Background: The Okay cable incident actually reflects the long-standing counterfeiting problem in the cable industry. In fact, as Party A (owner) and Party B (project contractor), when selecting cable products or cables, they can make a quick test on the planned or purchased cable products to prove whether their quality meets the electrical parameters. Claim. The inspection can be completed within 15 seconds and can be implemented on the project site.
Today, we share with you how the Fluke Network Tester can quickly detect fake cables.
1, the wire diameter is thin, cut corners
Wire diameter is the most common method of falsification. For example, the standard requires the use of wire gauge No. 23 (AWG23), and the cable printed mark is also AWG23, but the wire gauge No. 26 (AWG26, finer wire diameter) is actually used. If you don't have a vernier caliper in your hand, it doesn't matter, you can test the resistance value to help determine. The tapered copper loop resistance value is larger than the normal diameter copper cable. The loop resistance test results can be given in seconds using the Fluke DTX or DSX Series cable tester. Another consequence of the thinner wire diameter is the large loss, which leads to insufficient signal transmission distance or weak signal strength. The DTX/DSX cable tester can directly give the loss value (attenuation value). An unqualified cable will give an alarm. The 100-meter sample can be cut according to the standard (instrument built-in standard), or the whole box line (305 meters) can be used for testing (DSX series). According to experience, the data cable is often the hardest hit area, the communication bus (twisted pair), and the control bus are slightly better.
2, abnormal material, non-copper alloy
Copper is made of inferior copper or other alloys, and even worse is copper-clad aluminum (CCA) or copper-clad iron (CCFe). The average user only uses the vernier caliper to measure the wire diameter, which is impossible to find. The DTX/DSX can detect the abnormality of the copper material by testing the loop resistance, insertion loss, return loss and other parameters of the copper wire in 8 seconds.
3, the interference between the pairs is too large, the processing is not in placeThe data cable and part of the bus are composed of multiple pairs of twisted pairs (4 pairs, 2 pairs). If the twisted pair has a low twist ratio (which can save material), the electromagnetic radiation crosstalk between the pairs is relatively large, and the pair interferes with each other when transmitting data, resulting in an increase in the packet loss rate when the signal data is transmitted at a high speed, and the data transmission is intermittent. Sometimes there is no fault, sometimes the production line is inexplicably interrupted, and even when the communication is completely interrupted. However, data transmission at low speed may not find such a problem of cutting corners. The crosstalk parameter (NEXT) is found to be unacceptable through the DTX/DSX test.
4, the wire pair manufacturing is uneven, the manufacturing precision is too low
Low manufacturing precision results in uneven cable structure and large signal reflection (echo), which can interfere with twisted pairs and buses that are used for both signal transmission and signal reception. The DTX/DSX test results show "Failed". In addition, uneven manufacturing can also cause the signal cable to be resistant to external interference, and sometimes there is no erratic failure phenomenon. The DSX can detect whether its anti-interference indicator (TCL/TCTL/unbalanced resistance, etc.) is up to standard.
5, the installation is rude, the link is not availableSometimes, although Party A has purchased high-quality products with a high budget, the actual use effect is not satisfactory. Indicators such as error rate and frame loss rate are not good or unstable. This has a lot to do with the construction level of Party B. The construction level of the construction team from the guerrillas on the road is usually not guaranteed. After all, communication lines, signal lines, control lines, etc. are more professional in terms of the fineness of installation. For example, if the twisted pair is too long, it will cause crosstalk between the pairs to increase; the joint is too deformed or excessively kinked, and the binding is too tight and too tight, which will cause excessive echo interference; the cable bundle is too large (for example, more than 48) The bundle of the roots will also cause excessive interference between the cables. These can lead to problems such as increased error rates, good times and bad times, and unstable communication and data transmission. In the case of a broken or lost key command frame of the subway signal transmission, it may cause a disaster of control error, causing a major traffic accident. Using DTX/DSX to detect the installed link, problems such as unqualified parameters caused by these improper operations will be exposed. And DTX / DSX can directly locate the fault location, such as reporting 23.7 meters of crosstalk or echo parameters failed within 15 seconds.
6, frequent failures, quality assurance is not in placeUsing poor cable construction, although various applications can operate normally at the time, but due to the unqualified link left to the system the margin is too low, when encountering cable aging, vibration and wear, high temperature and high humidity, air pollution (sulphur dioxide, etc. Oxidation/blackening of the copper contacts, deterioration of the electromagnetic environment, etc., will gradually appear flashing or a variety of inexplicable problems, making maintenance personnel a big headache. The DTX/DSX provides unqualified link detection reports to the acceptance maintenance personnel and indicates the approximate cause and physical location of the failure. With the implementation of the regular inspection and visual inspection system, the communication reliability of the cable link can be maintained at a sustainable high reliability level.
Due to the pre-installed copper cable, although it can support low-speed applications, the parameters are unqualified. Generally, when the network is upgraded or expanded later, the problem of large batches of high proportions will be discovered. But at this time it is often too late. It is necessary to stop work or stop normal business, and to replace the qualified cable in batches in order to be “reassuringâ€. In the inspection test, approach test, engineering acceptance test, etc., the DTX/DSX cable analyzer can be used to tell you the reason for the failure of this link and its location within 15 seconds. The Fluke Detector is hand-held and can report pass/fail results directly and give a red symbol prompt for easy use.
8, the environmental design is not considered, the work is unstableSometimes, the selected products and installation and construction are qualified, but the copper link is still intermittent, high packet loss rate, unstable work, etc., except that it is not related to long-term periodic inspection (such as natural aging). The main reason is that there is no pre-assessment of the electromagnetic interference environment of the work. Interference environments such as subways, high-speed rails, and industrial sites are sometimes difficult to assess in a comprehensive and accurate manner. Due to new sources of interference caused by personnel gathering, subsequent upgrades and expansions, interference is difficult to track and prior assessment. The solution is to use a cable product with a high level of interference immunity (the anti-interference indicator is the balance parameter mentioned above). Copper cables with good anti-interference parameters and suppliers with stable quality can be selected in the selection stage. The DSX can test the balance parameters (TCL, TCTL, unbalanced resistance, etc.) in advance to help Party A evaluate the anti-interference ability (E1, E2, E3, with the highest E3 level). For Party A that requires high reliability, consider using E3 grade cable products.
9. There is a difference between the selection and the actual supply.
During the design and bidding phase, Party A may request Party B and the supplier to conduct the selection test. However, it was discovered afterwards that there was a significant quality difference between the samples provided during the selection and the products actually supplied. Therefore, the better way is to insist on the purchase test (usually the test). DTX/DSX can easily detect the quality of cables, jumpers, connection modules, etc. The general test time can be completed within 15 seconds.
Compact Temperature Sensor We have many products in marine temperature sensors, and our small marine temperature sensors have been traveling in various oceans. Our sensors are not only used in ship mechanical equipment, but also used in freight yards. Our small marine temperature sensor can be used to monitor the marine mechanical equipment and the temperature and humidity in the warehouse. Moreover, our sensor has been used in the oil separator module for a long time, and its performance is very stable.
Compact Temperature Sensor,Small Temperature And Humidity Sensor,Smart Temperature Sensor,Hydraulic Temperature Sensor
Taizhou Jiabo Instrument Technology Co., Ltd. , https://www.jbcbyq.com