After a recent power outage, I decided it would be a good idea to buy a UPS (Uninterruptible Power Supply) to protect my Mac plus and its hard disk which are both attached to a Kensington System Saver Fan. I want to make sure that the Hard Drive will not suffer a head-crash from a power-outage. It is a 153 Mb SCSI hard disk from IBM, inside of an HD20SC case. The system saver is surge-protected, apparently. Most UPSes are also surge-protected. I've heard that it is dangerous to daisy-chain surge protectors. Is there any safe way to hook up the system saver, with hard disk and computer attached through the ports on it, to a surge-protected UPS? If not, are there any non-surge-protected UPSes? I have not yet decided on which UPS I should buy.
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Mac System Saver Fan with Surge-Protected UPS
- Thread starter drybones99
- Start date
It is not dangerous to hook up power surge protectors one after the other.
But the System Saver being as old as it is, would be worthless for protection now. Surge protectors are like bullet proof vests, they more times they get hit, the weaker they become until they are useless. In most cases, Surge Protectors last for about 8 years (5 to 10 years range), and that depends on how often they are hit with surges.
Just because your surge protector is old and possibly useless, does not mean you should throw it away. You can rebuild them with a "recap" like one does with a logic board or other Mac Board. The part that does the protection in the surge protector is a "Thyresistor." (sic.) They look like large Blue Capacitors and they are in part capacitors, but they have a property of shunting electricity in another direction (to ground) if there is an over voltage condition (power surge). All you have to do is replace the Thyresistors; there are usually 4 to 6 of them in a power surge protector. And you should get the exact ones (or ones with the exact rating) that were in the surge protector.
I'm not saying what you should do, I'm just saying what can be done and what I did in the past. There are YouTube videos out there that can show you how it is done, and companies out there that will rebuild your Surge Protector as well. You just need to dig deep on your google searches.
But the System Saver being as old as it is, would be worthless for protection now. Surge protectors are like bullet proof vests, they more times they get hit, the weaker they become until they are useless. In most cases, Surge Protectors last for about 8 years (5 to 10 years range), and that depends on how often they are hit with surges.
Just because your surge protector is old and possibly useless, does not mean you should throw it away. You can rebuild them with a "recap" like one does with a logic board or other Mac Board. The part that does the protection in the surge protector is a "Thyresistor." (sic.) They look like large Blue Capacitors and they are in part capacitors, but they have a property of shunting electricity in another direction (to ground) if there is an over voltage condition (power surge). All you have to do is replace the Thyresistors; there are usually 4 to 6 of them in a power surge protector. And you should get the exact ones (or ones with the exact rating) that were in the surge protector.
I'm not saying what you should do, I'm just saying what can be done and what I did in the past. There are YouTube videos out there that can show you how it is done, and companies out there that will rebuild your Surge Protector as well. You just need to dig deep on your google searches.
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Well after a recent power outage and losing my refridgerator (with surge protector and fuses on both inner boards) Surge protectors either dont work or are not 100% effective. Also neither fuse on the boards were blown, but all the caps were. Even after cap replacement I am ordering new boards as the boards are coated in some varnish which makes it tough to do any real trace and part testing.
A surge protector does not even claim assumed protection. Something completely different (also called a surge protector) means protection even from direct lightning strikes. Two completely different items with a same name is how scams are promoted. Technical details (ie numbers) are always necessary.
BTW, that 'varnish' is called conformal coating.
Daisy chaining any power strips is dangerous. If in doubt, ask a fire marshal. Some years ago, a local dog kennel burned down killing some 20 dogs because they daisy chained (non-protector) power strips. Power strip protectors are even more dangerous.
Another urban myth is power loss causing disk head crash. Disk drive hardware learns about power off long after power is removed. Residual power in a drive safety shuts down a drive. Disk drives always worked this way even when heads were moved by motor oil.
UPS is temporary and 'dirty' power so that unsaved data can be saved. It is, for all practical purposes, not surge protection. In fact UPS power may be so dirty as to be problematic for appliances such as refrigerators. Otherwise someone posted a specification number that said otherwise.
