Best UPS for a 2012 iMac?

[shenan1982]

Anyone have any suggestions of a good UPS for a 2012 iMac 27" ... would be nice to have enough juice to run for a bit when the power goes out. I was going to post in peripherials, but I think the best spot is in the iMac forum as it's unit specific. Thanks!

 

[Dadioh]

Anyone have any suggestions of a good UPS for a 2012 iMac 27" ... would be nice to have enough juice to run for a bit when the power goes out. I was going to post in peripherials, but I think the best spot is in the iMac forum as it's unit specific. Thanks!

The iMac power supply is Power Factor Corrected (PFC) so you should not use a UPS with simulated output (modified square wave). You want one with a true sine wave output. The Cyber Power series are quite cost effective for this feature. I use the 850W one myself since I don't need really long run time. Just graceful shutdown.

http://www.cyberpowersystems.com/products/ups-systems/adaptive-sinewave-series.html

 

[shenan1982]

The iMac power supply is Power Factor Corrected (PFC) so you should not use a UPS with simulated output (modified square wave). You want one with a true sine wave output. The Cyber Power series are quite cost effective for this feature. I use the 850W one myself since I don't need really long run time. Just graceful shutdown.

http://www.cyberpowersystems.com/products/ups-systems/adaptive-sinewave-series.html

What's the difference between that and the APC's like this:

http://www.amazon.com/APC-BE350G-UP..._3?ie=UTF8&qid=1364668738&sr=8-3&keywords=ups

 

[Dadioh]

What's the difference between that and the APC's like this:

http://www.amazon.com/APC-BE350G-UP..._3?ie=UTF8&qid=1364668738&sr=8-3&keywords=ups

Those UPS's generate an modified square wave output to "simulate" the sinewave that AC power normally delivers. The True Sinewave output is a true sinewave and not an approximation.

Gory details can be found here: http://en.wikipedia.org/wiki/Power_inverter

Because Power Factor Correction depends on a nice clean sine signal they get confused by square wave outputs. I have run an iMac off one of those APC UPS's before but when it switches to battery there is a buzzing noise coming from the iMac power supply and sometimes it just shuts down. Highly recommend you spend the little extra to get a sinewave UPS particularly if you want to run reliably on it for more than a minute or two.

 

[shenan1982]

Those UPS's generate an modified square wave output to "simulate" the sinewave that AC power normally delivers. The True Sinewave output is a true sinewave and not an approximation.

Gory details can be found here: http://en.wikipedia.org/wiki/Power_inverter

Because Power Factor Correction depends on a nice clean sine signal they get confused by square wave outputs. I have run an iMac off one of those APC UPS's before but when it switches to battery there is a buzzing noise coming from the iMac power supply and sometimes it just shuts down. Highly recommend you spend the little extra to get a sinewave UPS particularly if you want to run reliably on it for more than a minute or two.

A minute or two? I thought with one of the 2012 iMacs I'd be able to get at least 10-15 mins, no? Tho I'm more concerned about brown outs or surges than anything else.

 

[Dadioh]

A minute or two? I thought with one of the 2012 iMacs I'd be able to get at least 10-15 mins, no? Tho I'm more concerned about brown outs or surges than anything else.

What I mean is that with a non-Sine UPS you will not get reliable operation. So if you plan on running on UPS for a while, like 10 minutes or more, then get a sinewave output model. My experience has been that when I was using the cheap APC UPS it would work for a short while and then the iMac would shut down. With the pure sinewave you can run as long as the UPS allows depending on the capacity you buy. The 850W version will run my 2009 iMac 27" for over 10 minutes according to the specs. Never tried it that long.

 

[shenan1982]

What I mean is that with a non-Sine UPS you will not get reliable operation. So if you plan on running on UPS for a while, like 10 minutes or more, then get a sinewave output model. My experience has been that when I was using the cheap APC UPS it would work for a short while and then the iMac would shut down. With the pure sinewave you can run as long as the UPS allows depending on the capacity you buy. The 850W version will run my 2009 iMac 27" for over 10 minutes according to the specs. Never tried it that long.

I think I'm going to just go with one of the CP1000AVRLCD's ... Apple's website shows the iMac is just fine with the Intelligent UPSs, so I'm going to go with that. I live in California and in 3 years in this location I've only had 1 power outage. I'm more concerned with the quality of power supply, so the intelligent should be just fine, and I'll tell the computer to shut right down should the power be out for more than a minute or two.

 

[richard13]

Those UPS's generate an modified square wave output to "simulate" the sinewave that AC power normally delivers. The True Sinewave output is a true sinewave and not an approximation.

Gory details can be found here: http://en.wikipedia.org/wiki/Power_inverter

Because Power Factor Correction depends on a nice clean sine signal they get confused by square wave outputs. I have run an iMac off one of those APC UPS's before but when it switches to battery there is a buzzing noise coming from the iMac power supply and sometimes it just shuts down. Highly recommend you spend the little extra to get a sinewave UPS particularly if you want to run reliably on it for more than a minute or two.

