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Surge/brown out protector recommendation
- Thread starter DianeK
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Which anomaly do you want to protect from? One is near zero voltage. The other anomaly is extremely high currents. No solution exists for both.
Which anomaly is a concern? What do you want to protect? Unsaved data or hardware?
Mainly want to preserve hardware - I'm pretty good about doing frequent saves while working.
Aren't both anomalies a risk? When power resumes full strength after a brownout I thought it comes back with a spike before settling down to normal. Please enlighten me.
Aren't both anomalies a risk? When power resumes full strength after a brownout I thought it comes back with a spike before settling down to normal. Please enlighten me.
Obviously not. Power on means everything is demanding power. So voltage rises slowly. That is potentially bad for motorized appliances. And ideal for electronics.
Low voltage is never harmful to electronics. But low voltage is hard on motorized appliances. So the utility must provide sufficient voltage. Or cuts off power to protect appliances such as refrigerators.
120 volt electronics, even long before the IBM PC existed, were required to withstand up to 600 volts without damage. Today, electronics are even more robust. Your concern is a rare high current (maybe once every seven years) that can cause voltage to exceed those numbers.
The output from my 120 volt UPS in battery backup mode is 200 volt square waves with a spike of up to 270 volts. The manufacturer calls that a sine wave output. That power is potentially harmful to small electric motors and power strip protectors. And ideal power to all electronics. Because electronics are so robust.
Either a transient current connects harmlessly to earth. Or that current is inside hunting for earth destructively via appliances. Once inside, nothing will stop that hunt. What does an effective protector do? Make a low impedance (ie 'less than 10 foot') connection to single point earth ground. So that protection already inside each appliance is not overwhelmed.
Facilities that cannot have damage routinely use that well proven and superior solution. That also costs less money.
Ideal voltage for any computer is so low that incandescent bulbs dim to 40% intensity. If voltage drops lower, then a computer simply powers off. No damage. How often do your lights dim to less than 40% intensity? If too often, they a UPS may be necessary. To provide time for unsaved data to be saved. UPS is temporary and 'dirty' power during a blackout. It does not claim to protect from the above and destructive transient current.
Two anomalies that require two different solutions.
Many UPS provide about 30+ minutes protection for less than $200. They sense low voltage brown outs and switch to the battery. They also have several surge/spike protected outlets.
See the following example (if you don't need/want sine wave, the equivalent is $150):
http://www.amazon.com/CyberPower-CP...TF8&qid=1377693653&sr=1-3&keywords=cyberpower
If you need longer term protection, you need larger UPSs or motor-generator systems.
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
There are different levels. Most any UPS from major brands/retailers will offer both backup power for a brief period and lightning surge protection. (e.g. APC, TrippLite, Eaton, Cyberpower, etc)
Power interruption protection isn't just about saving documents. It can cause OS corruption and total loss of data. It's very rare, especially with more modern filesystems. But with enough power interruption cycles in our lab testing, we routinely corrupt Win7/NTFS systems and have to reimage. No hardware damage, but massive headache.
Look for sinewave output. Most power supplies these days have Active PFC for higher efficiency, and sinewave UPS's work safer and more efficient with them.
Here's an example for $129.
http://www.amazon.com/CyberPower-CP...e-Mini-Tower/dp/B00429N192/ref=pd_sim_sbs_e_4
That's basic protection. And simliar products is all you'll find under $200.
AC power from wall powers your system until an under/over voltage situation is detected then it switches over to it's internal ac inverter source.
A better but more expensive option is what is called an "On-Line UPS". Your equipment runs off the internal AC inverter and battery full time. And the AC wall connection is there just to keep battery charged. There is more isolation.
An example of one of these from TrippLite
http://www.amazon.com/exec/obidos/ASIN/B000HVRQL8/ref=nosim/9927774-20?s=merchant&m=ATVPDKIKX0DER
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OP,
There is much wrong with this post.
Low voltage, brown out situation can damage computers. When the voltage drops too low, and switching regulators can output very dirty DC power to the internal components and cause damage. Power supplies at least since the ATX spec, (long after IBM PC) have a power good signal telling the mainboard that voltages are in spec. Properly designed mainboard will shutdown if it doesn't have this signal. Many modern computers companies, and I would assume Apple included, do brown-out testing.
