This product is used to provide a switchgear equipment circuit voltage information at the installation status to the operator. Thanks to internal circuitry of low-power light-emitting element, it lead to lower power consumption, more stable performance and higher reliability. In order to make user test double-loop phase more conveniently, indicator(recommend type) panel setting the end of the test phase, meanwhile the frame of indicator (recommend type) shell adopts front end removable. And the user can change the indicator without opening the indicator shell. Widely used for indoor 5,12,24,40.5kV, frequency of 50Hz high voltage electrical equipment, and supporting the use of the voltage sensor, it can reflect the high voltage live situation, and voltage sensor support, but also to improve the anti-error performance ancillary products.