Electrical Basics, More 'Homestead' than 'Survival'

AR Hammer

Deaf & Powder Burned...
Think 'Electro-Magnetic Link',

Electricity and Magnetism are forever linked in EVERYTHING we do as humans.

There is static electricity, but that does you no good, every thing you do will be magnets and conductors (Wiring)
So you don't have to worry with anything else.


LINK: http://en.wikipedia.org/wiki/Electromagnetism


Rule 1.

A MOVING magnetic field will create or 'Induce' (Induction) an electric current in any conductor (Wire) it passes through.

LINK: http://en.wikipedia.org/wiki/Electromagnetic_induction

If you make a coil of wire, put a volt meter on that coil, pass a magnet through that coil,
You will be INDUCING an electric current.

If you move the coil of wire through a magnetic field, the coil will produce an electric current,
Since the magnetic field is MOVING relative to the coil (Conductor).

LINK: http://micro.magnet.fsu.edu/electromag/java/faraday2/

You can do it either way,
Move the magnet, or move the coil, doesn't matter since the magnetic field is still MOVING relative to the conductor.

ANY electrical Production you make will be based on the electromagnetic link and INDUCTION,
(To INDUCE a current in a conductor)


Rule 2.

Stationary magnetic fields DO NOT induce current.

A magnetic field SITTING STATIC in a coil of wire WILL NOT create, or Induce, a current.
The field MUST be moving relative to the conductor.

A prime example of this is a 'Stator' in a proximity sensor.
Proximity sensors are simply a magnetic core with wire wrapped around them.

When something Ferrous (Ferrous metals, means metals that are magnetic) comes close enough to the proximity sensor, the magnetic field of the magnetic core is attracted to the ferrous component, and the magnetic field reaches out to the component...
That means the magnetic field MOVES through the coil of wire around the magnetic core at it reaches out...

Moving magnetic field through a conductor means CURRENT is produced in the stator winding,
And the proximity sensor produces a signal that something has approached it.

Again, it's basic 'Rule 1' stuff, and since the proximity sensor has no moving parts, it lives a LONG time.


Rule 3.

When a current moves though a conductor, it creates a magnetic field.
This is also the other half of the electro-magnetic link.

When you wrap a coil of wire around a metal core (to focus that magnetic field) and run a current through that wire, it will create 'Electro-Magnet'.

A high voltage wire next to a low voltage sensor wire will create a magnetic field that will often trigger the sensor (False Trigger).

You can create an electro-magnet and use that electro-magnet to create even higher voltages in field windings. That's how an alternator and wound generator works.

Rule 4.
Generators use OUTSIDE force to create energy or current flow.
A hand crank generator or small wind mills usually use fixed permanent magnets and a spinning electrical winding inside,
Or they use fixed stator windings and a spinning permanent magnet.

While most engine driven generators use an electro magnet instead of fixed magnets.

Link: Molecular Expressions: Electricity and Magnetism - Interactive Java Tutorials: Faraday's Experiment

When you take a MODERN current generator OF ANY KIND apart, you will find two things right away,
(I say 'modern' because I know some nimrod is going to pull a static generator out of his butt at any time!)

These are NOT the 'Outside' windings,
Field Windings are the 'Collectors' or 'Stator' part of the generator.

They will be on the spinning armature on a DIRECT CURRENT (DC) generator,

They will be inside the larger part of the case outside the rotor in a modern ALTERNATING CURRENT GENERATOR (Alternator for short).

Since there aren't very many DC generators out there anymore, I'm going to stick with the 'Alternator' or 'Alternating Current Generator'...


Part 1. ROTOR.

The rotor in a modern alternator is an 'Electro-Magnet, and a fairly powerful one.
The rotor has TWO contacts called 'Slip Rings', continuous, smooth metal bands that receive external current,
A fairly large winding of wire to form the 'Electro-Magnet' when current is applied,
A SOFT IRON core to focus & direct the magnetic field to 'Pole Pieces',
And 'Pedals' or 'Leaves' to create an ALTERNATING 'North' & 'South' poles when it's spun.


An actual Rotor showing Bearing Surface, Slip Rings, Pole Faces, front frame or front half of housing, and drive nose.

Link Removed




IN the case of modern alternators, that is the ROTOR,
The rotor is the magnetic Field Producing Part Of the unit,
And the outside windings that most people refer to as 'Field Windings' are the STATOR WINDINGS.


Part 2, STATOR,

The 'STATOR' is the outside windings in the case of modern 'Alternators'.

These stator windings are there for the MAGNETIC FIELD to pass through, and INDUCE a current in them.
That current is collected up by the way the windings are TERMINATED (End Terminals for each winding) and there are a few different designs...

