iMac won't start up after power outage - lost cause?

[Thrifty1]

I have used a UPS battery backup / surge protector to help protect my computers. I have no electrical background or knowledge but figured the UPS could help avoid problems from a power outage or at the very least help me preserve what I was working on. A little extra protection versus just a surge protector.

It has been effective the few times I've had a power outage. Never had a problem running off the UPS battery while shutting down safely.

I picked up a UPS (APC model I believe) for about $45 when it was on sale. Gives me about 15-20 minutes of run time on my 27" iMac.

For the original poster - I would try a power supply replacement and see if that fixes it. I believe it may cost about $110 from Apple. You have to decide if that is worth a try or not.

 

[Thrifty1]

Here is the UPS battery backup I use with my 27" iMac. Last fall it was on sale for $44.99 at Staples. Not too much more than a good surge protector. Bought one for myself and one for my son who is in a college dorm. His power just went off this past Sunday for a couple hours and he was able to safely shut down his iMac when the power went off.

A new box / tab is in your System Prefs - Energy Saver when you connect this to your iMac (USB connection). You can set various options for what you want your iMac to do when the power goes out.

 

[westom]

I have used a UPS battery backup / surge protector to help protect my computers. I have no electrical background or knowledge but figured the UPS could help avoid problems from a power outage or at the very least help me preserve what I was working on. A little extra protection versus just a surge protector.

Apple switched to PC hardware to implement more advanced features found in Intel based architectures. So computer hardware features protection from plenty of anomalies such as floating ground, reverse polarity, frequency variation, bad power factor, and more.

A UPS is only for another type of anomaly - blackout. That anomaly does not harm hardware. UPS is for software/data protection.

Of course, a UPS outputs some of the 'dirtiest' power seen in a house. UPS power can be so dirty as to be potentially harmful to motorized appliances (ie refrigerator). Industry standard protection provided by Intel based hardware means 'dirty' UPS power is also ideal power for a computer.

A phrase 'surge protector' means almost nothing without defining the anomaly. Concern is for an anomaly that might overwhelm existing protection inside computers (and other household appliances). That means a 'whole house' protector is required. This solution is completely different from a power strip protector even though both are called surge protectors. Even a UPS may need protection only possible with a properly earthed 'whole house' protector.

"Surge protector" is a vague and deceptive term that can mean almost anything. For household computers, a protector must avert damage from an excessive, short, and massive current spike. For an RV, a surge protector would avert damage from a low voltage. Two completely different devices - both called surge protectors - for two completely different anomalies.

UPS is temporary and 'dirty' power for blackouts. Fortunately a computer must be so robust as to make that 'dirtiest' power irrelevant. Frequency variation may be harmful to motorized appliances. But not to computers. Do you need another surge protector for that anomaly? Each paragraph demonstrates why so many recommend surge protectors without first learning what anomaly must be addressed and what each protector does.

Also be concerned for another anomaly created by some plug-in protectors. Fire. APC (due to new management) announced many products are so dangerous as to be removed immediately. Some power strip protectors can create new threats if a 'whole house' protector is not properly earthed. Useful recommendations define the anomaly, say why it is a solution, and includes numbers.

Many may be learning of these threats for the first time. Risk of fire or compromising protection already inside a computer are a concern if using some power strip protectors. This should create plenty of curiosity and questions.

 

[Thrifty1]

Westom - you seem to have great electrical knowledge. How do you feel about whole house surge protectors?

I had considered installing the Eaton CHSPT2ULTRA for about $100 to provide surge protection at the electrical panel. Do you feel these products are beneficial?

 

[westom]

Westom - you seem to have great electrical knowledge. How do you feel about whole house surge protectors?

The 'whole house' solution is the only solution always found in facilities that cannot have damage. This is the solution I was repeatedly referring to.

Some numbers. Lightning may be 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. These are available from a long list of manufacturers with better integrity - including Cutler-Hammer. For others, these Cutler-Hammer protectors even sell in Lowes and Home Depot. Other manufacturers include Polyphaser (an industry benchmark), General Electric, Siemens, Intermatic, Ditek, Leviton. ABB, Square D, and Syscom.

That 50,000 amps defines a protector's life expectancy. A protector only connects to what actually does the protection - single point earth ground. All four words have electrical significance. Some protection systems do not even have protectors. But every effective system always has the one and most important 'system' component - earth ground.