I have always used APC UPS and never had the problems you are describing. That said, I'd be interested in something else if it were better. I am a bit concerned though at some of the language on the CyberPower web site. For the page you link to it says "Compatible with equipment using active PFC power supplies". Does this mean it's incompatible with equipment that does not have such power supplies? My UPS is for all my computer equipment, not just my iMac. So if that's the case I'll stick with something that I know works.

 

[shenan1982]

I went to Fry's and BBY and they didn't have any sine wave. The salesman at both said the AVR should work fine with 2012 imac. They're all AVR. Guess I will have to order from amazon????

 

[Dadioh]

I have always used APC UPS and never had the problems you are describing. That said, I'd be interested in something else if it were better. I am a bit concerned though at some of the language on the CyberPower web site. For the page you link to it says "Compatible with equipment using active PFC power supplies". Does this mean it's incompatible with equipment that does not have such power supplies? My UPS is for all my computer equipment, not just my iMac. So if that's the case I'll stick with something that I know works.

Pure Sine works with everything. Your AC entering the house is pure sine. So this is just an accurate reproduction of what your power supply is getting when it is running on regular power. So yes, you can anything on pure sine. The cheaper designs use a modified square wave because the electronics to do it are cheaper. If you can get pure sine for about the same price as a modified square wave I would buy pure sine. APC and Cyber Power are both good companies. I have 6 ups in the house. 3 of each brand.

 

[richard13]

Pure Sine works with everything. Your AC entering the house is pure sine. So this is just an accurate reproduction of what your power supply is getting when it is running on regular power. So yes, you can anything on pure sine. The cheaper designs use a modified square wave because the electronics to do it are cheaper. If you can get pure sine for about the same price as a modified square wave I would buy pure sine. APC and Cyber Power are both good companies. I have 6 ups in the house. 3 of each brand.

Ok, gotcha. That makes sense. One other question I had... I see some reviews that state this UPS is slow to transition to battery power (or at least slower than APC) have you noticed this? Based on yours and other people's feedback I am inclined to consider CyperPower. But I need it to do a good job of what I primarily need it for, which is to power my equipment smoothly and temporarily in the event of an outage.

 

[Dadioh]

Ok, gotcha. That makes sense. One other question I had... I see some reviews that state this UPS is slow to transition to battery power (or at least slower than APC) have you noticed this? Based on yours and other people's feedback I am inclined to consider CyperPower. But I need it to do a good job of what I primarily need it for, which is to power my equipment smoothly and temporarily in the event of an outage.

I have the 850W version

http://www.cyberpowersystems.com/products/ups-systems/adaptive-sinewave-series/CP850PFCLCD.html

Works absolutely fine on my 2009 27" i7 and I have not noticed anything about slow switch over. Not sure what that would look like? If it were slow then I guess the iMac would shut down? That doesn't happen so I guess it is OK. Seems like a well built unit and I got it for $119 Canadian with free shipping from Bestbuy.ca Not much more than I paid for my APC BackUPS ES750's.

 

[Tulani]

I am very much following up on this discussion. I have just bought the recent iMac 27". I tried to power it using this attached APC 650VA Back UPS and it would not start. Plugged it direct to the utility power socket and it sprung to life. So this pure sine wave theory is very much relevant. Maybe if users can list up the specific APC brand and part number that are compatible with this iMac?

 

[richard13]

I have the 850W version

http://www.cyberpowersystems.com/products/ups-systems/adaptive-sinewave-series/CP850PFCLCD.html

Works absolutely fine on my 2009 27" i7 and I have not noticed anything about slow switch over. Not sure what that would look like? If it were slow then I guess the iMac would shut down? That doesn't happen so I guess it is OK. Seems like a well built unit and I got it for $119 Canadian with free shipping from Bestbuy.ca Not much more than I paid for my APC BackUPS ES750's.

The one review I can specifically remember on this subject is for the 850W version on Amazon. The poster described the slow transition as "flicker". I'm taking this to mean that the switch from AC to battery is just slow enough to cause his TV to flicker but not enough to allow it to shut off.

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I am very much following up on this discussion. I have just bought the recent iMac 27". I tried to power it using this attached APC 650VA Back UPS and it would not start. Plugged it direct to the utility power socket and it sprung to life. So this pure sine wave theory is very much relevant. Maybe if users can list up the specific APC brand and part number that are compatible with this iMac?

Sure, I am using an APC ES 750 with absolutely no problems. I have my mid-2010 iMac, Time Capsule, and router on the Battery Backup side and my MBP and printer on the Surge Protection only side.

I'm looking to eventually replace this unit, possibly with the CyberPower 850W, and reuse it in another part of the house.

 

[Dadioh]

Sure, I am using an APC ES 750 with absolutely no problems. I have my mid-2010 iMac, Time Capsule, and router on the Battery Backup side and my MBP and printer on the Surge Protection only side.

I'm looking to eventually replace this unit, possibly with the CyberPower 850W, and reuse it in another part of the house.

