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Thread ID: 90974	2008-06-22 02:48:00	Surge protectors	jwil1 (65)	Press F1

Post ID	Timestamp	Content	User
681043	2008-06-22 23:22:00	Hi JWi To answer your questions, repeating the information I wrote in an thread sometime ago might be helpful . 1 . SPIKES and SURGES are temporary increases in voltage . A Spike lasts less than three billionths, (3 nanoseconds) of a second . A Surge lasts three billionths of a second or more . 2 . Most Surge Protectors available in New Zealand use METAL OXIDE VARISTORS, (MOV'S) . These are great but are not bulletproof and will break down after a while . These do not absorb the Spikes or Surges but divert them to ground . 3 . Surge Protectors are not created equal . All MOV's look like a round component, (normally blue), with wires attached . This does not indicate the switching speed, maximum voltage before breakdown etc . 4 . Cheap ones use a single MOV while more expensive ones use a more than one . 5 . The more expensive Surge Protectors also use TOROIDAL CHOKES . These are coils of wire around a magnetic former . Their purpose is to condition the power supply thereby feeding a more constant voltage to your gear . 6 . The Manufacturers Insurance is a good indication of the confidence in his product . Don't buy one without it . 7 . Whilst lightning and power cuts are sources of Surges and Spikes, they tend to be in the extreme . Domestic heavy appliances, such as ovens, washing machines etc switching on and off are another source . Make no bones about it . These are doing your gear harm too but more slowly . 8 . The more expensive ones also incorporate a backup FUSE . This is not a thermal cutout or a piece of wire . They use a RESISTOR . This burns out if the MOV's are unable to complete the job, thereby saving anything connected to the Surge Protector . The Resistor is monitored by LED/S thereby giving a good indication of protection . 9 . The more expensive ones also have more than one plug outlet . This allows you to protect more than one piece of equipment, ie a computer, printer, modem etc . 10 . The more expensive Surge Protectors also protect your computer gear from Surges and Spikes on the telephone wire . 11 . Do they work? They certainly do . We had a branch fall across our power line . All my gear hooked to Surge Protectors survived . Stuff like a microwave oven and a cellphone charger were stuffed . Both were plugged in directly but weren't in operation a the time . The fridge threw the towel in too . Neighbors in the area were affected in a similar way . 12 . Finally, the more expensive Surge Protectors will self-sacrifice if need be . This is not a design fault but is by design . What is more expensive to replace your computer gear or the Surge Protector? That said, what Surge Protector should you buy? Answer: The most expensive one you can afford . You can't afford anything less!! That said, lets look at some of the issues because Surge Protectors are a hotly debated subject on Press F1 . hate to disappoint, but most are one shot wonders . Yes, they are but as explained above this is by design . A surge is a rise in voltage of relatively lengthy duration (milliseconds to seconds or more) and within reason they are not particularly harmful to computers because most computer power supplies can easily withstand surges of up to 15-20%, and the NZ power system does not produce many surges of any significance . This may be true but I have replaced a string of computer power supplies that can testify to how bad New Zealand's power supply actually is . In the Wellington area, our grid doesn't seem to be as reliable as it once was . I know there is a legal requirement for the power supplier but that is my general observation . It will get worse if the looming power cuts actually occur . Your right tweak'e, most of them wont do anything . They are designed to protect against surges that are so small, that they lie within the tolerances of most appliances As outlined above small surges are still damaging your sensitive equipment but more slowly . In other words, should I get one - and if so, what should I protect? Bet yah boots, yah should . As outlined above get the most expensive model/s (from a reputable Manufacturer), you can afford . Protect all your sensitive gear like computer gear, LCD tv's, stereos etc . Get one that protects the phone line input too . This will protect your phone, modem and wireless router from any nasties coming in that way too . Do not get a cheap model . These are useless . BURNZEE	Burnzee (6950)
681044	2008-06-23 00:20:00	hate to disappoint, but most are one shot wonders. Yes, they are but as explained above this is by design. most of the basic ones on the market do not do it by design. theres no fuses/cutout etc. the better ones will generally handle mulitable big hits without blowin. good example is the microwave of yours that blew. generally they have their own built in MOV's + fuse. one of my early ones i bought for more than $100, when i opened it its was nothing more than single MOV + fuse. yet my $200 one has more than a dozen MOV's + TOROIDAL CHOKES. some are simply complete rip offs. thats the catch, how do you tell without cutting the thing open and seeing how its made.	tweak'e (69)
681045	2008-06-23 04:28:00	This may be true but I have replaced a string of computer power supplies that can testify to how bad New Zealand's power supply actually is . I do a lot of power monitoring (logging voltage excursions and spikes) and I do not find NZ's power supply to be bad at all . However, although it comes in relatively clean, users tend to mangle it on site . Go back to the supply transformer and it is usually ok . Modern computer power supplies are not all that flash and I suspect they are built to a price in anticipation of a service life of only 3-5 years . Electrolytic caps that dry out and overheated solder joints on wire-wound resistors are big killers . I have an ancient Compaq power supply taken from a 386 that is still doing sterling service in my P166 machine . it must be at least 12-13 years old and runs all day every day . As outlined above small surges are still damaging your sensitive equipment but more slowly . It is relatively rare for incremental damage to occur to electronic equipment, it usually survives or dies, there is rarely a halfway house . Putting it another way, they are either OK or dead, there is no real halfway option . Cheers Billy 8-{)	Billy T (70)
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