On 12/10/2013 11:58 AM, andy pugh wrote: > On 21 October 2013 18:21, Les Newell <les.new...@fastmail.co.uk> wrote: >> A trick to get around this is to use a 24V transformer to buck the mains >> down to 216V. Add the voltage doubler after that and your DC is spot on. > You seem to understand transforners :-) > > I am wondering what I can do with this one, that I found in a skip. > > Ideally I would like a 100V isolated supply, just to be a bit less > scary when messing about with servo motors. > (Rectified UK mains is 300V + ) > > This is the label on top: > https://drive.google.com/file/d/0BxjJW1-T6n7Cd2FrOWV5R3dRZnFhV2xrV0F3OHp3UW05X2NF/edit?usp=sharing >
That could work. The bottom two bars with the numbers under them represent the Primary windings and the associated taps. The top two bars represent the secondary windings. The "Verbdg" is the connections needed to make to get the desired voltage out of the secondary when applying voltage to the primary. So for instance, if you connect terminals 20 and 26, and 23 and 28 together and apply 220 volts to those two nodes (incoming power). And connect 37 to 39 and 36 to 38 (wiring the secondary coils in parallel), then you will have 110 VAC power available at terminals 37 and 36. To further lower the secondary voltage you may be able to fully parallel the primary by connecting 20-25 and 24 to 28, but there may be some reason why that cannot be done. The diagram does not show that. You could try it, but I'd put a circuit breaker in each primary winding connection (you will need two) just in case there is a problem doing that, then power up the transformer with no load and put a clamp on ammeter on each primary winding to make sure you don't have some circulating currents. The breakers are a "just in case" so the transformer doesn't melt down in case that is an incorrect connection. Having some circuit breakers on the primary feed is also a good idea in case this transformer was discarded due to failure. Safety glasses are advised. :-) Dave ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
