"Ian Malcolm" wrote in message ...

DANGEROUS BULL**** FROM SIMPLE SIMON. we use zinc ANODES to make the hull
cathodic to protect it.

Now consider S.S.'s idea: Hull +ve, = ANODE (and everybody knows the anode
gets eaten away). So if the end of your wire falls in the bilge water,
instead of the wire getting eaten away, you cursing the faulty circuit and
fixing it right, the steel is eten away at the nearest tiny defect in the
bilge paint and you dont know anything is wrong until you sink.

Impresssed current systems use a noble metal electrode and a carefully
controlled small voltage, electrode positive with respect to hull. Too
much causes paint failure, too little gives insufficient corrosion
protection.


Your understanding of electrical current is truly lacking.

The positive pole of a battery is where electrons congregate.
Electrons will follow a circuit to the ground side of the battery and
they will do work to get there. They will light a bulb, run a radio,
or turn a windlass.

Electrons have a NEGATIVE charge. If you make the steel hull the
positive pole the hull will have a net NEGATIVE charge. Any metal
with a negative charge will draw positive ions to it and will build
up and not waste away. It will take metal from any source and
actually plate it to the hull. This is how zinc plating of an anchor
or chain works, btw.

Therefore, sacrificial zincs aren't needed. The hull remains healthy
and expense of wiring is reduced.

I hope this helps.

S.Simon - electrically neutral

Simple Simon wrote:

The positive pole of a battery is where electrons congregate.
Electrons will follow a circuit to the ground side of the battery

No.

Are you really so stupid or are you trying to stir things up again?

Electrons have a NEGATIVE charge.

Exactly. That's why wherever they congregate you'll find the mood
very negative. The battery's negative terminal is so called because
there is a lot of negativity at it. There's a crowd of electrons
waiting for their chance to leap out and do work.

There are two models for explaining how electric circuits work.
On posits that units of positive charge travel from B+ through
your lightbulb to B-, the other that there are units of negative
charge going in the opposite direction. The two models are
equally valid. Sometimes the "units of positive charge" are
called "holes", i.e. gaps into which electrons can go.

Do you remember those puzzles which consist of X*Y-1 square bits
of plastic or wood, each of which has a unique number or letter
on it, or maybe a fragment of picture, and you can shift them
around in a X*Y frame, to get the numbers/letters/picture into
the right order/place? Well, each time you move a square left,
the hole "moves" right, etc. Electricity works the same.

If you make the steel hull the
positive pole the hull will have a net NEGATIVE charge.

No, this is wrong. And even if you had said the opposite,
that the hull would have a net POSITIVE charge, that would
also be wrong.

The hull has no charge. What you need to set up is a CIRCUIT.
Just ONE electrode is NO USE, you need TWO.

Any metal
with a negative charge will draw positive ions to it and will build
up and not waste away. It will take metal from any source and
actually plate it to the hull. This is how zinc plating of an anchor
or chain works, btw.

In solution, metal ions are positive. Different metals differ in
their eagerness to dissolve, and so if you immerse two electrodes
of different metals WHICH ARE CONNECTED TO EACH OTHER into an
electrolyte, then whichever is more eager (e.g. zinc than iron)
will emit Metal+ ions (and absorb electrons) and will be the anode.
The other will be the cathode, and will emit electrons.

If you want to discourage the hull and/or its fittings from being
an anode, you have to make it be a cathode, so you have to make
it negative. But there is no absolute positive or negative, and
choosing to wire your on-board electrical system as positive
earth or negative earth has no influence whatever. What you need
is to set up an electrolytic cell. One way to do this is with a
sacrificial anode. I suppose it may also be possible with a
non-sacrificial one, but I'm not sure. The point of sacrificial
zincs is that they automatically form a battery which "generates"
the power to let the electrons and holes flow, but the work which
is done causes the zinc to dissolve. When the "battery is empty"
the protection stops. I dare say that instead of using a zinc,
you could use a non-dissolving anode but drive it from a real
battery (of the appropriate voltage) but if you do this, then
the hull or whatever fittings you want to protect will need to
be connected to the negative terminal of that battery. The battery
WILL do work, so will need to be kept charged.

S.Simon - electrically neutral

Intellectually neutral?

Wrong! You have an anion and you have a cation.

An anion has a negative charge and a cation has a postive charge.

Anions are present at the positive terminal of a battery.
Cations are present at the negative terminal of a battery.

I rest my case.

S.Simon - neutrally charged


"Ronald Raygun" wrote in message ...
Simple Simon wrote:

The positive pole of a battery is where electrons congregate.
Electrons will follow a circuit to the ground side of the battery

No.

Are you really so stupid or are you trying to stir things up again?

Electrons have a NEGATIVE charge.

Exactly. That's why wherever they congregate you'll find the mood
very negative. The battery's negative terminal is so called because
there is a lot of negativity at it. There's a crowd of electrons
waiting for their chance to leap out and do work.

There are two models for explaining how electric circuits work.
On posits that units of positive charge travel from B+ through
your lightbulb to B-, the other that there are units of negative
charge going in the opposite direction. The two models are
equally valid. Sometimes the "units of positive charge" are
called "holes", i.e. gaps into which electrons can go.

Do you remember those puzzles which consist of X*Y-1 square bits
of plastic or wood, each of which has a unique number or letter
on it, or maybe a fragment of picture, and you can shift them
around in a X*Y frame, to get the numbers/letters/picture into
the right order/place? Well, each time you move a square left,
the hole "moves" right, etc. Electricity works the same.

