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#Post#: 100710--------------------------------------------------
Alternatr wiring confusion.
By: AlmightyBodgeKing Date: February 4, 2016, 8:50 am
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Hello again.
I am now confused over alternator wiring.
My 1969 SIIA has, as far as I know had an alternator from new.
Anyhow, I have noticed the last couple of days that the
voltmeter is sitting at 12V where it used to read 14 ish when
driving. The Ammeter is showing positive 30A ish, indicating the
battery is charging (the battery has not gone flat yet). I tried
it with a multimeter direct on the battery and it read 12.3V
with engine off and 12.3V with engine running. Indicating that
the alternator is not doing its job. But If this was the case,
why is the battery not dead. I drive in to work in the dark with
lights on and heater going full chat. I drive home from work
with lights on and the heater going full chat, surely the
battery would be dead by now if it wasn't charging.
Now I look in my books and cannot find a wiring diagram matching
what I have in the vehicle anywhere. The alternator wiring
appears to go to a large cable running along the front of the
engine bay to the battery (as I would expect from an alternator)
but also to some black boxes attached to the inner wing at the
front. What are these boxes likely to be. There is also
something that looks like it should turn, but with a locking nut
on the front, sort of 2 metal discs with something inbetween
them.
If anyone could point me to a wiring diagram suitable for my
SIIA it would be much appreciated. Or, for that matter, if
anyone could explain the system to me, that would be also very
much appreciated.
#Post#: 100711--------------------------------------------------
Re: Alternatr wiring confusion.
By: AlmightyBodgeKing Date: February 4, 2016, 11:18 am
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Right, so, I have figured out that the alternator has no
internal rectifier/regulator. So the thing with the discs is a
rectifier (probably just a load of diodes) and one of the black
boxes would be a regulator. But there are no big hefty cables
going to it so I don't know yet how it regulates, maybe it does
something with the field windings, I need to trace the wiring
and work it out.
No idea yet what the other box is, maybe just a junction box of
some sort.
Now, while driving home fr work, at one point the ammeter
dropped to zero (this has been intermittent since I got her).
But I noticed that when that happened, the charge voltage rose
to a
Much nicer 14V.
Maybe I am loosing an earth and this is causing the ammeter to
read 30A when it should, in fact, be zero. Maybe the ammeter is
faulty and when it does spring to life, it somehow stops the
regulator from producing an output.
Can anyone with an ammeter tell me what the normal current
reading is for cruising?
Sorry it's another long one.
#Post#: 100712--------------------------------------------------
Re: Alternatr wiring confusion.
By: hippydave Date: February 4, 2016, 11:20 am
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Well just in case this is the only diagram i have with an
alternator on it and not a dynamo.
[URL=
HTML http://s1208.photobucket.com/user/hippydavec/media/Wiring%20Diagram%20New_zps8rntozcj.jpg.html][IMG]http://i1208.photobucket.com/albums/cc377/hippydavec/Wiring%20Diagram%20New_zps8rntozcj.jpg[/img][/URL]
#Post#: 100713--------------------------------------------------
Re: Alternatr wiring confusion.
By: DarrenH Date: February 4, 2016, 11:35 am
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ammeter on +30 amps doesn't show the battery is charging, it
shows how much battery discharge the alternator is trying to
replace, which should be about equal to all the electrical items
you have switched on.
alternators are very much "on demand" system where the voltage
should be steady but it dynamically alters its amp output to
suit the needs
a voltmeter does show if the battery is charging (or not) as
you say if its showing 12 and a bit, its not charging.
as you say modern alternators are internally
regulated/rectified, maybe yours is a vintage external type.
#Post#: 100714--------------------------------------------------
Re: Alternatr wiring confusion.
By: AlmightyBodgeKing Date: February 4, 2016, 12:55 pm
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Thanks HippyDave, but I have that one already. I am looking for
one that shows the external regulator/rectifier setup.
DarrenH, I have no idea where the +30 amp reading is coming
from. With everything on (heater,lights,radio etc) I have
measured a total load of 9Amps. Why it would be as high as 30 I
don't know. This is why I am leaning towards a bad earth
somewhere.
#Post#: 100715--------------------------------------------------
Re: Alternatr wiring confusion.
By: DarrenH Date: February 4, 2016, 2:36 pm
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two headlights (Dipped beam) plus sidelights and tail lamps is 9
amps on its own, 10 amps on main beam. deffo something fishy
going on !
#Post#: 100718--------------------------------------------------
Re: Alternatr wiring confusion.
By: Serious Series Date: February 5, 2016, 3:04 am
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Can you post a pic of your alternator and the control boxes?
#Post#: 100720--------------------------------------------------
Re: Alternatr wiring confusion.
By: AlmightyBodgeKing Date: February 5, 2016, 1:02 pm
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I will post a pic later or tomorrow. Currently on childcare
duty.
#Post#: 100722--------------------------------------------------
Re: Alternatr wiring confusion.
By: AlmightyBodgeKing Date: February 5, 2016, 4:25 pm
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Apologies for the poor photography, best I could do with a
tourch and my phone.
[IMG]
HTML http://i651.photobucket.com/albums/uu231/AlmightyBodgeKing/Mobile%20Uploads/image_zpsm1l4jwj4.jpg[/img]
[IMG]
HTML http://i651.photobucket.com/albums/uu231/AlmightyBodgeKing/Mobile%20Uploads/image_zpskdnxekai.jpg[/img]
[IMG]
HTML http://i651.photobucket.com/albums/uu231/AlmightyBodgeKing/Mobile%20Uploads/image_zpsrq98rp4g.jpg[/img]
[IMG]
HTML http://i651.photobucket.com/albums/uu231/AlmightyBodgeKing/Mobile%20Uploads/image_zpsnpgqinjk.jpg[/img]
[IMG]
HTML http://i651.photobucket.com/albums/uu231/AlmightyBodgeKing/Mobile%20Uploads/image_zpsg3poraah.jpg[/img]
#Post#: 100723--------------------------------------------------
Re: Alternatr wiring confusion.
By: Serious Series Date: February 6, 2016, 3:37 am
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Cannot find a landrover wiring diagram like that but here is one
with similar set up except the rectifier is inside the
alternator.
[URL=
HTML http://s1359.photobucket.com/user/61Doug_Palmer/media/Landrover%20electrical/AlternatorWiringSchematic-1963Buick_zpsl3ekyj5l.jpg.html][IMG]http://i1359.photobucket.com/albums/q786/61Doug_Palmer/Landrover%20electrical/AlternatorWiringSchematic-1963Buick_zpsl3ekyj5l.jpg[/img][/URL].
How many wires exit your alternator?
For reliability fit a modern alternator.
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