久久精品久久久久,亚洲国产精品欧美日韩一区二区,久视频免费精品6,日本在线不卡视频

Selection of qualified cables for security engineering

release:admin Browse:4044 times

Cables are widely used in security engineering. Whether it is CCTV TV monitoring, entrance and exit control, or anti-theft alarm, fire alarm, public broadcasting, intelligent wiring, automatic remote meter reading and other systems are inseparable from the cable pin. If the security system is likened to the human body, then the wire and cable products used in the security system are like blood vessels and meridians scattered throughout the human body, and its importance is self-evident. Engineering maintenance has proven that high-quality security cables are important for ensuring project quality and extending project life. Therefore, users and engineers should pay special attention when selecting cables. In general, when choosing a security cable, you should consider the following five aspects:



    I. Enterprise qualification, product quality inspection certificate and customer evaluation



    When users or engineers purchase security cables, the first thing they need to pay attention to is the enterprise and product qualification materials. You need to know the following types of qualification certificates:



    1. The business license, organization code certificate, tax registration certificate, etc. can all indicate the scale strength and enterprise grade of the production enterprise.



    2. National industrial product production license (wire and cable), CCC China National Compulsory Product Certification, Information Industry Ministry Network Access Certificate, ISO9001 certification and other certificates are the necessary production and operation license qualifications and enterprise quality management level of the production enterprise. Sign. Among them, in addition to the ISO9001 certificate, other types of certificates are required, and vice versa are products that are illegally produced or operated.



    3. The quality inspection report of the national authoritative department within the validity period can fully prove that the production enterprise has reached the national standard for the production and quality control of the tested products.



    4. Other certificates or documents, such as industry member certificates, honor certificates, certification certificates, patent certificates, etc., are strong proofs of the user's recognition, influence and overall strength in the industry.

    The formal production enterprises rely on the comprehensive strength of the enterprise, and have obtained various national certifications, and the relevant qualifications are complete. In the daily production and manufacturing process, the quality of products is subject to the supervision and inspection of the national authorities from time to time, and the quality and service are guaranteed. At the same time, the qualifications of complete enterprises and products are also the conditions that must be met for the acceptance of security projects.



    5. Cases of large-scale engineering projects, such as large-scale project atlas, photos, contracts, etc. Because large-scale projects usually have high requirements on the production capacity, quality and price of suppliers.



    6. Is there a customer evaluation book for the project? Under normal circumstances, if the project is indeed satisfactory, the customer will issue a satisfactory evaluation of the product. Large projects will even issue relevant certificates.



    Second, cost performance and service



    When users purchase security cable products, after understanding and carefully reviewing the relevant qualification documents of the production enterprises, the performance and price of the products, as well as the service and supply guarantee capabilities, should be comprehensively measured.



    As an engineering contractor or direct user, it is inevitable to maximize the use efficiency and value at the most reasonable price with the same product quality. At present, the various specifications of cables required for security system engineering are generally guaranteed by mainstream security cable companies in the industry. Therefore, some users esteemed foreign brands one-sidedly, and the consumption concept of high-priced cable products is irrational. Similarly, blind pursuit of low prices and neglect of product quality are not advisable. It should be fully recognized that according to the laws of the market economy, reasonable prices mean reasonable quality assurance.



    The homogenization of products in today's market has become a development trend, and the price difference is becoming less and less obvious. It makes the service guarantee of products more and more important. The use characteristics of engineering supporting products require the production enterprise to provide full service, from the design of the system engineering plan to the on-site construction and acceptance of the project, from the normal operation of the guarantee system to the follow-up maintenance in the future, and the change of the design plan during the construction process. Many changes, such as individualized needs, require manufacturers to not only have the corresponding technical strength, but also need a quick response and a sound service guarantee system. Therefore, stable and reliable product performance, reasonable price and perfect service guarantee are all important links in the purchase of security cable products.



    Third, the manufacturer's field trip



    When purchasing cable products, users are also very important to the scale of the manufacturer and the field inspection of the production base. There is a saying that "early hearing is false, seeing is believing". The speciality of cable product performance determines the professionalism of cable detection methods. Generally, users are accustomed to judging the quality of cables from appearance and feel, but their true technical performance and parameters must rely on professional cable testing equipment. Can be achieved.



    The quality of cable products is mainly determined by the following aspects: procurement of raw materials; production and testing equipment; production process and production process control. When the user visits the production site, the above points can be used to understand the degree of cable quality assurance.



