2012/1/12 andy pugh <bodge...@gmail.com>: > On 12 January 2012 18:14, Viesturs Lācis <viesturs.la...@gmail.com> wrote: > >>> I was meaning a 12 to 12 (or 12 to 15) one, like >>> http://uk.rs-online.com/web/p/dc-dc-converters/6727408/ >>> >>> That gives the IRAMS board an isolated 15V supply, >> >> Thanks for the link! > > I have a feeling that that might not have a large enough current > capacity, though. I just found my proto circuit, and it has a > transformer on it, and I probably did that for a reason.
The manual says: Quiscent VCC supply current: typical = 1.6, max = 2.3 mA Do I understand that this is how much current does logics consume with 15VDC? In that case one for each chip should be totally fine, because that dc-dc converter has 200 mA output. >> Oh yes, I really would like to do that. >> Unfortunately I do not have much of a choice to get those motors >> running. So it is just one more case, where I will have to learn >> things the hard way. > > With large capacitors at 300VDC the hard way can be very hard indeed. > You might not get the chance to learn from mistakes. Do You mean risk of high voltage and even higher power electrical shock here? > Re your question about a 1:1 transformer, I think you probably want a > 2:1 anyway, as rectified mains will give you >300V and your motors are > specced for 160V. Am I missing something? Where do You see 160V? Here is motor data (from the first email of this thread): Motor type: T3-0130-60-560 Winding number: 01-00111 Rated Speed: 6000 min^-1 DC Bus Voltage: 560 V Nominal AC Voltage: 330 V Rated Motor Voltage: 309 V Rated Torque: 1,00 Nm Rated AC Current: 1,40 A Stall Torque: 1,30 Nm Stall AC Current: 1,67 A Peak Torque: 5,2 Nm Peak Current: 7,2 A Max. Speed: 12000 min^-1 EMF Constant: 47,0 V/1000 Torque Constant: 0,78 Nm/A Terminal Resistance: 12,7 Ω Terminal Inductance: 21,5 mH Number of poles: 6 El. Time Constant: 1,7 ms Mech. Time Constant: 2,4 ms Thermal Time Constant: 30 min Rotor Inertia: 0,65 kg*cm^2 If motors were meant for 160V, I would already had purchased GraniteDevices drives weeks ago... Viesturs ------------------------------------------------------------------------------ RSA(R) Conference 2012 Mar 27 - Feb 2 Save $400 by Jan. 27 Register now! http://p.sf.net/sfu/rsa-sfdev2dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
