Discuss what quality inspection indicators for bttz cables
The inspection of bttz cables has always been a major stage in the national standard wire and cable. The higher the quality inspection department within a bttz cable company
The inspection of bttz cables has always been a major stage in the national standard wire and cable. The higher the quality inspection department within a bttz cable company, the better and more reliable the wire and cable produced by the company will be. The key detection indicators of bttz cables are detailed below. These are important indicator values for wires and cables.
1. Measurement of DC resistance of transmission lines
The conductive core of the wire and cable mainly transmits electromagnetic energy or electronic signals. The resistance of the cable is the main indicator of the characteristics of the electrical equipment. When the AC current function is used, the wire core resistor is larger than the AC voltage function due to the skin effect and the adjacent function surface, but when the electrical operating frequency is 50Hz, the two are not far apart. Nowadays, the standard only stipulates whether the resistance measurement of the test station core or whether the resistance is higher than the required value in the specification. According to the inspection of this item, some defects in the production process can be found, such as broken power lines or part of the single-track railway. Cracked, wire cross-section does not meet the regulations, the size of the product is wrong, etc.
2. Detection of grounding resistance
The grounding resistance type reflects the key index value of the insulation layer of the bttz cable product, which is closely related to the compressive strength of the product, the dielectric loss, and the gradual deterioration of the insulation layer material under the operating state. For communication cables, if the indirect ground resistance of the wires is too low, it will continue to expand the control loop loss, the serial frequency between the control loops, and the long-distance power supply system leakage on the conductive core. Therefore, it is stipulated that the ground resistance should be higher than the standard value.
3. Accurate measurement of capacitors and loss factors
The bttz cable is coupled with the alternating current, and the amount of current also passes through. When the peak-to-peak value and number of times of the current are constant, the size of the capacitor current is proportional to the capacitor (Cx) of the bttz cable. For high-voltage cables, the amount of current of these resistors is likely to be comparable to the rated voltage, which becomes a key factor in limiting the volume and transmission distance of bttz cables. Therefore, the resistance of the cable is one of the key electrical technical parameters of the cable. According to the measurement of capacitors and loss factors, it can be found that the insulation layer is wet, the bttz cable sheath and shielding layer are falling off and other insulation layer deterioration conditions. accurate measurement.
4. Insulation strength test
The insulation strength of wire and cable refers to the ability of the insulating layer structure and insulating layer material to bear the effect of electrostatic field without penetrating and destroying. Dielectric strength tests are required. Dielectric strength test can be divided into AC withstand voltage test and penetration test. The working voltage for a long time generally exceeds the rated working standard voltage of the test product. The actual voltage value and pressure resistance time are required in the product implementation standards. According to the AC withstand voltage test, the reliability of the product operating under the rated voltage can be honed. And find serious defects in the insulating layer, you can also find some defects in the production process.