What are the precautions for selecting fault indicators?

1.Security:

Since the fault indicator is installed in the 10kV high-voltage switchgear, the indicator and the high-voltage belt part must have sufficient safety distance and insulation protection, and the internal communication adopts optical fiber, and the equipment needs to have certain fire-proof, explosion-proof, high-temperature, and ozone corrosion resistance;

2.Reliability:

First, the indicator should be able to operate stably for a long time, and the equipment body and power supply should have a long service life. Second, it is necessary to be able to operate correctly, the equipment can resist electromagnetic interference, and can avoid the influence of non-fault factors such as operating overvoltage.

3.Economical and practical.

As an accessory of 10kV switchgear, the line fault indicator is installed in a large number, and in use, it is necessary to obtain the maximum benefit with the minimum investment;

4.Easy to use and maintain.

It is convenient to read the fault information, to replace the battery, and to replace the indicator.

The selection of fault indicators must be based on the requirements of their own use environment, and generally there will be the following indicators to choose the fault indicators they need:

1, the way of indication: the current indication is mostly the flop indication or LED flash indication, the flop indication can be clearly observed when the light is better during the day, but it is difficult to observe at night or when the light is dark, and the situation of LED flash is just the opposite, so the two should be combined, that is, the flop and flash indication exist at the same time, so that the normal indication can be achieved around the clock.

2. Normal working conditions: that is, the fault indicator can work normally in the required operating environment. The general fault indicator method of judging whether the line is live is to use the line current, so as to decide whether to start judging the fault current, and some fault indicators directly use the line current to extract the working power supply, 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, the fault indicator with backup battery requires that the IS will be smaller, and its application range is wider, and the fault indicator that takes the working power directly from the line requires much larger, generally about 10A, which will affect the use range of this fault indicator, such as in some small branches and lines with small loads. Reset time: the fault indicator should be able to distinguish between transient fault and permanent fault, for transient fault, because it can generally be eliminated after reclosing, the fault indicator is required to be able to maintain the pre-set reset time after the call and then reset, so that it is convenient for the operator to find out the hidden danger of the fault and deal with it in time; For permanent faults, the fault indicator can be reset after the incoming call or after the preset reset time, mainly because the fault has been eliminated, it is no longer necessary to continue to maintain the indication state, and even delay the indication of the next failure.

3. Normal working environment: Since the fault indicator works outdoors, it should be able to work normally in a wide range of temperatures, and most of the fault indicators can be guaranteed to work normally between -40 and 85. At the same time, rain and moisture protection should also be considered, and epoxy potting technology is mostly used at present, and the phase indicators can basically be met.

The working environment should also consider electromagnetic compatibility, due to the complex outdoor electromagnetic interference, such as the corona discharge of the nearby ultra-high voltage line, lightning flashover and other electromagnetic phenomena, often lead to the fault indicator misoperation or rejection, this factor has not been paid great attention to in China. The choice of fault indicator can refer to the above three conditions to choose, the best source on the market is a number of comparisons, large-scale production manufacturers are generally the best goods, national qualifications are certified.

The function of the fault indicator: in the ring network distribution system, especially in the system that uses a large number of ring network load switches, if a short circuit fault or grounding fault occurs in the next level of distribution network system, the power supply system of the upper level must be broken within the specified time to prevent major accidents. By using this product, it is possible to mark the part that is faulty.

According to the alarm signal of this indicator, the maintenance personnel can quickly find the faulty section and disconnect the faulty section, so as to restore the power supply of the fault-free section in time, which can save a lot of working time, reduce the power outage time and power outage range. The following points should be paid attention to in the selection of "fault indicator detection device":

1. Short-circuit fault action Hu Wei current: 150A 1500A.

2. Grounding fault action current: 10A-100A.

3. Power: standby; Instructions.

4. Power supply: lithium battery.

Attention should be paid to the use of fault indicator detection devices:

1. Short-circuit alarm indication: the short-circuit sensor detects the current in the power supply line at all times, and when its value reaches or exceeds the short-circuit electric "flow start-up alarm setting value (this value can be set before leaving the factory according to the user's requirements), the short-circuit sensor sends a signal after the host receives this signal through the optical fiber, and generates an alarm indication signal (the indicator flashes quickly).

