When network or IT personnel think of preventing data loss due to power supply problems they typically consider an uninterruptible power supply (UPS) or a surge suppressor for protection. Recent studies by Bell Laboratories, however, indicate that less than 4 percent of power-related problems would be addressed by such devices. Thus, even networks and computer systems that are well protected by UPS and surge protectors are at serious risk.
"Power problems caused by small surges, spikes and sags in the electricity supply cause 15 times more problems today than viruses," said Bahram Mechanic, CEO of SmartPower Systems of Houston, TX, a maker of power protection and conditioning equipment. "Servers, workstations and networking gear can best be protected by using transformer-based filters. Whereas old-style power conditioners were large and expensive, a new breed of inexpensive electronic power conditioner is being deployed today in the computer room."
Major studies of power quality by Bell Labs and IBM have found that around 80 to 90 percent of the time, electronic equipment is being affected by tiny surges as opposed to lightning flashes or blackouts. These little spikes wreak havoc in terms of logic confusion, system errors and frozen screens.
The reason this situation has remained largely under the radar perhaps lies in the fact that there are actually two distinct types of spikes and surges. Most people protect themselves against one (occurring in what is known as "normal mode") but fail to pay any attention to the other (occurring in "common mode").
Normal mode power noise causes damage to power supplies, PC board blowouts and other catastrophic issues. Common mode noise, on the other hand, causes logic confusion, data loss, system errors, blue screens or mysterious service calls that end without an actual problem being located. Relating this back to the two studies above, blackouts and large surges account for less than 5 percent of all power problems and happen in normal mode. Yet 80 to 90 percent of all problems happen in common mode.
Surge suppressors or surge protectors protect equipment from excessive voltage are relatively inexpensive and offer excellent protection against catastrophic high-voltage spikes in normal mode. However, they fail to handle the relatively small over and under-voltages that occur in common mode.
A backup power supply used when the main electrical feed has failed or drops to an unacceptable voltage level, UPS should be part of any power-protection strategy. But blackouts make up around 1 percent of power quality situations.
Isolation transformers prevent current from flowing directly from one side of a circuit to the other. These devices are an excellent way to filter out normal mode voltage spikes and common mode spikes. On the downside, they are heavier and more expensive than more modern alternatives.
Transformer-based filtering (TBF) devices provide greater functionality than traditional power conditioners. TBF units provide basic protection against massive spikes up to 6,000 volts as well as small common mode spikes and surges. In addition, they constantly monitor the line power. If voltage goes too high for more than 5 cycles (80 milliseconds), for instance, the motherboard could blow out. The TBF cuts the power off to prevent damage to the machine.
Further, new TBF technology can identify mis-wired outlets. If a ground wire is loose, or the polarity between neutral and hot is reversed, the device will not let the power reach the protected machine.
SmartPower Systems' TBF, for example, compresses all this functionality into a 17-ounce package the size of handheld cassette tape recorder. Built-in RJ11 and RJ45 connectors extend protection to telephone and network lines. Smart Power also offers UPS with TBF products. For those with UPS and surge suppressors already in place, TBF technology (model Smart Cord) can be added inexpensively to upgrade those units.