Voltage regulator just so you know!

[Kendo]

Well heck. I read he had problems with the ammeter, and went down a rabbit hole of dash-related stuff. Never mind! Carry On.

[Grumblebuns]

Ken, been there, done that.

For those wanting a reference on vintage British electrical systems, I recommend this book.

"Classic British Car Electrical Systems" by Rick Astley

[dakazman]

I went looking for a schematic of the VS. Didn't find that, but found a troubleshooting guide.

  I thought we were talking about the voltage regulator.
dakazman

[Kendo]

So, Rickrolling is the answer to British electrics?

[Grumblebuns]

Hey Ken, never heard of Rickrolling, had to look it up. Didn't try it. 

[Kendo]

Sorry to inflict a bit of internet history on you. I was just amazed two such different people would have the same name. Plus, it was a silly bit of internet history.

[califkid_66]

Thanks for the troubleshooting guide Ken
Little update I checked my local Napa store and they had a voltage regulator so I bought it and when I got home first thing I did was opened it up  and it wasn’t an electronic one but mechanical I figured since it’s new and mechanical I could see the resistance and capacitor to get for my old vr but again to my surprise there no resistance or capacitor it’s wired direct you can see from the pictures so now I’m a bit confused should I use it as is should I ad a resistance and capacitor it is usually used on 70’s Chrysler did they have the resistance and capacitor in the alternator or something in between
Or is it ok without them
One more thing what is the purpose of the two bars under the vr last picture
Thanks again!

[califkid_66]

Ok now this is getting ridiculous I installed the voltage regulator did not put the cover on started the engine and the ampmeter was showing +30 amps so I figured it’s not adjusted so I adjusted it the ampmeter read ok when I reved up it went to 10+ amps but then there was smoke coming out the back so I stopped everything looks like it’s coming from the two rods under the box
I am stumped I unplugged everything I have no idea what’s going on so I’m just gonna walk out of the garage and take a breather

[califkid_66]

Used the multimeter to go around the circuit and noticed that the bracket that bolts to the fibreglass had twelve volts in it  so putting a ground on that created a short but that how the old vr  was wired
 I removed the ground from the vr
Started the car 12 v power going in the vr 12 v out going to exiter no ground no smoke stays on
But doesn’t buzz like supposed to stays on no movement at the points I manually pressed on top to simulate when battery is charged and magnet pulls points apart then checked the voltage going in 12v going to exiter nothing witch is supposed to be
Needs adjustments but doesn’t seem to want to let go
 
Then I decided to put the electronic one I had before without the ground and seems to work ok without the ground on the bracket the only thing is power going in 12v going out to exiter varies from 8v to 12 v witch doesn’t make sense to me should be on or off so I wanted to know if at 8v the alternator was generating power so I removed the battery terminal and the engine died the alternator felt hot
I put the ground back on electronic one always charging even when battery is full stays at 12v on exiter side and engine keeps running when I remove the bat terminal so it’s not doing it’s job


The new vr seems to have burnt underneath

[Grumblebuns]

Have you tried to check the voltage across the battery terminals with the car running. If the alternator and VR are functioning properly, the VR should maintain battery voltage around 14.2 volts. This is per Rick Astley's book. If it's higher, it could be the cause of the hot alternator

[califkid_66]

Yes I was checking the battery neg pos with engine on waiting to see when the alternator would turn on and to see when it would turn off like I wrote before I pressed on it to turn it off with light on to lower the battery so it would turn on but it didn’t I was below 12 volts didn’t turn on then I turned it on manually and let it run in the 13 v lights off the voltage regulator never turned off always had power at the exiter even though the battery was charged
 I would like to know what is the turn on voltage and turn off voltage cause it doesn’t seem to want to do either

[Grumblebuns]

According to Astley's book, the VR should cycle the field windings to ground between 13V (ON) and 14.2V (OFF).

[califkid_66]

Thanks I’m gonna try to see if I can adjust it with these parameters
One little question I’m looking all over can’t find the answer what are those two insulated wires under the voltage regulator I’m trying to figure out if they could be the source of my problems

[jbcollier]

Voltmeters are not set by looking at an ammeter.  You set them to the specified voltage and that’s it.  Metal covers affect the magnetic field of the regulator and, if I remember correctly, it will read about a half volt high with the cover off.

Now to your troubles.  First, is the rotor wiring in your alternator shorted out?  If it is internally shorted to ground, then you will indeed fry regulators.

Second are you hooking up the regulator correctly?  Are the terminals clearly marked?  Some regulators control the power side of rotor windings (rotor windings ground inside the alt), some the negative side (rotor windings powered from the alt and the regulator the negative side).  So check the original application of the regulator you bought and make sure it matches the rotor wiring of the Renault alt.

The long tubes under the regulator are high-current resistors.

[jbcollier]

I think you are confusing generators which also have current regulators as well as voltage regulators (and cut off relays).

Voltage regulators have normally closed points. The points are held closed by spring tension.  As the voltage rises, the magnetic field increases and, at a certain set point, it pulls the points open.  This cuts the power to the rotor windings, the alternator stops charging, the voltage falls, the magnetic field in the regulator falls, and the points close starting the cycle again.  This happens so rapidly that the alternator maintains a steady output.