Conventional electrical installation works are divided into strong current, weak current and fire control linkage system. Difference between the conventional installation engineering laboratory electrical installation engineering, embodied in electrical aspect, mainly is the laboratory power supply system according to different equipment power consumption, size from a few watts to kw ranging, possibly involving three-phase alternating current (ac), or use to abnormal voltage conditions, scientific management of laboratory, modernization and intellectualization of weak current system also put forward higher requirements.