Since the Magnetic Poles switch from North To South very quickly,
You will be getting AC, or 'Alternating Current'.
AC switches polarity very quickly from Positive to Negative as the North & South poles pass by each winding in the coil.
Since this happens the STATOR DELIVERS ALTERNATING CURRENT (Hence the name 'Alternating Generator').

Most people don't know if you tap directly into the Stator of the common car alternator, you can WELD OFF IT!
IT's capable of 220 volt, 3 phase power in it's raw form!
You can run 110 volt AC appliances directly off it when wired correctly!
We'll get to some of that later...

The 'Stator' is a series of windings off set to each other,
So one magnetic pole leaf can induce them right after another, then the polarity of the moving magnetic field changes very quickly, and the windings produce again as the polarity changes.

A VERY efficient way to produce electrical current for the home hobbies, vehicle engine, ect....



Refection from AC to DC can be done two ways,
One is the old fashioned 'Armature' with a bunch of commutator leaves with brushes contacting individual windings.
This collects all the 'Positive' pulses on one brush, all the Negative pulses on the other brush.

This was VERY inefficient.
Copper contact leaves came out of the insulating material at high speed, there was limited space on the rotor for windings so it didn't produce very much usable current.
Most 'DC' generators that rectify at the current at the armature/commutator will fly apart if you spin them very hard, and with limited collector windings, they were low output.

We'll stick with 'Alternating Current Generators' (Alternators) since they are MUCH stronger, much more efficient, take much less maintenance, and generally do a better job all the way around.

With modern Alternators, there is a 'Solid State' (no moving parts) component that makes this possible. The DIODE.


A Diode is a 'One Way' gate valve for electrical current,
Depending on how it's installed in the circuit, it will only let current pass in one direction...
By using a pair, the 'Positive' pulse of the AC is let out, then it's let back in through another diode once it does it's job.

In the average alternator, there are 6 diodes for the three sets of stator windings, one 'Positive', one 'Negative' for each winding.
(Some heavier alternators will use more than one set for each winding, so you will see them in multiples of 6 in that event)

A RECTIFIER will be a fairly large piece of usually aluminum, sometimes copper, with 'Fins' on it to cool the diodes as they work.
There will be THREE terminals for the three sets of field windings, and there will be SIX diodes set in that aluminum
AC current goes in through the field winding terminals, DC current comes OUT the rectifier common terminals.

Couldn't be more simple!

Since user 'FM1910' complained, I will wait for 'Moderator' approval or deletion of this thread before I continue,
I don't see any since in trying to educate if it's not wanted or not needed.

Well, this is the 'Survival' section,
Part of 'Survival' will be what you can do with what you find or already have.

And it was asked for by form users when I mentioned I had a library that included volumes on electronics and electrical devices.

Would be the same thing as discussions on clothings, knives, camping gear, vehicles, recipes, ect.

If it's too far off subject, then I'm sure the 'Moderators' will delete it...

I would think that being able to turn an alternator into a wind/water generator, welder, plasma cutter, EDM in a pinch would be a 'Useful Survival' tool...

I'm sure that recharging batteries would be a primary concern, although the 'Easy' way would be a simple and cheap SOLAR CELL recharger for batteries...

Not so easy to cut or weld metal off a solar cell, but you CAN weld off of charged batteries if you know what you are doing.
And basics to know what you are doing is what this tread was aimed at.

I built my own EDM/ metal 'disintegrator' for removing broken screws & pins, broken threading taps from firearms, custom porting work, ect.
Once you know the electrical basics, it's not hard to do at all.
Using EDM for barrel bore will give you HARDENED flats in the barrel rifling, which makes the barrel last MUCH longer... In the event you ever decide to make your own firearms.
(All BATFE Rules APPLY when making firearms!)

I use EDM for pin holes, screw holes, ect. for the same reason, it hardens the material around the precisely sized hole, so the pin doesn't wear away the frame material as quickly, making for a longer lived firearm (or what ever you are working on).

If one were to do any 'Custom' gun smithing work, I would think this would be a useful bit of information to have.
Custom porting work is VERY expensive for no harder than it is to do...
FN1910, This is the Survival forum on a gun-related website. The fact that there is Survival forum here indicates enough interest HERE for this thread to exist.
And the purpose of this thread on a gun forum is?

Because I asked him to post some more info :secret:

This is good info, posted in the Survival portion of the site. I think that I am not the only one here lacking knowledge in this area..I think its good infor for newbies, or people like me who haven't dabbled in 25+ years. I'm not seeing the issue :pleasantry:
Great post! A general knowledge of electricity and how it works can be invaluable in a survival situation. AR Hammer I doubt this thread will be deleted since it falls within the realm of this forum. Please continue for those that are interested in this subject.
AR Hammer...

Great job on the electrical primer...I wish i had that knowledge a few years back when a 5HP motor went south on me and it cost a lot to repair.
Still no word from the 'Management' other than to chastise me on referring (in general) to 'Fan Boys' and 'Gadget Buyers'...
No thread in specific, but I'm sure I disagreed with someone that decided to complain or disagreed with someone that is a 'Fan Boy' or 'Gadget Buyer' or one of the conspiracy guys...


