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Advances in technology are leading to greater than ever numbers of products that contain microprocessors. We are now able to individually accomplish greater workloads; we communicate instantly with fewer boundaries; we have vast amounts of information at our fingertips. Home computers can be found in greater numbers than ever. We enjoy comforts at home not even imaginable a few years ago. We e-mail letters to our family members. A bread maker can turn itself on. A phone can show where a friend is. All of this is because of advances in microprocessor technology. As helpful as microprocessors are, they are highly vulnerable to power fluctuations. A motor turns on and sends an electrical surge through the power system. It turns off and sends a backwash of EMF through the wiring. Community provided power services have power fluctuations and dropouts. Lightning strikes create huge voltage spikes and send high-frequency RFI through electrical wires. These are just a few of the events that can damage a microprocessor. The solution has been to install a surge suppressor between the electrical service and the device. Does that really work? How long will it be reliable? A quality surge suppressor is much more than a plug strip. Here is an overview of a surge suppressor one might find. There has 8 outlets; 4 of them are transformer-spaced (they are spaced apart to allow transformers to be plugged in side-by-side). It has a Fax/Modem connection. It has LED status indicators. There is a 15-amp circuit breaker master switch. The master switch allows a user to conveniently reset the breaker if it trips. The surge suppressor is UL listed and is approved as per UL 1449 protocol (Second Edition) with a 330 volt rating. The UL 1449 Second Edition protocol is the most current standard, as of February 1998. The suppressor can absorb up to 1,380 joules of energy. It has a 76,500-amp maximum surge current rating. This product is representative of what might be found in an office or home. This surge suppressor is a plug-in type device. The voltage at which it diverts a surge to ground is 330 volts. The time required to divert the voltage is just a few milliseconds. This type of surge suppressor utilizes a type of semi-conductor to direct the voltage to ground, called a metal-oxide varistor or MOV. These semiconductors are stacked together to achieve the limits specified. The limit of 1,380 joules can be reached in one event or can be cumulative. There is a limit to the energy it can absorb before it needs to be replaced. Recently developed surge suppressors have a thermal fuse added. Older surge suppressors that do not have this thermal fuse can overheat during power fluctuations and combust. There is no indicator to gage when the MOV stack has reached it?s limit, so routine replacement is advised. Depending upon the application, this surge suppressor may not be an appropriate solution. An additional building surge suppressor might be appropriate. Power conditioning equipment and uninterruptible power supplies are increasingly being used for protection of valuable data and life-safety systems. Computers, communications systems, entertainment systems, audio/visual and lighting systems, and even appliances now utilize micro-processing technology. By far, the best insurance for protecting this technology can be a well chosen surge suppressor.