In the first part of this post, I detailed how a failed UPS/surge suppressor unit cost me $900: $700 in repair bills for a printer and $200 for a replacement surge suppressor. This is one of the most expensive technology lessons I’ve learned in 25+ years of computer ownership. In the process, I’ve learned that surge suppression falls very neatly into two categories: stuff that works worse over time, and stuff that works every time. It turns out that the kind of products for sale in Fry’s, Best Buy, and other consumer outlets are uniformly of the first kind, and often provide little protection when they are needed most.
My evolution in power conditioning started with cheap $9 power strips to give me more outlets, and the $20 “upgraded” ones that claimed some surge suppression. Later this grew to spending $50-70 for a “name brand” surge suppressor with fancy packaging and lots of impressive sounding language on the package. Having never spend that much on a power strip (which did no computing, and offered no functions), I thought I was set. Later I realized that I needed power protection to shut down in an orderly fashion, and so, upgraded to UPS’s in the $120-$140 range. Now I had battery backup so that even a power outage was no concern.
The problem is two-fold. The low end of surge suppression relies on two technologies: metal-oxide varistors (MOV’s) and shunting voltage spikes to the ground wire. The MOV’s work by absorbing voltage surges. Left over voltage is taken from the “hot” wire, and put on the ground wire so it can go to the earth ground in our houses. When MOV’s absorb too much voltage, they degrade internally, and never recover their initial capacity. Over time, they provide less and less protection. Normally, voltage flows from the hot wire, through our equipment, and then is returned on the neutral wire. The ground wire is used as a reference by all the electronics connected to the circuit. When high-voltages are placed on the ground wire, all the electronics see that voltage. Modern electronics all have some over-voltage protection on the ground wire, but this is never meant for the extremely high over-voltage that occurs in a power surge. This combination of factors means that power strips relying on MOV’s and shunting over-voltages to the ground wire offer little meaningful protection. You can read about this here, here, here, and here.
This is so problematic that the US government decided to provide guidance for internal government agencies so that they would purchase surge suppression that works. You can read all about that here. After you read through all the specs, the protection that we want is UL 1449, class 1, grade A, mode 1 protection with UL 1283 power filtering. This provides the proper level of protection for computers, printers, audio/visual equipment (TV’s, disc players, amps, etc). Surge protectors that meet these specifications will stop 6000V, 3000A surges at least 1000x in a row., letting only 300V through to our electronics. They do not degrade over time. These specification have been in place since 1997, so this is not new technology or information.
If you spend time researching power products on-line, you will find that most companies use marketing language to obscure what is really inside the power strip. A handful of quality companies like Furman, Surge-X, and others produce power products that are fully certified, and will work reliably over the long haul. Even many very large, very successful A/V power companies that have filled local electronics store shelves do not meet these certification, or make products where only some of them meet the necessary standard. If the product doesn’t clearly say that it supports UL 1449, class 1, grade A, mode 1, then you can be assured it doesn’t. The few products that do are quite proud of their accomplishment. Note that merely supporting UL 1449 is NOT enough – this means that something less than Class 1, Grade A, Mode 1 was achievable in the lab. These are the products we don’t want protecting our sensitive gear. You want to see that it will protect against one thousand 6000V/3000W surges, allowing only 300V or less through the protected equipment – that is what UL 1449 Class 1, Grade A, Mode 1 protection offers.
The bottom line is that if you can’t find the test results and formal certification documents for the surge suppressor you are looking for, you are NOT getting effective protection for the switching mode power supplies that are inside all our computer and A/V gear. I ultimately ended up selecting a Furman PL-Plus C so that it would fit in a rack with my music and computer gear. Other solutions exist in power strip form. For Furman gear, you want power solutions that contain their “SMP” technology – this is the marketing name they give to the circuitry that passes the stringent tests our gear requires for effective protection.
If you haven’t had a $900 lesson yet, do spend the $135-$200 required to get reliable, repeatable, non-degrading protection for your expensive electronics. I know the purchase is not exciting, and seems expensive for something that looks like a power strip, but negligence on this point can be quite costly.