Aiming at the incoming line switchgear cabinet characteristics of 12 kV distribution network terminal substation and main unit,this paper presents a multifunctional digital protection set of terminal user switchgear based on 16-bit microprocessor.

The principle, function and design of a microcontroller-based protection unit for substation and switchgear of terminal user is described in this paper.

Based on the causes analysis of burning accidents of indoor terminal of 35 kV cross-linked power cable with single core and repairing procedures,the improvement methods and lessons to be drawn were raised.

This paper introduces the design of the user terminal hardware system with the 89C55 MPU.

In view of the roles of owner in project management as middle investor of terminal clients and main body in project management the related management strategies should be adopted by the owners are proposed in this paper.