indeed understand where ur coming from, , personally never disconnected the battery lead

When I had it checked out standing was 12.5VDC and with the engine running they advised me up to 15.7VDC was fine

It will currently average 14.5 VDC

I linked out the bonnet switch and then had to wait 30 x minutes before the entered sleep mode
 
If you want to rule out the alterantor for a parasitic drain you should undo it's main lead which goes to the battery over night or while you have an a-meter connected and see the drain difference when it went to sleep, if the drain drops then it's the alternator, IMO no need to spend money for an oscilloscope only for this reason, it's good to test the alternator with it if you already have one and use it for other things too like i do but IMO it doesnt worth the investment just for that
 
sierrafery said:
If you want to rule out the alterantor for a parasitic drain you should undo it's main lead which goes to the battery over night or while you have an a-meter connected and see the drain difference when it went to sleep, if the drain drops then it's the alternator, IMO no need to spend money for an oscilloscope only for this reason, it's good to test the alternator with it if you already have one and use it for other things too like i do but IMO it doesnt worth the investment just for that
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Thks, dealer tested that all out for me and ruled it out, but thks as that’s good to know

Agree and wouldn’t buy a oscilloscope if it was just for the alt

The next fuses I’m going to check are the ones with the small plastic cover on, going to remove all the covers and test them one by one

Know I can’t pull the fuses one by one as I’ll wake the system up again so will be a slow methodical test to eliminate things 100%

Plus must disconnect my other battery so I don’t get any possible false readings

Thks as I always appreciate ur expertise and extensive knowledge

21752705-F029-47E8-AC43-F08DC5C8B6FA.jpeg
 
sierrafery said:
There are more types, the automotive one is a MSO addapted for engine management troubleshooting too, most common and largely used are the digital stoage type... a rough description here:https://www.tek.com/document/online/primer/xyzs-scopes/ch2/oscilloscope-types , you have usefull links in the right coloumn to get you started
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Fantastic , thks so much as funny enough I saw two similar oscilloscopes, one a lot more expensive because it done waveform, so that link giving descriptions will be very handy ,

Learnt a little something as I’ve been doing some more reading earlier and see u can do a cyl compressor test and if I’m understanding it correctly the oscilloscope measures the current in the starter motor , if there’s a low compression in a cyl the starter motor uses less energy as it’s cycles onto that bore and therefore indicates that particular bore doesn’t match the rest , hope that sort of makes sense

Also seen this one , but alas have to use a laptop , however suppose it’s easier to see a larger screen , lol

Shame u can’t get one that works with an iPad

https://www.ebay.co.uk/itm/Hantek-6...691970?hash=item44204cfac2:g:KDUAAOSwj99aAExv
 
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sierrafery said:
yes, you can get a relative compression but you need a current clamp for that ... (no visible link in your post)


Click to expand...


https://www.ebay.co.uk/itm/Hantek-6...691970?hash=item44204cfac2:g:KDUAAOSwj99aAExv

Thks and very clever , bet u would be seriously lost not having one now

indeed also see u have to put the clamp the right way round for the direction of voltage

Kit with a clamp , https://www.ebay.co.uk/itm/6074BE-C...796271&hash=item1cb3a0d92a:g:k5UAAOSwnn1bWYH6
 
sierrafery said:
Yes, Lenz's law .... that tool from your link seems good
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always good for me to learn new things , lol

Imagine ur very well into ur electronics arnt u

Just watched this video ref that tool and an alternator test



Must admit like the fact it’s the complete kit with 2 x clamps and all the leads

Don’t think it would be a hardship using a laptop , seeing I wouldn’t be using it every day

https://www.ebay.co.uk/itm/1008C-US...817073?hash=item1ee825e771:g:mtoAAOSwX5ZbFnlc

Wonder if they could be used to test airbags safely
 
I dont see a way to test airbags with oscilloscope but i didnt even think about that... anyway in that video is shown the 100% accurate way to test an alternator which would have passed any other test with different tools, that waveform means that there is a problem within the rectifier pack so if only one juncntion doesnt close well there will be a drain through it.
 
sierrafery said:
I dont see a way to test airbags with oscilloscope but i didnt even think about that... anyway in that video is shown the 100% accurate way to test an alternator which would have passed any other test with different tools, that waveform means that there is a problem within the rectifier pack so if only one juncntion doesnt close well there will be a drain through it.
Click to expand...

Many thks and was just a passing thought ref the airbags , suppose was thinking of the bi signal an oscilloscope tests and me going off tangent as always, lol

Makes a lot more sense with that video u kindly linked

Thks
 
@sierrafery

Hi

Hope u don’t mind me asking , but been looking at current clamp meters

Wondering then if I connect it to my main battery lead via a multimeter to show me what the parasitic drain is , then using another multimeter on each fuse one by one to look which circuit is causing the issues , do u think that’s a better set up than using a cheap clamp meter plse

was just wondering what ur thoughts were plse as I know u have a vast electrical knowledge

Thks again and hope u didn’t mind me asking

B28CB3A2-41A0-48B1-BDA4-1C2A1AA37C50.jpeg
 
Hi, i dont understand your plan and seems overcomplicated, i dont get what you mean by "using another multimeter on each fuse one by one to look which circuit is causing the issues", it's enough to use a multimeter connected in series between the battery clamp and terminal(or a clamp meter on the positive lead) then when the systems went to sleep remove fusible links one by one(i mean remove, see the drop then put it back) ... if there will be a serious drop one one of the FLs at least you'll have to remove only the fuses which are on that circuit not all cos most fuses are somehow connected to the fusible links or of there' is no serious drop on FLs you'll have to remove the fuses which are not through a FL if you see what i mean, when you find it you have to check the power distribution diagram and there you are

btw how much is your battery drain with systems at sleep?
 
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