Guide to Power Protection
By Joshua Erdman
Many businesses put much effort to protecting their data. They perform daily backups, they keep a monthly copy of their backups off site, they even test to make sure an emergency recovery by tape will work. But good data backups is only one side of the coin to data protection in a secure environment. All computers run on electricity, it is their lifeblood and also an area that is commonly neglected.
Clean and continuous power is everything. The majority of data loss caused by unexpected power loss or crashes from 'unclean' power can be avoided if you use the right equipment.
There are 9 main power dangers. Any of which can cause crashes, data loss, signal transmission intereference, or equipment damage:
There are 3 basic types of power protection each that can protect you from a number of these power problems:
Surge suppressors range in their capability. Some take no effort to remove noise and distortion in the AC signal and just prevent large, momentary power spikes (such as lightening). Others, with advanced circuitry, can reduce line noise and distortion as well.
The biggest mistake I see with business networks is the lack of Surge Suppression. Using a Surge Suppressor is the BARE Minimum when using any piece of electronics. People mistake a simple, two dollar power strip for a surge suppressor. A power strip is typically a device that provides 6 or more plugs from one cable with little to no protection at all.
When buying a surge suppressor notice that its protection is usually rated in Joules and Volts. Joules is the amount of uncontrolled energy that a strip is capable of handling. The higher the number the better the protection. I recommend at least 600 Joules for typical office equipment (computers, printers, fax machines) and a UPS for Servers and maybe the accountant's computer. CyberGuys sells a great suppressor perfect for the office environment for cheap.
Using a power conditioner can do amazing things for your electronics. With televisions and stereos, reception and quality are improved. With computer equipment you can expect fewer crashes and equipment failure.
A typical power conditioner requires utility power to work (a standalone power conditioner does not contain batteries and thus will not work when the electricity is out). There are 2 types of power conditioners, one that conditions the signal (sometimes called a line conditioner) and the other re-creates the AC sine wave sometimes called 'Double Line Conversion'. The use of a power conditioner provides 'clean' power to your electronics.
Pay close attention to the capabilities before you purchase a power conditioner. The definition of 'Power Conditioning' from a marketing standpoint is blurry at best. Many times even though they are selling what is labeled a 'Power Conditioner', you may actually be buying a line conditioner and not the Double Line Conversion Conditioner. Any type of power conditioning is better than using a surge suppressor. Since the sine wave is cleaned there is little to no chance of your devices getting a surge.
Digital electronics (such as computers) actually run on DC power. It is the power supply in these computers that convert the AC power (120V if you are in the United States) to 12V and 5V DC for the motherboard and other computer peripherals. The power supplies usually draw their power at the peak of the AC sine wave. Since the use of computers has grown so much, all these electronics tend to distort the quality of the sine wave. This distortion can cause early wear on power supplies or even crashes on computers with more sensitive power supplies. The use of an oscilloscope can give you a quick picture of just how clean your AC power is.
A Battery Backup (A.K.A. UPS or Uninterruptible Power Supply) at the minimum is just as it says, a device that contains batteries that are continuously being charged while there is utility power. As soon as utility power is dropped, an inverter recreates AC power from the batteries to provide constant power to the devices plugged in to the UPS (provided that the batteries in the UPS do not die before utility power is restored).
Other features may vary based on manufacturer size and model. Features include line conditioning, surge suppression, advanced battery management, and communications port. Typically the more advanced features (such as double-line-conversion are reserved for the more expensive and much larger models starting at around 6kVA).
Be sure you choose the correct UPS size. There are usually 2 measurements that you need to consider. The first is the load. If you buy a 700VA UPS you need to make sure you pull no more than 700VA (think of the sticker you might see on the occasional lamp that states "Do not use bulbs rated higher than 60 Watts"). Finally the other measurement is the battery capacity. Based on how much power you are pulling and the amount of battery capacity you will be able to calculate the runtime when the power goes out. APC has a great UPS selector that helps you with this.
Other things to consider
Most companies invest a lot of money in their server equipment and keep them in a server room. This server room should be wired with several dedicated circuits. A dedicated circuit will ensure that your server does not share the same circuit that a microwave or refrigerator may be on. This reduces the chance of a circuit breaker from popping from an overload and isolates the noise that these types of devices are known to create.
Read up on the Guide to Choosing a UPS for a product review.
Article last reviewed: 11/05/2005