The constructor of the installation of high and low voltage distribution room in the factory must have the first-class qualification. The business scope must include 10KV and above.

Low-voltage centralized meter reading system, referred to as low-voltage user centralized meter reading system, refers to the system in which the main station reads the electric energy recorded values (window values) of multiple meters through remote communication channels.

First-class enterprises: can undertake the construction of transmission lines (including cable projects) and substation projects of various voltage levels;

Secondary enterprise: it can undertake the construction of transmission lines (including cable projects) of 220kV and below with a single contract amount not exceeding 5 times of the registered capital of the enterprise and substation projects with the same voltage level.

Grade III enterprise: it can undertake the construction of transmission lines (including cable projects) with a single contract amount not exceeding 5 times of the registered capital of the enterprise and the construction of substation projects with the same voltage level.