A UPS for my new iMac 21.5"

You're going in deep circles in your mind.

I finally installed UPSs on all my systems after having so many power failures it became intolerable. If there is one thing that proved it was that the iMac's power supplies are robust. Power quality here was awful at the time, with failures at least once a day and twice in the summer.

I wouldn't and don't run any desktop computers without them connected to a UPS. It is one of those Needed Extras when you run a desktop.

As the others have said you seem to be thinking in deeper circles than needed. Look at it like this, if you pull the wall socket out your Mac crashes, thats not good. If you have a UPS and the Mac is plugged into that UPS you pull that pull the ups plug out the wall and your Mac stays on and will shut down as and when you have decided in the power settings.

I have mine set up using a pure sinewave 1500 Smart UPS. It protects my printer, my router, my 400 watt amp and speaker set up fo the Mac, two external hard drives, and a emergency light. The power goes off I can still work on my iMac browse the web and have light at night when the street is in darkness. The power here is not great, so that UPS protects the Mac from any potential surges, and the brownouts I get. The power remains contsant and clean, and my electronics live to fight another day.

No computer really should be online without one as I see it. Knowing when you are out that if the power goes out your Mac is safe and the drive wont crash, that peace of mind is priceless. Knowing that the power supply is not being buffereted by the drop in my mains supply is great. A UPS is the right thing to use. I have one for my smart TV, satelight PVR and playstation 3 which also keeps my wireless telephone powered as well in case of a power cut (I am disabled so its important) Buy one, you wont regret it. 🙂

Sorry but you are missing the point.

1) You Can connect the iMac to the UPS with Just the Main AC cable, NO USB cable between the 2 devices (Computer and UPS) and forgo any software awareness that the UPS is in use BUT still have it Protect the system from a Power Outage so you can safely shut the system down. The UPS will BEEP Constantly when the AC power goes out warning you that it is now running on the battery backup power.

2) You can connect the main AC cable AND Run a USB cable from the computer to the UPS and OS X has Built in software to monitor the UPS and set options in the Built In OS X software to Auto shut down the computer or NOT.

3) No if you Just connect the main AC cable to the UPS there will not be ANY Monitoring of the UPS Nor will there be any options for Auto Shut Down of the system. The Shutting Down would be totall manual be whoever was using the computer at the time of a power outage. If no one was at ort near the computer then when the UPS battery ran out of power the computer would just Turn Off like you yanked the AC cable out of the wall outlet. Not a good thing.

I justy hope you maybe understand what I have posted as it seems you really have not understood anything anyone else has posted to this thread or how a UPS works.

Good Luck & Best Wishes.

I'm out of this thread. Good Bye.

ronenhaim wrote:

I understand that a UPS is connected to the iMac in 2 ways :

1. By electric Cables ( Mains Power )
2. A USB cable to receive and transmit software information .

#2 is optional and only necessary to inform the Mac that it is running on battery power. Software on the Mac in turn informs you, and can optionally shut down the Mac automatically when the battery nears depletion.

All APC UPSs that I linked above (except for the cheapest model) have this feature. Any UPS with a USB cable will probably work too. I only have experience with APC.

Simple one of 2 things:

• If you are there you can do an orderly shutdown.
• If you have set the UPS to do a shutdown after X minutes of no power the iMac will do an orderly shutdown.

That's what a UPS is for!!!!!!!!!!!!!!

when an iMac is in a Sleep Mode , And a UPS is connected , what happened if a Mains failure occurred ?

As far as the Mac is concerned, absoutely nothing.

A sleeping Mac uses about as much power as a night light. Depending on the specific model UPS you choose, it will continue to sleep, on UPS power, until the UPS battery dies. This could be eight to twelve hours.

Does the iMac need to be protected when it in a sleep mode ?

A UPS conveys at least two specific benefits: power conditioning, which addresses poor power quality (e.g surges, sags, dropouts) and backup power so as not to interrupt your work if the power disappears for brief periods of time: minutes, not hours. Most consumer grade computer UPSs are intended to keep your equipment powered long enough for you to save your work and then shut down your Mac, rather than have unsaved work disappear.

A Mac deprived of power will lose unsaved work whether it is sleeping or not. However, it is worth pointing out that most new Mac apps (such as Notes and Pages) automatically save your work so this has become less of a concern recently. Apple seems to be designing their products, both hardware and software, with a goal that the user should not have to be burdened with the tedium of periodically saving work.

As far as "protected" goes, a UPS's power conditioning holds true even for a Mac that is "shut down". The problem with most consumer electronics these days is that almost nothing has a real power switch any more - nothing to separate it from mains power, as long as it is plugged in. Therefore a Mac that is plugged in but "off" is still connected to the mains, and exposed to potential damage from nearby lightning strikes that can dissipate energy through electrical wiring. A UPS provides a degree of protection from that threat, though it by no means absolute.

Yes

As above with a side note, if you are out you want that usb connection because a UPS will not shudown your iMac without that USB cable. You set it up, leave it plugged in, leave your Mac plugged in and thats it, game over you are protected, unless you get a very close or direct lightning strike. So you can be anywhere even when your Mac is asleep and it will then go into shutdown to save itself after x amount of minutes, or however you choose in the power setttings. Your Mac needs protection ay all times and that USB cable connection is needed at all times. Hopefully you understand it all now. I think there is no more anyone can say that hasnt been said.