Phase sequence indicators quickly determine the phase direction of rotation in all areas where three phase power supplies are used. They feed motors and electrical systems, for example. LCD displays or LEDs display the three phases and the direction of rotation. If a phase failure is detected, the corresponding diode displays the phase. Phase sequence indicators are equipped with appropriate connection lines, thereby ensuring a simple and reliable method of testing. Contactless phase sequence indicators provide greater safety, since insulated cables can also be tested directly. This is particularly beneficial in industrial environments, where generators or energy distributors are used.