On 13-9-2013 23:22, Kerry Lynn wrote: > On 9/13/13 6:38 AM, Bas Laarhoven wrote: >> On 12-9-2013 20:42, Kerry Lynn wrote: > >> <snip> > >>> The next step up from the TinyG is something like the machinekit >>> that Charles Steinkuehler has built: >>> http://www.youtube.com/watch?v=AK_OYoNOBDQ >>> http://bb-lcnc.blogspot.com/p/machinekit_16.html >>> >>> This provides you with high power FETs to control heaters, etc. >>> but is about double the cost (when you factor in the BBB) and needs >>> two power supplies (assuming you want to drive you motors with >>> something > 12V). >> >> Kerry, >> >> What (single) voltage do you want to use? The BeBoPr will accept a >> higher voltage. >> Currently the limiting factor is a 25V ceramic capacitor (C22) on the >> input of the >> step-down converter. Note that you'll also use that voltage for the >> heaters! >> >> -- Bas > > Bas, > > My mistake. I didn't look beyond the advice in the BeBoPr User Manual: > "Normally both connectors are wired to the same single 12 Volt supply." > and "The stepper motors have a separate power connector, so these can > operate at a higher voltage if required." Similarly, Figure 1 in the > manual > shows "12V system power input". So it's OK to put 24V on that connector > then? > > Thanks, -K-
Kerry, I wouldn't go higher than 18 Volts without replacing the input capacitor I mentioned. If you really want to try this out, replace C22 by two (stacked) 1210 footprint high quality MLCC X7R devices of at least 3u3 / 50V. Or wait for me to do this: The next generation of BeBoPrs will have this change included and will operate over a 11-26 Volt input range without modification. Beware that using 24 Volts instead of 12 Volts doubles the currents and quadruples the power in the attached heaters. Worst case it will destroy the heaters, best case it will blow the fuses if these are not designed to handle 24 Volts! Also make sure that the increased currents still fall within the specifications as mentioned in the manual. -- Bas ------------------------------------------------------------------------------ LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, SharePoint 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack includes Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/22/13. http://pubads.g.doubleclick.net/gampad/clk?id=64545871&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
