UPS for 27" 2012 iMac?

These are the simplest things in the world to test. Make sure you have nothing open on your Mac... and pull the cord to your UPS.

I have both Cyberpower and APS units. Both work great.

/Jim

WilliamG said:

Large farva what issue did you have with your HP to lead you to blame the UPS? This to me still sounds like a solution looking for a problem...

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I had my HP Pavilion H8 Tower, monitor, cable modem and wireless router connected to my APC Back-UPS Pro 1000, which was a 1000VA (I forget what the wattage was, it was most likely a 600W). Everything ran fine until I had an outage on evening. I think it was more of a brown out than an outage, as the power came back on very shortly afterwards, within a few seconds. Everything connected to the APC Back-UPS unit stayed on once the unit kicked over to battery power, except for the tower. The my HP 2311 23" monitor stayed on, but went black, as if it lost signal, you could still see the power indicator light, also my cable modem and wireless router stayed on.... Like I said in my previous post, my opinion is based off my experience, and what I've heard. Granted, talk is talk, and anything could have happened to make the tower cut off while my other components stayed on, but it makes sense to me, that the cause of that issue was that the power supply wasn't able to run off of the power the battery inside the UPS unit produced.

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FreemanW said:

Uh, how about the Apple Store?

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Who places product on the Apple Store website, and creates descriptions for the products? Granted, there are reviews on there stating that those particular units work great for their iMacs. That's great for them. If they believe it works great, then they use it.... Again, I'll say it, I'm going on what I've heard. Therefor, I'm relaying what I know, from what I've heard and the incident that occurred in my own experience in an honest effort to possibly help people. But that seems to be such a huge no-no apparently...

flynz4 said:

These are the simplest things in the world to test. Make sure you have nothing open on your Mac... and pull the cord to your UPS.

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DO NOT FOLLOW THIS ADVICE.

A UPS requires a ground connection to function properly. If you simply pull the UPS cord out of the wall, there's a chance the floating ground will damage your connected devices. Use a wall switch or surge protector with a switch for testing.

large farva said:

Well, like I said, some Active PFC computers may run on a stepped approximation to a sine wave unit, but I've heard of many of them, while doing so, creating a humming/buzzing sound coming from the power supply. I know for a fact that the HP Pavilion H8 (model with the AMD Six-Core) will not run on a Stepped Approximation unit

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That's great and all, but we're talking about iMacs here, not HPs. Apple Care informs customers that stepped-approximation units work perfectly well with Apple computers, and they sell them on their site. They don't buzz when running on battery power (or AC power for that matter).

The true sin wave units better approximate AC power, there's no doubt about that, but you're claiming iMacs require them and Apple doesn't seem to agree.

Gizmotoy said:

DO NOT FOLLOW THIS ADVICE.

A UPS requires a ground connection to function properly. If you simply pull the UPS cord out of the wall, there's a chance the floating ground will damage your connected devices. Use a wall switch or surge protector with a switch for testing.

Click to expand...

Thanks for updating my post. You are correct. I had used a switched outlet when I tested mine... but I forgot when I gave the advice above.

In any case... testing your UPS is really easy to do... and recommended. Thanks again.

/Jim

Large farva, that is a strange computer death. I've been running a Cyberpower ups for year now, with a ton of brown-outs. In fact I had two brown-outs in the space of an hour just a few days ago. I was so thankful for my ups, which is why seeing these threads has me replying. I'd wager you just had some bad luck. Honestly, I've probably had at least 25-30 power-outages/brown-outs in the last 3.5 years of iMac ownership. Never lost an iMac yet! Just like you, this is my experience. Plus, I've not read of anyone using an iMac ever have it die due to power loss while connected to a ups.

I am sorry for your HP loss (that really is bizarre!), but it appears to me that an iMac will run on any old UPS with sufficient power.

I actually wanted an extra UPS for my house, so I shuffled things around and bought this one which arrived today:

http://www.amazon.com/CyberPower-CP...d=1361401098&sr=1-3&keywords=cyberpower+850va

I have noticed that when I disconnected the UPS, my 2012 iMac PSU no longer buzzes like it did on my old one (which wasn't AVR or pure sine wave) when the power goes out. I suppose that's the pure sine wave thing working, though again - I still don't think pure sine wave is NEEDED. In any case, that UPS seems to be working fine, and I simulated some black/brown-outs connected to a power-strip. Works just great so far.

Gizmotoy said:

A UPS requires a ground connection to function properly. If you simply pull the UPS cord out of the wall, there's a chance the floating ground will damage your connected devices. Use a wall switch or surge protector with a switch for testing.

Click to expand...

All the documentation I've read for the surge protectors and UPS's I've bought (all of them from APC) say they must be plugged directly into a power outlet. Is it truly O.K. to plug a UPS into a surge protector (with a switch) for testing? If not, I'll have to go down to the basement and flip circuit breakers until I find the right one.

By the way, dealnews reported today that Amazon dropped the price of three CyberPower PFC Sinewave UPS's:
http://dealnews.com/Cyber-Power-PFC-Sinewave-UPS-Systems-at-Amazon-From-98-free-shipping/722382.html

Verbatim Cookie said:

All the documentation I've read for the surge protectors and UPS's I've bought (all of them from APC) say they must be plugged directly into a power outlet. Is it truly O.K. to plug a UPS into a surge protector (with a switch) for testing? If not, I'll have to go down to the basement and flip circuit breakers until I find the right one.

By the way, dealnews reported today that Amazon dropped the price of three CyberPower PFC Sinewave UPS's:
http://dealnews.com/Cyber-Power-PFC-Sinewave-UPS-Systems-at-Amazon-From-98-free-shipping/722382.html

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As long as the surge protector's cord is of equal or greater gauge as the UPS', yes, it should be fine for temporary testing purposes. Just make sure the UPS is the only thing plugged into the protector, and the protector itself is connected directly to the outlet.

They just don't want you plugging the UPS into a surge protector with a thin cord that's already powering half a dozen other devices, a situation which could overload the thin cable and cause a fire.

Thanks, Gizmotoy.

If anyone's interested, in my experiment, a mid-2011 iMac showed no ill effects when the APC Back-UPS 725 it was plugged into switched to battery power. On the other hand, the iMac was just "idling," with no programs running.