The geometry and the power supply voltage of your Colloidal Silver generator setup determine what resistor value should be used for the process. Since distilled water is a resistor, increasing the distance between the two electrodes means the resistance between the two electrodes increases proportionately. For example, in the case of my generators, the simplest and least expensive one uses only 9 V. The electrodes are quite close together. With a suitable current limiting resistor, it takes 2 to 3 hours for the accumulation of ions in the water to reach the level necessary to reduce the water's resistance to the point where the maximum current flows. The maximum current will be determined by the value of the series resistor. This resistor is in series with the power source and electrodes. The value of the resistor determining the maximum current is determined by the maximum value of current you desire. For example, let's say you build a set up which uses a 48 V DC supply. Using 48 V allows you to space the electrodes as far apart as the container opening allows and still be able to build up to maximum current in a reasonable length of time. 48 V DC is the maximum voltage that may be legally used in an application where the user could accidentally come into direct contact with this level of voltage. It is used in telephone systems. To determine the value of the current limiting resistor that you need divide the voltage you are using by the amperage desired. For example:
48 V divided by .0005 or 500 ĶA equals 96,000 ohms. 100,000 ohms would be a standard value and would be available at your local radio shack. Resistors are also specified as to the amount of power they can dissipate as heat. We are still talking about very little power here so the smallest resistor, one-quarter watt, will do. RadioShack supplies these impacts of five for $.99. If you had only 24 V as a supply, a 50,000 ohm, also a standard value, would work.