signal to one. Reset of the start and trip signal can be instantaneous or time delay inaccordance with the setting.9.1.2.5 Built-in overvoltage protection stepsTwo overvoltage protection steps are available. They are absolutely identical andtherefore only one will be explained here.Overvoltage step simply compares the magnitude of the measured voltage quantity(see table 169) with the set pickup level. The overvoltage step will pickup if themagnitude of the measured voltage quantity is bigger than this set level. Reset ratiois settable, with default value of 0.99.The start signal will start definite time delay or inverse (IDMT) time delay inaccordance with the end user setting. If the start signal has value one for longertime than the set time delay, the overvoltage step will set its trip signal to one.Reset of the start and trip signal can be instantaneous or time delay in accordancewith the end user setting.9.1.2.6 Built-in undervoltage protection stepsTwo undervoltage protection steps are available. They are absolutely identical andtherefore only one will be explained here.Undervoltage step simply compares the magnitude of the measured voltagequantity (see table 169) with the set pickup level. The undervoltage step willpickup if the magnitude of the measured voltage quantity is smaller than this setlevel. Reset ratio is settable, with default value of 1.01.The start signal will start definite time delay or inverse (IDMT) time delay inaccordance with the end user setting. If the start signal has value one for longertime than the set time delay, the undervoltage step will set its trip signal to one.Reset of the start and trip signal can be instantaneous or time delay in accordancewith the end user setting.9.1.2.7 Logic diagramThe simplified internal logics, for CVGAPC function are shown in the followingfigures.Section 9 1MRK 505 208-UEN BMultipurpose protection278Technical reference manual
