Constant voltage generators: and why they aren't much good.

When an electrical source of voltage that is fixed in value such as 27 or 36 volts (the voltage supplied by 3 or 4 - 9 volt batteries in series connection) is used to generate colloidal silver, the voltage is connected to the silver electrodes which are in the water.  A small amount of current then begins to flow.  At this point the current is generally about one quarter of one milliampere (a milliampere is a measure of current flow).  This allows some of the silver ions to be released from one electrode while hydrogen gas is formed and released from the other electrode.  As the silver is released into the water, the conductivity of the water increases, allowing more current to flow.  This in turn allows more silver ions to be sintered off the electrode.  So far so good.  But what happens very quickly is this:

The increased current flow allows the metal to be deposited into the water at a faster and faster rate as the conductivity of the water is increased by more silver being released.  This is a vicious cycle because in a very few minutes the current passes the point where small colloidal particles are generated.  Particle size is determined by many factors; one of them being current flow or more properly current density.  Once the flow exceeds this critical point, you must stop the process or risk producing large particles.  These particles are NOT colloidal.  They will sink to the bottom of the liquid and will generally not stay in suspension. Constant voltage generators cannot be left on for long without producing large particles.

If you ingest larger particles or silver salts in liquid such as silver nitrate you take the chance of acquiring a condition know as argyria  On the other hand, colloidal silver particles are so small they do not cause this condition.  They are continually being excreted in your bodily waste.  There has never been a case in which argyria has been attributed to ingestion of colloidal silver. 

Constant current generators:  and why they work so well.  

The voltage source may be the same or higher as constant voltage generators at the beginning of the operation but the similarity between constant voltage and constant current generators diverges rapidly.  As the current flow begins to increase with increased water conductivity, the "constant current" regulator begins to reduce the voltage in order to keep the current at the desired amount of flow.  With the voltage being reduced in order to keep the current constant, the silver particle size remains uniform.  As the water becomes very conductive, the voltage may be reduced to as little as 3 or 4 volts to maintain the desired current flow.  With this type circuit, one may leave the generator connected to the electrodes and not worry that "runaway" will occur.  You may leave the generator on until the strength of silver in parts per million (PPM) is reached and be assured the particle sizes are uniform and colloidal.  Of course we are speaking of practical limits here.  This is the secret of repeatable production of colloidal silver.

Constant current equals constant size particles.  A basic constant current generator can produce up to 50 PPM.  Any concentrations higher than this require the additions of stabilizers in order to prevent fallout.   However, CS made over 15 PPM will usually agglomerate so we recommend you do not make it over that strength.  Our automatic generator (SG6 Auto) with stirring motor can make up to 20 PPM without agglomeration. 

If the particles are as small as can be made and also colloidal, the water will be clear and will also show the Tyndall effect.  If they are larger, the water color will shift toward yellow because of agglomeration.  Still larger particles appear red; then green and the blue ones are the largest.  The proper color for colloidal silver water is clear.  If it is clear and has a weak Tyndall effect, the particle size is as small as can be made.  That is the best way to know you have colloidal silver water.  Make it yourself and then you will know and see what we mean!  The proof is in the clear color and the Tyndall effect.  Of course you can also test it using the Hanna PWT meter to determine the total PPM. 

With our SG6A automatic generator you just set the dial to the PPM (parts per million) desired and wait until the unit shuts off and you will have the best colloidal silver that can possibly be made.  It will always be crystal clear and have a weak Tyndall effect.  This generator also produces higher PPM per hour than most standard CS generators, so it will be finished in less time.

With any of our standard constant current generators, you can leave the unit on as long as you want (within limits) and the PPM of the silver continues to increase without any increase in silver particle size. You can produce about 3.5 PPM per hour in a pint (16 ounce) vessel.  Double the time and you double the strength, etc. If you produce CS under about 10-12 PPM, it will be clear because the particle size is as small as can be produced and reflects no color.  Over 12-15 PPM the CS will usually become pale yellow colored over a 24 hour period.  The reason for this time lag in color change is the particles are becoming more evenly dispersed in the solution.  They rearrange themselves to maintain the same distance from each other by virtue of their electrical charge.  Remember, "likes" repel each other.  Once the particles are completely and evenly dispersed, the color will be seen.  These particles reflect yellow light while clear CS will not reflect light because the particles are so small.  The yellow color comes from the fact that higher PPM CS allows some of the particles to agglomerate together to form a slightly larger particle, allowing yellow light to be reflected while absorbing all other colors.  Agglomeration means some of the silver atoms are starting to share electron rings. 

The bottom line is this: Make your CS clear and you will be getting the largest amount of individual silver particles per unit measure of water.  As an example, 1 milligram of silver dropped into 1 liter of water is equal to 1 part per million by definition.  If you could turn that 1 milligram into 1 million individual silver particles and disperse it in the water, the PPM is still 1.   However you now have many more individual pieces of silver in the water to attack bacteria and viruses.  If you could divide that 1 milligram of silver into so many pieces they barely reflected any light, then you would have the optimum amount of silver per unit measure of water.  Typically those particles are about .001 to .005 microns in diameter.  A micron is one millionth of a meter (or 26 millionths of an inch) so .001 microns is about 1/1000 of 1/1,000,000 of a meter.  Pretty small particles indeed. Our generators typically produce particle sizes ranging from .001 to .005 microns.  See our electron microscopy photos page to see proof. 

You may also observe this effect by directing a pocket laser beam or strong narrow flashlight beam through the liquid during the dispersion phase.  The beam will become more visible as the particles are evenly dispersed, allowing the light to reflect off them.  This is called the Tyndall effect.

Another factor in colloid production is the surface area of the electrodes. If one uses wire as the electrodes as most manufacturers do, the surface area is quite small. As an example, 14 gauge wire, which is what most units are sold with, has a surface area of approximately .8 square inches if it is submersed 4 inches in the water. Two wires will give approximately 1.6 square inches of wetted surface area.

Our electrodes are .25 inches wide and .013 inches thick. If they are submersed 4 inches, the total surface area will be 4.21 square inches. This is 2.5 times the wetted surface area of 14 gauge wires. Therefore the current density of 14 gauge wires will be 2.5 times higher than the electrodes we use. What this means is, the amount of silver released using our electrodes will be so spread out over the surface of the electrodes, it will be releasing at a slower pace. If the silver is released more slowly, the particles are smaller. They will also be more uniform in size because of the constant current regulator and stirring. The result is a more uniform, small particle size colloid.

If one used a constant voltage source, such as the typical box with three batteries or a machine that uses a wall transformer to provide a constant DC voltage, the silver would begin to be ripped off the wire electrodes very quickly because of the high current density which continues to increase during production. The resulting silver particles would be a non-uniform size and would be composed of small to large size particles as the current began to rise with time. The color of the water would be yellow, red, brown or muddy looking and silver sludge will begin to drop out and fall to the bottom.  The particles of silver are getting too large as the current begins to run away and rise dramatically.