url: http://escribe.com/health/thesilverlist/m63486.html Re: CS>160V current regulated system - Mike M From: Date: Wed, 15 Oct 2003 06:53:41
> Mike, I appreciate all them fine words, but if the truth be known, > it was just dumb luck. See what I said? Honesty and integrity. This proves you earned it. Searching the database is not easy. You are only allowed one word of three letters or more. Try searching for Bob Lee or Tai-Pan. You have to be tough and resourceful to find anything. More proof. I could go on, but we need to start using this information. In a reply to Ken, I said I thought there was a circuit in the LM334 datasheet that showed how to make a high voltage constant current source. There are two circuits shown that would work, but they use a high voltage FET that might be difficult to locate. The LM334 is in the source, and the current can be taken from the source or the drain. So there's actually four different ways to do it. I also said in another post that Steve uses an LM334. Obviously I was wrong! That post seems to have vanished in the Sympatico server problems, but if it ever shows up, remember my mistake. You can also use a shunt voltage regulator on the base of a transistor and set the current with a resistor in the emitter. As with the FET versions, you can use NPN or PNP transistors, and take the current from the emitter or the collector. If you take it from the emitter, the output current will include the bias current for the voltage regulator, so it won't be quite as stable. So it's better to use the collector. If you want to use the NPN version, you may run into a problem. It will place the high voltage directly on the anode of the cs generator, and the cathode will also show low resistance to high voltage as the conductance increases. This presents a serious shock hazard in the event of a spill if you plan to get the 160V directly from the AC line without using an isolation transformer. This is the method I use, and I don't recommend it to others. If you use this method, it is far better to go to a PNP transistor and drive the cell from the collector. The cathode is grounded, so the voltage that is exposed to the operator is fairly low soon after you apply current. I just had a spill. You don't even have time to think what you are doing when it happens. Fortunately, this method minimized the hazard, and I wasn't shocked in the mad flurry to try to contain the water. A far safer method is to use transformer isolation. A 110VAC isolation transformer may be very expensive and difficult to find. You can also use two step-down transformers back-to-back as Steve recommends. However, this is expensive, and has no short-circuit protection. The transformers will burn out if there is no fuse in the primary. The approach I recommend uses a 24V doorbell transformer. It is designed to provide protection in the event of a short-circuit. The transformer has high leakage inductance, so it current limits exactly the same way as a neon sign transformer. But the output voltage is 24V instead of 24,000 Volts. The doorbell transformer is fairly expensive, so putting two back-to-back would double the cost. However, two simple voltage doublers will give 130VDC which is more than adequate. You can find more information on my web page: http://www3.sympatico.ca/add.automation/misc/130vdc.htm BTW: Bruce, did you know you name doesn't show up in your posts in the archive? It may also not show up in the email version. Now that you are becoming well known for your contributions, you might want to see if you can get your name to appear. Best Wishes, Mike Monett -- The silver-list is a moderated forum for discussion of colloidal silver. Instructions for unsubscribing may be found at: http://silverlist.org To post, address your message to: [email protected] Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <[email protected]>
