What is Power Factor?
Power factor is a measurement of how the incoming power is being used by a piece of equipment. Most computer equipment has a power factor of 0.7. This basically means that the equipment is using 70% of the incoming VA. For example, a computer designed to use 100 VA at a 0.7 PF is using 70 Watts. Liebert UPS systems are designed to output power with a 0.7 power factor so that the connected equipment does not waste power by not using it. Some equipment is power factor corrected, meaning its power factor is very close to 1.0. This type of equipment is more efficient because it is utilizing more of the incoming power and for all practical purposes the VA rating is the same as the Watts. All of Liebert’s on-line UPS systems are power factor corrected to work with any type of equipment and to be as efficient as possible.
Not all the current in the electrical distribution system is used for doing useful work at customers’ premises. Simplifying dramatically some of it is simply current that washes back and forth. Power factor is a measure of how much of the current is doing useful work as a fraction of the total current – the electricity company would like the power factor to be as close to one as possible. The power factor is never greater than one and often is between 0.6 and 0.9 and is sometimes written as cosθ because it can be depicted as the angle in a triangle that electrical engineers draw. When the power factor is low the electrical distribution companies have to put in extra large cables, generating stations, and special power factor correction equipment to make sure that the consumers at the end of the line still get the power they need. In some countries consumers who have poor power factors are directly charged extra for this, and in other countries the extra cost is spread across everyone i
Power Factor is the measurement of how efficient your facility is using the power that is being supplied by the utility company. When looking at an individual piece of equipment, the Power Factor of that piece of equipment is the expression of its operating efficiency. For example, if the Power Factor measured at the equipment is 75%, then that piece of equipment is only operating at 75% efficiency.
Power factor is a measurement of the efficiency of the ballast in terms of the ratio of wattage entering the lamp and the wattage entering the ballast. The closer to 1 the power factor is, the more efficiently the ballast is working. Above a .70 power factor is considered a High Power Factor. Between .50 and .70 is a Normal Power Factor. The THD is higher with a normal power factor.