2. Grounding alarm indication: When the grounding sensor detects that the current in the grounding line reaches or exceeds the grounding current and starts the alarm is insufficient (this value can be set according to the user's requirements before leaving the factory), an alarm signal is issued, and the host receives this signal through the cable or optical fiber, and generates the corresponding alarm indication signal (indicator flash).

3. Battery low battery alarm indication: when the battery voltage in the indicator drops from down, an alarm signal will be generated to prompt the maintenance personnel to replace the battery.

4. Remote transmission of alarm information: the indicator host can drive the corresponding relay action according to different alarm indication signals for remote transmission of signals.

5. Automatic reset: When the indicator generates an alarm, the indicator can be automatically reset if there is no manual reset within the setting time.

6. Test and reset: When the indicator of the beam chain generates an alarm and the fault is eliminated (the indicator flashes slowly), the alarm state can be cleared by pressing the button on the panel of the indicator host. In the normal state (no alarm signal), you can press the button on the front panel and hold it for 1 second, the short circuit and grounding alarm indicator on the panel flashes, and the fault remote relay is engaged, indicating that the working state is normal, and then press this button after it becomes a slow flash (after 2 seconds) to return to normal.

**The smart power fault indicator has the following features:

1.The fault indicator monitors the line status in real time and provides data basis for intelligent decision-making2The monitoring indicators are abnormal, automatic flashing, flop alarm, and remote transmission to the main station 3Fault points are visualized, and the line status is clear at a glance.

4.Remote configuration of equipment and remote upgrade of programs, greatly improving management efficiency5Epoxy casting, fully sealed structure, can be used for long-term outdoor maintenance-free operation6

Powerful power solution: card wire power + solar power supply + low power consumption optimization7The smart grid fault location system has added another sharp weapon:

Transient fault recording indicator.

Short-circuit fault operating current: 150A 1500A

Ground fault operating current: 10A-100A

Accuracy: 10%.

Ambient temperature: -25 70

Ambient humidity: 40 relative humidity 95%.

Power: Standby; Instructions.

Power supply: Lithium battery.

Auto-reset time: 7sec-2h-4h-8h can be set, other settings can be booked output relay contact capacity: 230V AC 1A 125VDC 1A 30VDC 2A

Dimensions (w h d).

Panel mount reading meter: 92 46 63mm

Surface Mount Reading Meter: 92 140 42mm Sensor Short Circuit Sensor: 38 38 26mm Earth Fault Sensor: 38 38 26mm

The Short Circuit and Ground Fault Indicator consists of the following parts:

Three short-circuit fault sensors.

A ground fault sensor.

A reading meter.

The connecting wires are cables and or fiber optic cables.

The reading meter is packed in a plastic box, the reading meter is equipped with a time reset circuit and an assignment circuit, the ground fault is indicated by a flashing LED light, and the short circuit fault on each cable is indicated by a flashing LED light to indicate that the reading meter is equipped with a test reset button Each sensor is composed of a plastic housing and a coil that detects the pulse current caused by a short circuit and a ground fault, depending on the different versions of the sensor, the connecting wire is either fixed to the sensor, or the sensor is plugged in by optical fiber, The enclosure is injection molded and meets the conditions for IP use. The fibre optics are manufactured by PMMA and have an effective length of up to 10 meters for the safe transmission of finger grinding between the sensor and the reading meter in a high-pressure area.

There are many types of fault indicators, and you don't know what type you need.

Simple: Flop indicator glows after a short circuit or ground fault. The advantage is that the lineman can find the fault point without climbing the pole, and the disadvantage is that the signal cannot be transmitted, and the line needs to be inspected along the way, and the accuracy of detecting grounding faults is very low.

Two remote fault indicator: now used more, the advantage is that the fault can be sent to the background and the staff mobile phone in time, the disadvantage is that the accuracy of detecting grounding faults is low, and the cost is high.