Clark Martin wrote: > Bruce Johnson wrote: >> On Apr 29, 2009, at 6:58 PM, Paul wrote: >> >>> .I had been reading about how UPS's in general don't provide >>> very good quality power in a blackout, >> That's a very odd statement to make, since when running off of battery >> UPS'es are providing as clean a power as you can get. > > If you are talking about a true UPS which outputs a sine wave that is > true. Most UPSes produce what is called a modified sine wave and it is > about as ugly as power gets.
Splitting hairs a bit, but the term 'true UPS' (aka online UPS) refers to how the power circuit is set up (http://www.pcguide.com/ref/power/ext/ups/typesOnLine-c.html), not the power output. I have a pair of APC SmartUPS units (1400 and a 1000) that are not 'true UPS' units (they are line interactive) that output a true sine wave, not the modified variety. A 'true UPS' /could/ output a modified wave, but IMO, it's unlikely that the manufacture of the unit would skimp on this due to the overall higher cost of this design. Visual aid! http://www.extremeoverclocking.com/reviews/power/Belkin_F6C1500TWRK_UPS_6.html I ran into this one when I was looking up info on the Belkin 1500VA I had just bought (was an emergency purchase, couldn't afford an APC at the time). Covering another post in the thread regarding APC units... Per APC (http://www.apc.com/solutions/display.cfm?id=0D72DB57-8963-47DA-9ADC4EB3FD07511D): "APC's Back-UPS®, Back-UPS Office®, Back-UPS Pro®, and PowerCell® all output a "stepped-approximated" sine wave when the unit is On Battery. While this kind of waveform is ideal for computers and computer-related equipment, it may not be compatible for other types of loads like motor loads. If you are using non-computer loads with one of the above-mentioned UPSs, consult the manufacturer's specifications to determine if the equipment can run off of a "stepped wave". If it can't, then it will require a UPS that outputs a pure sine wave when On Battery. APC UPS models that do output a Pure Sine Wave include: Smart-UPS®, Matrix-UPS®, and the Symmetra® Power Array®." This is why I sprung for some used SmartUPS units, I wanted real sine wave output. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed Low End Mac's G3-5 List, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com To unsubscribe from this group, send email to g3-5-list-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
