Hi Lester, The DigiSpeed-GX board contains an isolated 5V to 15V dc/dc converter. It accepts a PWM signal and converts it to an isolated DC control voltage suitable for Asian DC motor controllers, and VFDs.
http://homanndesigns.com/store/index.php?main_page=product_info&cPath=1&products_id=21 Cheers, Peter. Lester Caine wrote: > Kirk Wallace wrote: >> On Wed, 2007-12-26 at 21:07 +0000, Lester Caine wrote: >>> Kirk Wallace wrote: >>>> On Wed, 2007-12-26 at 17:22 +0000, Lester Caine wrote: >>>>> Geert De Pecker wrote: >>>>>> I probably wrongly assumed that the voltage should come from the KBIC >> ... snip >>>> How much adjustment will the potentiometer give? Thanks. >>> http://cnc4pc.com/Tech_Docs/C11G_&_SIEG_X3_Electrical%20storybook.pdf >>> Check out page 7. >>> The thing to remember here is that the motor control pot on the Asian mills >>> is >>> at mains potential, so you need a totally isolated supply to drive that bit >>> of >>> the circuit. The boards I've played with a have a reasonable range on the >>> pot, >>> but I've only dropped to +9V from about 11V did not check how much further >>> it >>> would go. >>> >>> The NEW boards from cnc4pc don't have the +12V requirement on board, so a >>> +5V >>> to +12V module may be required. The on board 12V relay has been replaced >>> with >>> a 5V one so the whole board just runs off 5V now. >> Thanks for the information. Does that mean there is a high common mode >> voltage (AC or DC) on the two pins next to the DC converter? Is the >> motor controller like the speed controllers for universal motors, or Do >> you have any keywords to search on the type of motor controller this is? > > YES - basically controllers that only have a control pot on the machine are > likely not to be isolated from the main supply, and that is the reason this > little isolated control was provided. Controllers that actually have a 0 to > 10V DC input are more than likely not to require additional isolation as the > controls are already earthed (and in which case the isolated +12 can be > dropped altogether - just provide an earthed +12V). It is just the motor > controllers that do not provide an 'official' DC control voltage that need > care. > -- ------------------------------------------------------------------ Web: www.homanndesigns.com email: [EMAIL PROTECTED] Phone: +61 421 601 665 www.homanndesigns.com/ModIO.html - Modbus Interface Unit www.homanndesigns.com/DigiSpeedDeal.html - DC Spindle control www.homanndesigns.com/TurboTaig.html - Taig Mill Upgrade board ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