Do you notice that the iMac power supply makes a buzzing noise when you run off battery? Evidently that is the symptom of the simulated output of the UPS into the iMac PFC power supply. It makes me wonder if something is getting stressed in the power supply as it struggles with the input voltage. I just feel more comfortable giving it a power input that is identical to the mains power.

 

[Tulani]

Do you notice that the iMac power supply makes a buzzing noise when you run off battery? Evidently that is the symptom of the simulated output of the UPS into the iMac PFC power supply. It makes me wonder if something is getting stressed in the power supply as it struggles with the input voltage. I just feel more comfortable giving it a power input that is identical to the mains power.

Hence one should just buy the pure sine wave UPS.

 

[shaee]

I have cyber power and love it. I use 1500AVR on 55" LCD , a 65" plasma and smaller one on my router. Currently Costco has one on sale, but I think it's only an 850AVR.

 

[shenan1982]

I have cyber power and love it. I use 1500AVR on 55" LCD , a 65" plasma and smaller one on my router. Currently Costco has one on sale, but I think it's only an 850AVR.

Do you happen to have their item #?

Oh, AVR, that won't work... as many have stated here. Doesn't play nice with the power supply on the new iMacs.

 

[AppleFan360]

Get the Cyberpower with pure sine wave. Enough said. I even use them on my Home Theater equipment.

http://www.amazon.com/CyberPower-CP...781&sr=8-1&keywords=cyberpower+pure+sine+wave

 

[Tulani]

Get the Cyberpower with pure sine wave. Enough said. I even use them on my Home Theater equipment.

http://www.amazon.com/CyberPower-CP...781&sr=8-1&keywords=cyberpower+pure+sine+wave

Does it also have the shutting down software?

 

[Dadioh]

Does it also have the shutting down software?

Do you mean the control for when to shut down the iMac in power failure? If so, then, yes, it uses the built in energy management features of OS X. So once you connect the UPS to the iMac by USB then you will see an extra tab in Energy Saver preference that is labeled UPS.

If you mean the ability to shut down other devices when the master shuts down, then, no, I don't think it has this feature. Personally I never use that feature anyway since I just sleep my iMac rather than shut down.

Also, Cyber Power has a "beta" control app for OS X that displays information about the UPS and some test feature. You can find it on the Cyber Power downloads page.

 

[richard13]

Do you notice that the iMac power supply makes a buzzing noise when you run off battery? Evidently that is the symptom of the simulated output of the UPS into the iMac PFC power supply. It makes me wonder if something is getting stressed in the power supply as it struggles with the input voltage. I just feel more comfortable giving it a power input that is identical to the mains power.

Ya know something? My UPS has recovered from AC outages a number of times switching to battery without fail or apparent issue. It wasn't until I tested this right now that I noticed a very slight buzzing emanating from my iMac. I had to put my ear up to the top just to hear it, and my house is exceptionally quiet. Is this the noise you are talking about? Or are you talking about something else?

 

[Dadioh]

Ya know something? My UPS has recovered from AC outages a number of times switching to battery without fail or apparent issue. It wasn't until I tested this right now that I noticed a very slight buzzing emanating from my iMac. I had to put my ear up to the top just to hear it, and my house is exceptionally quiet. Is this the noise you are talking about? Or are you talking about something else?

Yup. I hear it at the top coming out of the cooling vent. And I have pretty bad hearing according to my wife 🙂

My concern is not the audio level of the noise but rather that electronics making that sort of noise may be indicating that it is under stress. With the pure sine there is no such noise.

Seems to me that feeding the high frequency components of a square wave into components that are built to work at 60Hz may not be the best idea. I just prefer not to take the chance given that the cost differential to buy the pure sine Cyber Power units is so small. Cost of a new iMac power supply would go a long way.

But everyone needs to make their own buying decision.

 

[richard13]

Yup. I hear it at the top coming out of the cooling vent. And I have pretty bad hearing according to my wife 🙂

My concern is not the audio level of the noise but rather that electronics making that sort of noise may be indicating that it is under stress. With the pure sine there is no such noise.

Seems to me that feeding the high frequency components of a square wave into components that are built to work at 60Hz may not be the best idea. I just prefer not to take the chance given that the cost differential to buy the pure sine Cyber Power units is so small. Cost of a new iMac power supply would go a long way.

But everyone needs to make their own buying decision.

Yea, I know what you meant and I see what you are saying. I also agree that it's up to the individual. Thank you for bringing awareness to this problem and a possible solution.

Would I consider a pure sine wave UPS in the future? If all other things are the same or better, sure. But considering the short amount of time my computer is getting power in this state I'm not particularly worried.

 

[willgreene99]

I am using four of these (http://www.cyberpowersystems.com/products/ups-systems/avr-series-ups/CP1200AVR.html) I have been happy with these as they allow me to run for over 17 minutes before my power is restored. It seems that we get several outages a month which I assume is due to the many construction projects going on in the neighborhood. Since I got these for all of my iMacs, I have been able to run non-stop until the outage is over. The longest duration of an outage has been about 20 minutes which the ups was able to keep my iMacs running along with an Apple Airport Extreme and the FIOS router. I really am liking my purchase and would recommend them.