If there are no more direct objections...

There are TWO basic ways to go about this,

1. You can spin magnets in coils of wire,

2. You can spin coils of wire in a magnetic field.

Spinning coils of wire in a magnetic field is difficult,
It takes a 'Commutator' to rectify the current produced,
And all those contacts & brushes cause a ton of problems,
Plus you are VERY limited on the production of current you can make because of the size restrictions on you spinning coils.

It's MUCH EASIER to spin a magnetic field (Spinning magnets, either permanent magnets or electro magnets) inside of a BUNCH of coils of wire.
Since the OUTSIDE coils are not moving, and you have a much larger space to add coils for more production OUTSIDE of the magnetic field,
This is currently the best way to do things...



1. Smaller Wire in the 'Stator' or 'Production/Collection' windings to make more VOLTAGE and increase electrical current over time (Wind Generator, Water 'Micro-Hydro' generator, ect.).
Smaller wire means more turns in the same space for the windings, and the more turns of wire, the more voltage you will create,


2. Larger wire diameter (Gauge) and you will produce LESS voltage, but more AMPERAGE in the electrical current.

This makes PERFECT sense when you apply it to the different jobs you will have for anything that produces electrical current...

Back to #1, Smaller wire making more turns or 'Loops' in each winding,
This will produce higher voltage, but less amperage,
EXACTLY what batteries need to charge!

Batteries will OVERHEAT and break down if you try and charge them too fast.
Smaller amperage and reasonable voltages is PERFECT for charging batteries,
So an alternator with the STATOR re-wound with smaller gauge wire, making more turns, produces the same 'Watts',
But in a more useful form for storage batteries to accept.

I don't have a bunch of wind where I'm at,
But the wind blows nearly every night, when the sun IS NOT shinning,
And the wind blows when the sun isn't shinning,

At night, after my batteries have been 'HIGH Charged' by the solar panels,
The wind kicks up, turns the little wind generator, and 'Finish Charges' or 'Trickle Charges' my battery sets to top them off correctly.

Anytime the sun isn't shinning in the daytime, the wind is usually blowing, so I get SOME charge from the solar panels even on overcast days,
And the wind generator provides SOME charge to go along with what even overcast solar panels will produce, and I still get charge even on an overcast day(s)...


Following up on #2,
Something like WELDING takes a very LARGE amount of current,
Large cables, lots of amperage, and a large amount of energy (Electrical or Mechanical) has to be converted to do welding...

With a vehicle alternator, you CAN weld directly off the alternator!

What you are looking to do is 'Hot Wire' the rotor to increase the magnetic field to it's maximum,
Then spin that magnetic field so it creates (Induces) the maximum current output from the STATOR windings.

You are pretty much taking the voltage regulator out of the circuit, and controlling the ROTOR (Magnetic Field) directly.

A common car alternator usually pumps somewhere between 65 and 85 amps at 12 to 24 volts.
This is MORE than enough to weld from,
Normal 'Stick Welding' voltages are usually around 16 to 20 volts at 25 to 75 amps.

If you decide to do this, then use SMALL DIAMETER welding rods! They take MUCH LESS amperage to sustain the arc with, and it will keep you from burning out the alternator right away.
You will have to take FREQUENT BREAKS to let the alternator cool down, and with small diameter rods, you will have to make more 'Passes' to get the job done,
But you CAN do welding on most anything you will encounter in an 'Emergency' situation...

We are CONSTANTLY welding stuff in, welding up cracks, ect. on our off road/trail vehicles,
And I've made hundreds of welds in the field from a common vehicle alternator...
Welds that are still holding up to this day several years later.

This same electrical generator can be used for a 'Plasma' type metal cutter,
For 'Gouging' type rods to cut metals,
And with carbon rods for metal smelting to make cast metal parts.
This is called 'Induction' smelting.


You can ALSO use two (or more) batteries to weld off of,
You welding time will be VERY limited unless you have several batteries,
But you CAN weld off as little as two 'Car' batteries when wired correctly.

Again, it's all about how the batteries are wired, how well charged they are,
And what size cables/clamps/connections you are using, but it can be done quite successfully.


Still waiting for the moderators to shut this down, so I really don't want to post up a bunch of diagrams, spend a bunch of time drawing those diagrams and posting the text if it's all going to get deleted,
So I'm still waiting for a moderator to approve continuing this thread...
If I get the 'OK' from someone on the big end, I want to show specific types of alternators, how to modify them for charging, welding, wind service, ect.

YOu can feel free to PM me any more of that info in the meantime :) I have some accounts on some of the "preparadness sites", maybe we can exchange them there, and with less scrutiny :pleasantry:

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