On Thursday, January 05, 2012 04:08:54 PM Kent A. Reed did opine: > On 1/5/2012 12:14 PM, Dave wrote: > > On 1/5/2012 11:29 AM, Kent A. Reed wrote: > >> On 1/5/2012 11:07 AM, Dave wrote: > >>> On 1/5/2012 8:45 AM, andy pugh wrote: > >>>> On 5 January 2012 13:41, Edward Bernard<yankeelena2...@yahoo.com> wrote: > >>>>> How do you deal with cooling issues having all that gear in one > >>>>> enclosure? > >>>> > >>>> I don't know yet. > >>>> The actual servo drives will be external (and near the motors) > >>>> though, so the only heat in there should be from the low-power > >>>> motherboard. > >>> > >>> If the surrounding environment is not too hostile, the easiest way > >>> is to blow air through the box - like a PC. The MW525 does not > >>> require a fan so if you create a breeze across > >>> the heat sink it should be cooled sufficiently in even a hot > >>> environment. If everything is in a sealed box the only alternative > >>> is to blow air across the components inside the box and make sure > >>> the box is large enough to become warm yet dissipate the heat > >>> into the cooler surrounding air. A MW525 system throws off about > >>> 20 watts of heat. > >>> > >>> I recently bought some of these to help keep dust and dirt out of a > >>> PC enclosure in dirty environment. Along with a good 120 mm fan, > >>> something like this would be useful in some industrial environments > >>> to ventilate a cabinet with filtered air. > >>> http://www.tigerdirect.com/applications/searchtools/item-details.asp > >>> ?EdpNo=5554585&SRCCODE=WEBLET03ORDER&cm_mmc=Email-_-WebletMain-_-WEB > >>> LET03ORDER-_-Deals > >>> > >>> The Intel bios has a display that will show you the CPU core > >>> temperature so you can get an idea of how efficiently your > >>> enclosure is keeping your PC boards cool. > >>> > >>> Dave > >> > >> Gentle persons: > >> > >> Watercooling is the cats meow in high-end gaming systems. My local > >> Microcenter has a whole aisle devoted to aftermarket add-ons like > >> pumps, heat exchangers, tubing in disco colors, etc., (with or > >> without the attendant lowrider lighting!). > >> > >> Apart from our natural conservatism, is there any reason y'all with > >> big systems aren't watercooling within a sealed box, piping the heat > >> to an external radiator? > >> > >> Regards, > >> Kent > > > > It really isn't just a CPU cooling issue. Usually the entire > > enclosure needs to be cooled. The cheap industrial way to cool a > > cabinet is to use a Exair type vortex compressed air powered cooler. > > They are relatively cheap, and bulletproof, but they eat a lot of > > compressed air. But if you have a lot of compressed air available, > > then that can be a good solution. > > I wasn't thinking just in terms of CPU cooling, Dave. With the parts > available, one can rig up almost anything, which has always been a theme > of this forum. Sure the shrink-wrapped retail components are expensive, > but that's because it's being sold to folks with more money than sense > (I've seen guys drop $5K on a custom gaming system). It can be done more > cheaply. > > The point for me was, you folks were talking about problems cooling a > box in a dirty environment. To me that says use heat exchangers. If you > don't like liquid-to-air heat exchange, use air-to-air heat exchange. > > From the days I started building experimental lab equipment, my > personal choice always has been to try not to generate more heat than I > can conduct away to ambient. These days the drive toward ubiquitous > mobile devices is solving the problem on the computer side but it's > still an issue on the motor-drive side. > > Regards, > Kent
And likely to remain so unless somebody comes up with a whole new technology whose switching losses are 10% of what we have today. In my case, 28 volt supply, times 2.37 amps=66 watts circulating between the driver and motor. I'd estimate the motor is converting 40 watts of that to heat from i2r losses while the driver is using 20 in switching time losses with the other 6 watts being wasted in the semiconductors on resistances, commonly down in the milliohm range these days. There probably is not a heck of a lot we can do about the motors eddy current and i2r losses and that is today, the almost veto proof majority. Even better iron could help, but could we then afford the motor? Good question IMO. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> New York now leads the world's great cities in the number of people around whom you shouldn't make a sudden move. -- David Letterman ------------------------------------------------------------------------------ Ridiculously easy VDI. With Citrix VDI-in-a-Box, you don't need a complex infrastructure or vast IT resources to deliver seamless, secure access to virtual desktops. With this all-in-one solution, easily deploy virtual desktops for less than the cost of PCs and save 60% on VDI infrastructure costs. Try it free! http://p.sf.net/sfu/Citrix-VDIinabox _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
