Views: 170 Author: Site Editor Publish Time: 2021-06-03 Origin: Site
How to choose an intelligent fault indicator? Due to the need for fault detection, the use of intelligent line fault indicators is now very high, and also because the utilization rate is relatively high, the market is relatively large, and many manufacturers have also begun to produce intelligent fault passage indicators. The technical differences lead to production. The products that come out are also mixed. How should purchasers choose when purchasing? Here is an introduction to the method of selection.
The current instructions are mostly flop instructions or LED flashing instructions. The flop instructions can be clearly observed during the day when the light is good, but it is difficult to observe at night or when the light is dark, while the LED flashing situation is just the opposite. So the two should be combined, that is, the flop and flashing instructions exist at the same time, so that all-weather normal instructions can be achieved.
That is, the intelligent fault circuit indicator can work normally in the required operating environment. Generally, the method for the power line fault indicator to judge whether the line is live is to use the line current to determine whether to start judging the fault current, and some fault indicators directly use the line current to extract the working power, so there is a minimum working current Is, that is, when the line is greater than the current, the fault indicator can work normally, otherwise it is in a dormant state. The smaller the current, the better.
Generally, a fault indicator with a backup battery requires a smaller Is, and its application range is wider, while a fault current indicator that directly takes the working power from the line requires a much larger Is, generally about 10A, which will affect the use range of the cable fault indicator, for example, cannot be used on some small branches and lines with a small load. Reset time: The fault indicator should be able to distinguish between transient faults and permanent faults. For transient faults, since they can generally be eliminated after reclosing, the fault indicator is required to be maintained until the preset reset time after the power is received, which is convenient for operators to find hidden troubles and deal with them in time; for permanent faults, the fault pass indicator can be reset after the call or the preset reset time is up, mainly because the fault has been eliminated and the indication status has been maintained. There is no need, and it will even delay the next fault indication.
Because the intelligent automated cable fault indicator works outdoors, it should be able to work normally in a wide temperature range. At present, most fault indicators can be guaranteed to work normally between -40 and 85°C. At the same time, protection from rain and moisture should be considered. At present, epoxy potting technology is mostly used, and this phase index can basically be met. The working environment should also consider electromagnetic compatibility. Due to the complex outdoor electromagnetic interference, such as corona discharge and lightning flashover of nearby ultra-high overhead power lines, electromagnetic phenomena such as corona discharge and lightning flashover in nearby ultra-high voltage lines will often cause the intelligent fault indicator to malfunction or refuse to operate. Currently, this factor has not attracted great attention in China.