Although lightning is the most critical external source of surge generation, there are other internal sources which may cause serious damage to the system. These include switching of power circuits, the operation of electrical equipment by neighbouring industries, the operation of power factor correction devices, and the switching and clearing of faults on transmission lines. All these may generate transient – a momentary variation in voltage impairing the system. It is estimated that 70 – 85% of all transients are generated internally. Fortunately, this can be prevented by implementing the patented Transient Discriminating (TD) technology embedded surge protection device that ERICO has developed.
Generally in the traditional technology, the surge protection device just disconnects safely during a temporary over-voltage event (such as lightning) and needs to be replaced immediately or else the surges can harm the system. However, with the TD technology, the patented Quick-Switch allows robust protection to limit the incoming transient and helps providing safe and reliable transient protection even after a temporary over-voltage condition has occurred. Unlike the traditional technology, the TD technology allows a continuous protection from multiple surges and also provides the surge protection device to have a much longer operational life. Though ERICO provides both options for traditional or TD technology, the latter is the better option.
With the modern industry being highly dependant on electronic equipment and automation to increase productivity and safety, using TD technology will be able to prevent these from disruptions and replacements, therefore preventing downtime of the system and maintenance work. It is recommended that the cost of protection should approximately be 10% of the cost of the facility’s economic risk.
There are different classes of surge protection devices, Class I, II and III. Class I protective devices are used at points of high exposure, where it might be hit by lightning directly or at the point of entry to a building fitted with a lightning protection system. Class II protective devices are used at the building’s main power entry in a non-exposed location (such as locations next to taller buildings) or at sub panels within the building. Class III are installed at the equipment themselves, they only protect them from the remaining voltage surge after Class I or II.
The transient surge filter from ERICO has replaceable surge modules, which reduces the downtime and unprotected time during maintenance with its compact, space saving design.
The surge reduction filters from ERICO reduce let-through voltages and rate-of-voltage rise and helps provide optimum protection for electronic equipment. Both the surge protection device and surge filter use the TD technology, providing increased service life.