If you make the steel hull the
positive pole the hull will have a net NEGATIVE charge.

No, this is wrong. And even if you had said the opposite,
that the hull would have a net POSITIVE charge, that would
also be wrong.

The hull has no charge. What you need to set up is a CIRCUIT.
Just ONE electrode is NO USE, you need TWO.

Any metal
with a negative charge will draw positive ions to it and will build
up and not waste away. It will take metal from any source and
actually plate it to the hull. This is how zinc plating of an anchor
or chain works, btw.

In solution, metal ions are positive. Different metals differ in
their eagerness to dissolve, and so if you immerse two electrodes
of different metals WHICH ARE CONNECTED TO EACH OTHER into an
electrolyte, then whichever is more eager (e.g. zinc than iron)
will emit Metal+ ions (and absorb electrons) and will be the anode.
The other will be the cathode, and will emit electrons.

If you want to discourage the hull and/or its fittings from being
an anode, you have to make it be a cathode, so you have to make
it negative. But there is no absolute positive or negative, and
choosing to wire your on-board electrical system as positive
earth or negative earth has no influence whatever. What you need
is to set up an electrolytic cell. One way to do this is with a
sacrificial anode. I suppose it may also be possible with a
non-sacrificial one, but I'm not sure. The point of sacrificial
zincs is that they automatically form a battery which "generates"
the power to let the electrons and holes flow, but the work which
is done causes the zinc to dissolve. When the "battery is empty"
the protection stops. I dare say that instead of using a zinc,
you could use a non-dissolving anode but drive it from a real
battery (of the appropriate voltage) but if you do this, then
the hull or whatever fittings you want to protect will need to
be connected to the negative terminal of that battery. The battery
WILL do work, so will need to be kept charged.

S.Simon - electrically neutral

Intellectually neutral?

Simple Simon wrote:


Your understanding of electrical current is truly lacking.

The positive pole of a battery is where electrons congregate.
*** False factoid 1 ***
Electrons will follow a circuit to the ground side of the battery
*** False factoid 2 ***
and
they will do work to get there. They will light a bulb, run a radio,
or turn a windlass.

Electrons have a NEGATIVE charge.
If you make the steel hull the
positive pole the hull will have a net NEGATIVE charge.
*** False factoid 3 ***
Any metal
with a negative charge will draw positive ions to it and will build
up and not waste away. It will take metal from any source and
actually plate it to the hull. This is how zinc plating of an anchor
or chain works, btw.

Therefore, sacrificial zincs aren't needed. The hull remains healthy
and expense of wiring is reduced.

I hope this helps.

S.Simon - electrically neutral

So let us consider current flow in seawater.

The majority current carriers are probably Na+ ions and Cl- ions.
There will also be some H+ and OH- ions.

The negative ions are attracted to the positive electrode (Anode)
The positive ions are attracted to the negative electrode (Cathode)

Now lets consider what happens when they get there.

The Na+ accepts an electron from the Cathode and is reduced to monatomic
metalic sodium. This immediatly reacts with a water molecule to form
NaOH, caustic soda (paint stripper) and monatomic hydogen. the monatomic
hydrogen is an extremely powerful reducing agent and does a great job of
removing any rust on the Cathode. (Google for "electrolytic rust
removal"). H+ ions reduce directly to monatomic hydrogen. (of course the
hydrogen cant stay monatomic for long and if there is nothing to reduce
soon pair up to form bubbles of H2 gas

The Cl- ion looses an electron to the Anode forming monatomic chlorine,
which is extremely reactive and corrosive and will attack all metals
coatings and other materials commonly used in marine applications with the
exceptions of PTFE, chlorinated rubber paint, titanium and lead. The OH-
ion looses an electron to form a hydroxyl radical which is an extremely
powerful oxidiser. You might as well immerse your boat in hydrogen
peroxide.

P.S. electrons flow out of the negative battery terminal to the Cathode in
the seawater. They flow through the water as part of ions and into the
Anode, from there they continue round the circuit and back into the
positive battery terminal to complete the circuit.

For anyone who is still unclear, Take two large clean plain iron or steel
nails or bolts, two wires, a drinking glass full of water, a battery of 6
or 12v, and a heaped teaspoon of common salt. Add the salt to the water
and stir till dissolved. Twist the wires round one end of each nail or
bolt and prop them vertically in the glass. they mustent touch and the
wires should not be in the water. Now connect the battery and you can
watch the positive nail or bolt rust before your very eyes.

Warning, do this outside as some chlorine gas may be produced and dispose
of the residuse safely. If the bolts were cadmium or zinc plated, treat it
as toxic waste. I did say to use ordinary iron or steel, not plated or
stainless.


SO THERE SIMPLE SIMON TROLL - BUSTED AGAIN
You couldnt be less electrically neutral if they hooked you up to old
smokey.

Bye for now, I've got bigger fish to fry now the fire is nice and hot.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- &
[dot]=.
*Warning* SPAM TRAP set in header, Use email address in sig. if you must.
'Stingo' Albacore #1554 - 15' Uffa Fox designed, All varnished hot moulded
wooden racing dinghy circa. 1961

"Simple Simon" wrote in
:

Wrong! You have an anion and you have a cation.

An anion has a negative charge and a cation has a postive charge.

Anions are present at the positive terminal of a battery.
Cations are present at the negative terminal of a battery.

I rest my case.



I think you pretty much rested everything years ago..

Bertie