iMac won't turn on.

Some background: It has been extremely humid with much rain the last few days.
Had a 10 second or so power outage yesterday evening when my iMac was in shutdown mode.
My iMac is plugged into a surge suppressor outlet.
Tried turning iMac on this morning. Nothing. Tried a few more times nothing. Check surge suppressor output socket. Voltage okay. Even tried switching to another suppressor socket. Nothing. Unplugged from back of unit. Plugged in again after a few seconds. Still nothing. Decided to unplug for about a minute ( works for my cable box and router). Walla! iMac powers on.
Anybody have any idea what caused this? This is the first time this has happened in the 3 years i've had the iMac. Granted it has been super humid lately. Maybe running my A/C in this room when it is humid outside will keep this from re-occuring? Anybody else experience this?

It sounds like you may have had just enough of a power surge to mess it up (in technical terms ) Anyway, I am willing to bet in your efforts to restart the iMac, you reset the SMC - which is a good thing - and this got you up and running. To reset the SMC you power off, unplug the power cord and wait 15 seconds, reattach the power cord, wait 5 seconds then press the power button.

I might suggest a more robust power supply protector. I am very partial to Uninterruptible Power Supplies (UPS). They will supply power in an outage and can be set to shut your computer down when the battery in the UPS is low. It will also protect against surges, spikes and low current. They "clean up" the current. Surge protectors just cover - well - surges and sometimes that is not enough.

Lisa

Yes el cheapo surge protectors protect....nothing. Your problem was caused by the outage and the iMac required that SMC reset. As Lisa advises invest in a UPS.

First I had to look up SMC. So, System Management Controller (Eyes glazing over), right!. Anyway, found a similar post in June from a Doug Lassiter which Lisa commented on. Lisa, unable to give you a thumbs up at this time. i Am being told I must spread it around first. I was able to thumbs up harry. I will be buying an UPS. Thanks again. Pete

Thanks Pete now try thumbs up for Lisa!

Tried to buy CyberPower 1500VA/900W UPS from amazon and another dealer. Both said unable to ship to Hawaii. Went to Costco bought a CyberPower 1350VA/810W UPS on 8/25. Already helped for two power fluctuations a few days ago. Many Cyclones/Hurricanes around the islands this season. No direct hits (so far) but heavy, heavy rain and some wind. No power outages in my area so far, but a few power fluctuations that last less than 5 seconds, Have my Mac and my router on the UPS. Router turns off with the slightest power fluctuation and I lose my internet and TV service. Must be some kind of SMC on the router because I would have to unplug it and wait a few minutes then plug it back in and wait till it powers up. The UPS should help with that. Not sure if I should plug my printer (Epson WF-3640) into the UPS. Never had a problem with it so far.

At home, I have a UPS on my TV, DISHTV box, and surround sound speakers. I only have a Mac Air at home so it's charger and all the chargers for my various devices plus the answer machine are on the router's UPS. It is freaky sometimes as the power will go out and I won't loose the TV or my internet so it takes me a minute to realize it. But it has been well worth it. I have not had to replace any electronics since I did it. We did have a direct lightning strike about a month ago and it took out the power adapter of the router. I had to press the reset on the UPS. For as bad as the strike was - and believe me, it sounded and felt like a truck hit the side of the house, I felt lucky that was all that I lost. In the past I would have been calling insurance and replacing a lot of electronics.

As for plugging in the printer - I don't but that is only because of location. It is not close to either UPS boxes. If you can it is a good idea as most get upset if they are not powered off correctly. So unless you are in the habit of shutting your printer down regularly, it might not be a bad idea.

Not sure if your router has a reset after power failure feature but I have a power supply on one of my Windows computers at work that does. If the power goes off when the computer is on, you have to cycle the power switch on the PS to get it to reset and power on. Nice safety feature.

Lisa

Do have a reset on Pace router. Problem is it doesn't do much. I usually end up having to unplug it for a few minutes to get it it up and running. The UPS should fix that. My printer is next to my Mac. But i generally turn it off unless I will be printing something. May plug it into the UPS anyway. Also have an old VAIO desktop (Win 7) which I rarely use as I have a Win 7 laptop which i also rarely use. Seems whenever I turn them on I spend more time downloading widows updates than anything else. None of my TVs or cable boxes are on UPS. TVs no problem. Cable box occasionally need to unplug for a minute or so for it to reset. Never ever had electronics damaged from lightening as electrical storms are extremely rare in Hawaii. Mainly heavy rain and winds cause power fluctuations and occasional outages that usually don'y last long. Hurricanes can cause widespread outages but they rarely target Oahu, although we have had more than our share this year with another on the horizon.