3.3 APPLICATION NOTES3.3.1 OVERVOLTAGE SETTING GUIDELINESThe provision of multiple stages and their respective operating characteristics allows for a number of possibleapplications:● Definite Time can be used for both stages to provide the required alarm and trip stages.● Use of the IDMT characteristic allows grading of the time delay according to the severity of the overvoltage.As the voltage settings for both of the stages are independent, the second stage could then be set lowerthan the first to provide a time-delayed alarm stage.● If only one stage of overvoltage protection is required, or if the element is required to provide an alarm only,the remaining stage may be disabled.This type of protection must be co-ordinated with any other overvoltage devices at other locations on the system.P14x Chapter 10 - Voltage Protection FunctionsP14xEd1-TM-EN-1 215