220V input to a power supply designed for 120 only will damage it, almost instantly. Not all, but many modern power supplies are auto ranging and can do 100-240 US or EU power. All will blow if you connect to 600V.
Thanks everyone. Will start shopping.
What I had been doing up till now was when a thunderstorm was approaching I would shut down the computer and unplug it. I have been told that this isn't healthy for the computer because every time I do that apparently I am resetting the SMC. Is that true?
Also we live in an older house and everytime our air conditioner kicks in there is a momentary dimming of lights so I don't imagine that has been very good for the computer either. It is coming home from the hospital Friday after getting its graphics card and hard drive replaced so I want to have a battery backup/ surge protector in place for its homecoming.
What I had been doing up till now was when a thunderstorm was approaching I would shut down the computer and unplug it. I have been told that this isn't healthy for the computer because every time I do that apparently I am resetting the SMC. Is that true?
Also we live in an older house and everytime our air conditioner kicks in there is a momentary dimming of lights so I don't imagine that has been very good for the computer either. It is coming home from the hospital Friday after getting its graphics card and hard drive replaced so I want to have a battery backup/ surge protector in place for its homecoming.
Electronics do not work that way. But then if the poster knew how electronics worked, then he knew the original IBM PC had a power good signal. And why all older computers also must have that equivalent signal. It exists to protect data - even in a Mac.
Why do the fewer know this? Because the fewest also designed this stuff. Switching regulators never output ‘dirty’ (harmful) DC power. Brownouts never cause damage. More numbers - to separate the informed from others educated subjective reasoning and advertising.
If low voltages are destructive, then he cited specific component damaged by low voltage. He cannot and will not. Even earliest digital electronics (4000 series) operated on any voltage from 20 VDC down to -0.5. Numbers right from manufacturer datasheets:
http://www.datasheetcatalog.org/datasheets/208/108514_DS.pdf
All voltages down to zero and even slightly negative cause no damage. Where is this component damaged by a brownout? That damning question is never answered by many who only know subjectively – also called junk science reasoning.
Another design engineer describes how brownouts work:
Not die as in damage. Die as in power off. We routinely expose electronics to brownouts to learn how low voltages can drop before electronics power off ... always without damage. Because all computers must work normally even when incandescent bulbs dim to 40% intensity (more numbers). How often does your electricity brownout that much?
Destructive brownouts are how advertising creates mythical fears to promote sales. Only a minority actually know this stuff. Separate the chaff from reality. The informed say why and provide numbers. The naive will only post denials in soundbyte conclusions. No numbers is a first indication of junk science reasoning. Use those missing facts and numbers to separate fables and fears from reality.
What happens during power off? Internal voltages slowly drop to zero. IOW a power off is nothing more than a long brownout that eventually falls to zero. If brownouts are harmful to hardware, then so is a normal power off. Just another of so many reasons why brownouts do not harm electronics.
View numbers for that UPS. Destructive surges are hundreds of thousands of joules. How many joules do a UPS claim to absorb? Hundreds? Another damning number.
A UPS does not claim to protect from destructive surges. It only claims to protect from a different, smaller, and typically not destructive type of surge. Why is the UPS recommended without discussing different types of surges? If a UPS contains near zero joules, then advertising can hype that into 100% protection. The naive (who ignore numbers) would not know the difference. But people who designed this stuff know superior protection is already inside each computer. And those superior circuits require protection that is located elsewhere. Even a UPS needs to be protected.
Numbers were posted to define it. For example, ethernet ports already withstand thousands of volts without damage. Even the IBM PC was required to meet a 600 volt number. Informed consumers worry about the rare and destructive surge. That must be averted at the service entrance. And that the UPS does not discuss and does not claim to protect from. Even a UPS needs to be protected.
Superior protection typically costs tens or 100 times less money. Comes from other and more responsible companies including ABB, Siemens, Polyphaser, General Electric, Intermatic, Syscom, Leviton, Ditek, Intermatic, and Square D - to name but a few. Names that a guy would know for integrity. A Cutler-Hammer solution was selling in Lowes and Home Depot for less than $50. But again, these superior products would only be known by engineers and layman who demand hard facts and numbers. The UPS does not even claim to provide such protection. Don’t take my word for it. Read its specifications.
All computers had the equivalent of a power good signal. The electrically knowledgeable would know Power Good even existed in the original IBM PC – to protect data. UPS is also for protection of data. It does not even claim to provide that hardware protection that advertising ‘subjectively’ claims. Protection of hardware from destructive transients must be located elsewhere. So that hundreds of thousand of joules (another important number) dissipate harmlessly outside the building.