Daisy chained power strips are dangerous. Important feature in any power strip is its 15 amp circuit breaker (and a UL listing). All power off is sudden (unexpected) to disk drives. Hardware protection is best done by something completely different, also called a surge protector, that costs about $1 per protected appliance.
BTW power strip protectors do not use thyristors. Power strip protectors cannot be repaired (and remain safe).
I'm going to assume that a System Saver counts as a power strip, since it has two power outlets on it, one of which has a Hard Disk hooked up. A UPS is usually a power strip, so does that mean that hooking up the System Saver to the UPS is dangerous? If so, is there any safe way to protect the power on the Mac so it will continue running if the power goes out?
Power outage does not threaten any hardware or any saved data. UPS is to protect unsaved data. Nothing more.
First define each anomaly. Different anomalies are addressed by completely different devices. A UPS is temporary power when voltage decreases massively or drops to zero. Voltage can drop so low that incandescent bulbs dim to 40% intensity. UPS is for voltages that cause even dimmer bulbs. How often does that happen?
Protector is for a massive current that is either connects to earth BEFORE entering a building. Then that current creates a near zero voltage. Or current is all but invited inside to hunt for earth destructively via appliances (and UPS). Then it creates a massive voltage.
Something completely different - also called a protector - is adjacent to appliances. it will magically 'block' or 'absorb' that energy. How does its 2 cm part 'block' what three kilometers of sky could not? It cannot. How does its hundreds of joules absorb a transient that is hundreds of thousands of joules. It does not.
Three completely different and unrelated devices are discussed. 1) UPS box is for a blackout - only to protect unsaved data (and eliminate a reboot delay). 2) Properly earthed 'whole house' protector so that a large transient current (ie lightning) only creates a near zero voltage - and no appliance damage. 3) Magic power strip protector somehow does what even its specification numbers say does not. Three different items - all for different anomalies.
Mac already contain robust hardware protection. Anything on its power cord is already done better inside a Mac. Your concern is that large transient current that may overwhelm superior protection inside your Mac. BTW, that threat typically exists about once every seven years. Another relevant number.
Meanwhile, daisy chaining power strips is a fire threat.
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If power outages don't cause data problems, then what causes a head-crash? Also, are you saying that I shouldn't plug the system saver into a power strip? The surge protection on the system saver probably doesn't work, but it still counts as a power strip, since it also supplies power to the external hard disk. Does this mean that plugging the system saver into a surge-protected power strip is just as dangerous as plugging it into a UPS? Is there any safe way I can get surge protection on the system saver, since the old surge protection probably doesn't work?
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Why believe power loss causes head crashes? I am not saying this. Disk drive manufacturers said this even before PCs existed. Power loss does not cause head crashes - except when knowledge comes from hearsay and wild speculation. All power offs (intentional or unexpected) are same to disk drive hardware. No disk drive is told that power will be removed. All disk drives learn about a power outage when voltage starts dropping.
Either you have a power strip (protector or non-protector type). Or you have a UPS. I have no idea what a 'system saver' is. However if I want to manipulate the naive, then that subjective expression is a good start. If it really 'saves a system', then you have numbers (specifications) that define each 'saving' function. Any knowledge from subjective reasoning (ie Listerene kills germs) is best suspect as a scam. Either it is a power strip or it is a UPS. Two completely different devices that do completely different tasks. Which is it?
Which surge do you want to protect from? A surge on a USB port is caused by too much current (ie more than a half amp). A surge that is reported by the motherboard is a low voltage. A surge that is power restoration is a slowly increasing voltage. The term 'surge' is a vague and subjective expression. Also undefined by technical definition. Even a brownout is marketed as a surge. Some surge protectors are for protecting from a missing safety ground. One might sell a surge protector to protect from moon dust - although I have never seen that one advertised.
