1. Classification of insulated wires
Answer: insulated wires often are the following: PVC insulated wire, PVC insulated wire, PVC nitrile mixture of insulated cords, rubber insulated wire, buried underground agricultural plastic insulated aluminum wire, rubber insulation cotton textile cord, PVC insulated nylon sheathed wire, PVC insulated power and lighting cords etc..
2, cable bridge suitable for what occasion?
Answer: the cable tray is suitable for the general industrial and mining enterprises, indoor and outdoor overhead laying wire and cable, control cable, can also be used for telecommunications, radio, television and other departments in indoor and outdoor erection.
3. Types of cable accessories
Answer: commonly used electrical accessories are cable terminal box, cable intermediate junction box, connecting pipe and connection terminal, steel plate connection slot, cable bridge frame and so on.
4. The meaning of the cable intermediate joint
Answer: connecting cables and cables conductor, insulation shielding layer and protective layer, so that the cable line connection device, known as the cable intermediate connector.
5, what is the main electrical connector?
Answer: the main electrical wiring is connected in the main electrical equipment and bus power plant, substation, including the connection bus and auxiliary power system according to certain functional requirements.
6, in the selection of power cable section, which should comply with the provisions?
Answer: the selection of power cables shall comply with the following principles:
(1) the rated voltage of the cable shall be greater than or equal to the rated voltage of the power supply system of the installation point;
(2) the continuous permissible current of a cable shall be equal to or greater than the maximum sustained current of the power supply;
(3) the core section should meet the requirement of stability when the power supply system is short circuited;
(4) check whether the voltage drop meets the requirements according to the cable length;
(5) the minimum short-circuit current at the end of the line shall enable the protection device to act reliably.
7, what are the advantages of XLPE cables and oil paper cables?
Answer: (1) easy to install, because it allows minimum bending radius is small, and light weight;
(2) not limited by line drop;
(3) good thermal performance, allowing high operating temperature and large transmission capacity;
(4) the cable accessories are simple, all dry structures;
(5) simple operation and maintenance, no oil leakage;
(6) the price is lower;
(7) high reliability and low failure rate;
(8) the manufacturing process is few, the process is simple, and the economic benefit is remarkable.
8 、 What are the requirements for fixing the fixture of AC single core cable? Why?
Answer: the fixture should be no iron to form a closed magnetic circuit, this is because when the cable core through the current, generating a magnetic flux in the surrounding magnetic field and current through the wire core is proportional to the size, if the use of iron magnetic material, on the basis of electromagnetic induction that will produce eddy flow to cable heating in iron castings. And even burn the cable. Therefore, the iron piece can not be used as the fixing clamp for the single core AC cable.
What are the main features and advantages of the accessories for heat shrinkable cable heads 9 and under?
Answer: the biggest characteristic is to use heat shrinkable accessories stress stress cone tube to replace the traditional one. It not only simplifies the construction process, also reduced the size of the terminal, connector installation convenient, time-saving and labor-saving, superior performance, save metal. The heat shrinkable cable accessories are assembled by pouring type and dry bag type, and the advantages of the two attachments are assembled.