The informed has no tolerance for accusations based only in hearsay and subjective reasoning. He cannot even say what component is damaged by a brownout. Provided above is reality. With numbers that identify which poster actually knows this stuff.
For the OP: protection of hardware from transients requires a solution located when utility wires enter the building. With numbers that actually claim protection even from direct lightning strikes. And that are provided by other and more responsible companies. OP is encouraged to ask for details.
A UPS is for protection of unsaved data. A UPS does not provide hardware protection. Some of the ‘dirtiest’ power into a computer comes from a UPS in battery backup mode. No problem. Because superior protection already inside every computer makes the ‘dirtiest’ UPS irrelevant. As demonstrated by numbers.
Again, normal power for all computers is even when incandescent bulbs dim to 40% intensity.
However do not ignore that dimming. In most cases, it is a symptom of a loose wire. Something to fix but not be concerned about. In rare cases, the dimming indicates a major human safety threat.
For example, the homeowner ignored his dimming. Eventually a neutral wire inside the transformer failed. Since his earth grounds were compromised, electricity took other paths via the gas meter. Fortunately nobody was home when the house exploded.
Important is to identify which circuits do and do not dim. That will help identify the defect. It could be something so simple as to tighten one screw on one incoming wire.
Dimming does not harm any electronics. Otherwise you are suffering from damaged dishwasher, microwave, digital clocks, TV, bathroom GFCI, CFL bulbs, smoke detectors, or furnace.
Removing power does not adversely affect an SMC. SMC has a battery to provide power uninterrupted - with or without AC power. Layman can confirm that battery from Mac documentation. Another example of speculation and fear generating a bogus recommendation. Its battery should remain good for more than five years.
Surge protection can only protect from nearby, indirect lightning transients. There are limits. Unplugging is wise. Won't hurt your MAC.
Regarding AC.
Has a professional seen it? A little flicker is not unusual, actually common and can be ok. But it could also be a sign of something loose or wired incorrectly. Can't know without eyes on, first hand.
You could also see what it would cost for the professional to setup a whole house surge protector.
How old, is old? A 1950's era house with 60A service? A HardStart kit can be installed which is a big capacitor for the AC to pull from and lessen load on main service.
Again so many variables, ask a professional on this one if you want to address.
I don't know enough about the iMac's specific power supply to tell you if need it. But I still recommend it. The Cyberpower's linked above both have sine wave output, and are within your budget.
The $129 600W/1000VA should be more than enough. The iMac is not much more than a laptop with a nice big display. It's not like powering a gaming rig.
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Adding one more thing to this since I just noticed this thread. Not sure if I missed it but if you are worried about brown outs you want a surge/battery with AVR. Automatic Voltage regulation will correct both the brown outs and surges that may happen.
AVR already exists in every power supply. Put numbers to it. Voltages inside all electronics do not change - do not even flicker - when AC voltages drop. Voltages can drop so low that incandescent bulbs dim to 50% intensity. How often do your lights dim that much? Never? Then why do you need a UPS with AVR?
AVR, already inside electronic appliances, is so good that
Designers routinely do that to confirm AVR designs operate properly. A major function inside a power supply is AVR.
Even 'single chip' power supplies such as the 7805 output a constant and unflinching five volts when AC mains voltage drops by "2/3rds". Like all power supplies, even the tiniest 'single chip' supply already contains AVR. Why do you need what you already have?
Because a UPS hypes AVR, then many just 'know' they must need AVR. Advertisng (not electrical knowledge) is why so many recommend it.
Existing AVR means lights can dim to 50% intensity. How often do your lights dim that much? Never? They why do you need more AVR? You don't. Most who recommend AC power 'cures' do not even know if they (or you) need that 'cure'. Hyping AVR gets a majority to promote it rather than learn that it already exists.
Your original post asked for effective protection. Effective protection is provided by something completely different, located elsewhere, costs about $1 per protected appliances, and is essential to even protect a UPS with AVR.
Apparently you have assumed a surge (maybe thousands of volts) and a brownout (tens of volts) are same. One is potentially destructive. The other is made irrelevant by what already exists in power supplies. That UPS with AVR does not claim to protect from a potentially destructive surge. And it must be protected by the other and well proven solution.