Protectors are simple science. The 'art' is earthing. A protector is only as effective as its earth ground. Which includes other important numbers such as a low impedance (ie 'less than 10 foot') connection from each incoming utility wire (telephone, cable, AC electric, satellite dish) to that earth ground. Either directly by hardwire or via a 'whole house' protector.

A protector is only as effective as its earth ground. Protectors without that dedicated and low impedance (ie that short, no sharp bends, etc) connection to earth also do not claim to protect from the other and typically destructive surge.

 

[Thrifty1]

Westom - thank you for the reply.

I will look at some higher amps models. Square D has the HEPD80 rated up to 80,000 amps max protection and will check reviews of that model.

 

[ocean-girl]

#7
I will try all this--I'm terrified that I have a hard drive that is zapped and a lot of writing wasn't backed up.
The power in my house went out in the morning, they were doing work on the poles and the electricity and turned it off, I was asleep, then back on later, my computer had been plugged in without a surge protector!!! I'm in a panic I hope not to loose anything, meant to use a surge protector and never did.
The power cord doesn't light up (I have a macbook air) green like it usually does when you plug it in
Sounds like it worked for everyone else I'll try all this, I'm in a panic.
It was sort of a shady electric company with a strange name, not the normal central one, I hope they didn't make a mistake and send some sort of extra boost that would zap electronics or ruin computers. I am not sure why the computer would just not start up, after power comes back?!!
I have a macbook air looks like everyone else is tarlking about your imac.

 

[ApfelKuchen]

#7
I will try all this--I'm terrified that I have a hard drive that is zapped and a lot of writing wasn't backed up.
The power in my house went out in the morning, they were doing work on the poles and the electricity and turned it off, I was asleep, then back on later, my computer had been plugged in without a surge protector!!! I'm in a panic I hope not to loose anything, meant to use a surge protector and never did.
The power cord doesn't light up (I have a macbook air) green like it usually does when you plug it in
Sounds like it worked for everyone else I'll try all this, I'm in a panic.
It was sort of a shady electric company with a strange name, not the normal central one, I hope they didn't make a mistake and send some sort of extra boost that would zap electronics or ruin computers. I am not sure why the computer would just not start up, after power comes back?!!
I have a macbook air looks like everyone else is tarlking about your imac.

Right, you have a MacBook Air. That may make a big difference. It's very possible that the power surge damaged only your power adapter - the surge may never have gotten into the MacBook Air itself.

If the power adapter is damaged, then your MacBook won't charge... it may be that you have two problems - a bad power adapter and a dead battery. The first thing I'd do is try another power adapter - if the MacBook starts charging, you may have nothing more to fix.

Maybe there's more wrong with the MacBook than a dead battery... But because there is a strong possibility that the power adapter is bad, there's no way to know for sure. Don't bother with the rest of the testing/troubleshooting until after you're sure you have a working power adapter.

 

[ocean-girl]

Thanks!!

Going to try a new power cord before I panic. That came and went, too late.
Hoping the macbook is a stronger machine so hope I won't be loosing my writings......!

Even with a surge protector, you may not even know, if your computer could get zapped? I guess the older vintage macs especially which I want to collect, looking to buy a strawberry imac if I can find one. Hard to find anyone selling one?

Maybe it's truly best to turn your computers off overnight? After this I'll be on worry alert.

I had a dream the computer turned green, plugged it in and the green light went on, so dreams just can't lie, maybe with a new power cord it will turn on okay. I plugged it into the outlet and there was a little zap in the white box of the power cord, so maybe truly it is just the power cord (which is years old) and not the macbook itself.

I am guessing the genuine Apple power supply (they're about $80, I bought a generic for $25) are better, than the generic ones.

Right, you have a MacBook Air. That may make a big difference. It's very possible that the power surge damaged only your power adapter - the surge may never have gotten into the MacBook Air itself.

If the power adapter is damaged, then your MacBook won't charge... it may be that you have two problems - a bad power adapter and a dead battery. The first thing I'd do is try another power adapter - if the MacBook starts charging, you may have nothing more to fix.

Maybe there's more wrong with the MacBook than a dead battery... But because there is a strong possibility that the power adapter is bad, there's no way to know for sure. Don't bother with the rest of the testing/troubleshooting until after you're sure you have a working power adapter.