    At present, there are a large number of family-owned cable manufacturers in China, which are small in scale and single in product variety. In order to pursue profits and reduce costs, they purchase inferior unqualified raw materials, but counterfeit other well-known brands in the market. Or use a variety of media and propaganda tools to package businesses and products to blindly unknowing consumers. Therefore, when purchasing a large number of products or selecting long-term cooperation suppliers, it is especially important to inspect the production site, and it is really better to see it.



    Fourth, product acceptance and quality identification



    When the user accepts the product, it can be identified from the following aspects to determine whether the product meets the standard. Considering that users are unlikely to have professional testing equipment, here are a few simple and effective methods:



    1. The main materials for security cables are copper and polyvinyl chloride (PVC). The quality of the material can be identified with the naked eye.



    1) The copper conductor must be shiny, soft and have good tensile strength. On the contrary, the copper conductor has poor gloss and blackness, or it has been oxidized. The conductor that is broken by hand may be a defective product.



    2) PVC material should be smooth, smooth and fine. If the surface is rough, it not only indicates that the plastic material, processing technology and plasticizing performance are poor. At the same time, if the plastic surface has large pores, it is easy to get wet and affect the product performance. In addition, the tensile strength of the plastic is also very important. If it is easily peeled off by hand, it may be a material with unqualified quality.



    3) Observe whether there is tensile protection material between the cores in the cable structure. The use of these materials can effectively protect the internal structure of the cable and improve the tensile strength of the product during construction.



    4) Use a micrometer to measure the size, thickness, diameter, etc. of the product to meet the requirements.



    2, structural process testing

    When the user accepts the product, the outer sheath of the cable can be peeled off to perform structural process inspection of the product. Focus on the following items:



    1) Whether the copper conductor is twisted or not is an irregular manufacturer. This important process is omitted. If the copper conductor is not twisted, the conductor structure may be unstable. When the cable is bent, the construction may easily cause the insulator to crack or the conductor thorn. Through the insulation layer.



    2) Whether the cable pitch is too large The cable pitch refers to the node distance of the multi-core cable after the core wire is twisted in the production process. In order to control costs and increase production speed, some manufacturers tend to enlarge the cable pitch. Therefore, the softness of the product is poor, and the internal structure is unstable, so that the performance of the cable product is degraded.



    3) The insulating plastic should be tightly packed on the conductor without damaging the conductor, and the conductor should not be eccentric.



    4) The outer sheath is tightly wrapped on the inner structure, the gap should not be too large, and the outer sheath and the inner structure have a polyester wrapping film to effectively prevent mutual adhesion.



    5) The quality of the shielding structure in the shielded cable is extremely critical for the product in the security system engineering. Requires close coverage, rules and peace. In addition to the high production process requirements of the production enterprises, the production equipment is very critical. At present, several major domestic security cable companies use high-precision PLC-controlled knitting machines. The products produced by such equipment are stable in structure and arranged in rules. Excellent shielding performance is guaranteed.



    6) The outer diameter is uniform and the roundness is acceptable. Most of the security cables are used in engineering projects. The main considerations of production companies are stable product structure and excellent transmission performance. Therefore, the roundness of the appearance is generally not deliberately emphasized.



    3, professional equipment testing

    A more accurate test method is to add professional testing equipment, or commission a specialized agency for product testing. The routine testing items and testing equipment are as follows:

    Withstand voltage test - pressure test bench

    Structural inspection - projector or measuring microscope

    Conductor resistance - DC bridge

    Conductor monofilament diameter - micrometer micrometer

    Power-on test - multimeter

    Tensile force - tensile machine



    4, other matters needing attention

    The specification of the cable delivery length, the quality of the package, the certificate of conformity, and the logo mark are unified, the name of the factory, the address, the accuracy of the phone number, and so on.



    5. Product additional functions and value-added services



    Excellent security cable manufacturers, with excellent product quality and perfect service, not only have good corporate and brand image in the industry, but also provide users with more additional functions in product application in security systems. For example, on the basis of the function of the ordinary security cable, the flame-retardant and anti-freezing functions are added; the length of the code meter is realized on the cable identification to facilitate the user's construction; and, for example, the product is provided for the user. Services such as cargo and recycling projects, such as the remaining zero-head line, control the waste of materials from the standpoint of users. Some powerful security cable companies have become more and more aware as the scale of the company continues to expand, and the scope of services has been extended from simple supply to provide system solutions for users, from direct product offering to Participate in the project bidding of users and participate in important aspects such as construction, acceptance and maintenance of the project.



    To provide users with advanced solutions to solve the practical problems encountered in the construction of security projects for customers, fully embody the additional functions and value-added services of the products. Let users experience the value of their products when they purchase products.

 


    Mastering the correct method of purchasing security cables, choosing one or several products with good performance, moderate price, timely delivery, good service, and good reputation as a long-term partner is necessary.