Electrical drawings are classified:
1, the system diagram or block diagram: symbols or box with notes, generalized representation of the basic composition of the system or subsystem, interrelationships and its main features of a sketch.
2, circuit diagrams: graphic symbols and arranged in working order, a detailed representation of the circuit, equipment or complete sets of all the components and connections, without regard to its actual location of a sketch. The purpose is to facilitate a detailed understanding of the role of the principle, analysis and calculation of circuit characteristics.
3, the function of the diagram: the theory of the circuit or the ideal circuit and does not involve the realization of a diagram, its purpose is to provide the basis for drawing circuit diagrams or other relevant diagrams.
4, logic diagram: mainly with binary logic (and, or, or, etc.) unit graphic symbols drawn a sketch, which only represents the function and does not involve the realization of the logic of the method of the diagram is called pure logic diagram.
Expanded Information: Steps to look at the circuit drawings: 1. Look at the main circuit of the electrical equipment. Electrical equipment refers to the consumption of electrical appliances or electrical equipment, look at the map first to see clearly there are several electrical appliances, their categories, uses, wiring and some different requirements. 2, to find out what electrical equipment is controlled by what electrical components. There are many ways to control electrical equipment, some directly with the switch control, some with a variety of starter control, some with contactor control. 3, understand the main circuit used in the control appliances and protection appliances. The former refers to control elements other than conventional contactors, such as power switches, universal transfer switches. 4, look at the power supply. To understand the power supply voltage level, is 380V or 220V, from the busbar convergence row power supply or distribution screen power supply, or from the generator set connected out. Baidu Encyclopedia - Electrical Schematic Diagram