A monitoring cable is a general term for various wires that transmit electrical or optical signals. The monitoring cable is usually a covered wire. The copper wire and the steel wire are mixed and twisted into a conductive core. The outer sheath is made of an insulating material. It is tensile and wear resistant. It is easy to retract and reuse. There are mainly video cables and RF wires. Shielded and unshielded, signal lines, control lines, etc., various models.

Identify the quality of the monitoring cable

1. Sheath: The surface can be seen to have a regular "unevenness" in the inner mesh, which indicates that the processing technology is good and does not produce relative sliding,it is a good cable. The appearance is smooth, and the "unevenness" of the compacted net is not seen. The hand-pinched jacket has a loose feeling, which is a poor cable;

2. Check the shield layer network: Is the shielding coverage density enough? Copper mesh, check for solderability, tinned copper wire scrape to see if it is copper wire, the mesh is sparse, uneven distribution, and the insulation layer is not tight, etc. is the difference cable;

3. Check the adhesion between the core wire and the insulation layer: cut the insulation layer obliquely, and pull the core wire in the peeling direction to see if the core wire and the insulation layer are in contact with the process material; the cable has a large adhesion force and is poor. The cable is not glued;

4. Longitudinal tensile test: Take one meter of cable, peel off the core wire, insulation layer, shielding layer, and outer casing, each leaving 10 cm long. The method is: two hands respectively hold the adjacent two layers of the cable and pull in the opposite direction; the good cable generally pulls the power, and the difference cable can be easily pulled out without much effort - the elevator cable is very important, many so-called "Elevator-specific cables" have problems in this regard;