Assume you want to protect from a surge called lightning. Nothing inside your building protects from that. Damage due to direct lightning strikes is traceable to human failure. Some numbers. That surge is maybe hundreds of thousands of joules. How many joules does your 'system saver' claim to absorb? Hundreds? How does that system saver protection from a surge that is hundreds of thousands of joules? That is the point. They are not marketing it to consumers who always demand spec numbers.
No useful soundbyte answers exist. Most surges are made irrelevant by robust protection already inside every household appliance. Many who recommend will forget to mention that best and existing protection. Your concern is a rare surge (ie lightning) that can overwhelm that robust protection. Lightning must be connected to earth BEFORE entering a building. Failure to install that solution is a classic example of damage directly traceable to a human mistake. For over 100 years, this type protection has been routine in any facility that cannot have damage. That 'whole house' solution should also be installed in your location for about $1 per protected appliance. Protect from a potentially destructive 'surge' that may occur once every seven years.
How many discussed that seven years or any other above numbers? So again, which anomaly do you want to protect from? Floating ground, harmonics, frequency variation, open neutral, EMI/EMC/RFI, ground loop, brownout, spikes, a massive longitudinal mode current, high voltage, power factor, etc. Nothing protects from all. No useful soundbyte answer exists. An anomaly must be defined before it an be averted or solved.
Either you have a power strip (protector or non-protector type). Or you have a UPS. I have no idea what a 'system saver' is. However if I want to manipulate the naive, then that subjective expression is a good start. If it really 'saves a system', then you have numbers (specifications) that define each 'saving' function. Any knowledge from subjective reasoning (ie Listerene kills germs) is best suspect as a scam. Either it is a power strip or it is a UPS. Two completely different devices that do completely different tasks. Which is it?
Which surge do you want to protect from? A surge on a USB port is caused by too much current (ie more than a half amp). A surge that is reported by the motherboard is a low voltage. A surge that is power restoration is a slowly increasing voltage. The term 'surge' is a vague and subjective expression. Also undefined by technical definition. Even a brownout is marketed as a surge. Some surge protectors are for protecting from a missing safety ground. One might sell a surge protector to protect from moon dust - although I have never seen that one advertised.
Assume you want to protect from a surge called lightning. Nothing inside your building protects from that. Damage due to direct lightning strikes is traceable to human failure. Some numbers. That surge is maybe hundreds of thousands of joules. How many joules does your 'system saver' claim to absorb? Hundreds? How does that system saver protection from a surge that is hundreds of thousands of joules? That is the point. They are not marketing it to consumers who always demand spec numbers.
No useful soundbyte answers exist. Most surges are made irrelevant by robust protection already inside every household appliance. Many who recommend will forget to mention that best and existing protection. Your concern is a rare surge (ie lightning) that can overwhelm that robust protection. Lightning must be connected to earth BEFORE entering a building. Failure to install that solution is a classic example of damage directly traceable to a human mistake. For over 100 years, this type protection has been routine in any facility that cannot have damage. That 'whole house' solution should also be installed in your location for about $1 per protected appliance. Protect from a potentially destructive 'surge' that may occur once every seven years.
How many discussed that seven years or any other above numbers? So again, which anomaly do you want to protect from? Floating ground, harmonics, frequency variation, open neutral, EMI/EMC/RFI, ground loop, brownout, spikes, a massive longitudinal mode current, high voltage, power factor, etc. Nothing protects from all. No useful soundbyte answer exists. An anomaly must be defined before it an be averted or solved.
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For Westom and others unfamiliar, a system saver is a product marketed by Kensington under that name or perhaps a generic clone. They were marketed towards users of popular convection cooled personal computers, such as the Macintosh and Apple IIgs. These devices fit onto or under the computer and provided one or more cooling fans to augment the sometimes inadequate convection cooling. The idea was they would prolong the life of the system, hence the name "System Saver". They generally supplied power to the computer's power inlet and had surge suppressor circuitry inside, sometimes with extra receptacles for peripherals, and sometimes with front mounted power switches.
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