The leakage protector is a current-operated leakage protection device, which is suitable for the grounding system of the neutral point of the power transformer, and also suitable for some IT systems with large capacitance to the ground where the neutral point is not grounded. Temporary electricity use at the construction site requires the installation of leakage protection devices, so the correct configuration of leakage protection devices plays a key role in the safe use of electricity. The following editor will give you a detailed introduction to the role of the leakage protector in the busbar processing machine.
According to the busbar installation method, there are 1 piece, 2 pieces, 3 pieces and 4 pieces of strip busbars per phase, and there are 2 pieces, 3 pieces, 10 pieces, 14 pieces, 18 pieces and 36 pieces of combined soft busbars.
However, due to the unreasonable configuration of the current leakage protectors installed on the construction site, the phenomenon that the last stage leakage does not operate and the upper leakage operates, making it difficult to find and eliminate leakage faults, which will seriously affect the construction progress. For this reason, the construction unit even removed the leakage protection device, which brought dangerous hidden dangers to the construction safety.
1. 400V security section bus voltmeter to zero.
The high-voltage circuit breaker in the leakage protector, also known as the high-voltage switch, can not only cut off or close the no-load current and load current in the high-voltage circuit, but also cut off the overload current through the action of the relay protection device when the system fails. and short-circuit current. It has a fairly complete arc extinguishing structure and sufficient current interruption capacity. The design of magnetic components is an important part of switching power supplies, because planar transformers have great advantages in improving the characteristics of switching power supplies, so they have been widely used in recent years.
5. After the equipment is started, it should run idly for 1-2 minutes, and the upper sliding plate will move 2-3 times in full stroke. If any abnormal sound or fault is found, it should be stopped immediately, the fault should be eliminated, and it can work only after everything is normal;
For an ideal transformer, the magnetic flux generated by the primary coil passes through the secondary coil, that is, there is no leakage flux. For ordinary transformers, the magnetic flux generated by the primary coil does not all pass through the secondary coil, so leakage inductance is generated, and the tight requirements of electromagnetic coupling cannot be met. The planar transformer has only one turn of the mesh secondary winding, which is also different from the traditional enameled wire, but a piece of copper skin, which is attached to the surface of multiple stamped ferrite cores of the same size.
2. The replacement of some printed circuit boards requires some specific operations after the replacement to complete the establishment of software and parameters.
1. Judgment that the zero line is disconnected
In the single-phase power supply range of the busbar processing machine, the zero line is disconnected, the lights in the fault range are not on, and other electrical appliances cannot be used. Electricity, phase line and neutral line all show the phase voltage; but there is no voltage indication when measuring with a voltmeter. According to the above situation, it can be determined that the neutral line is open in the single-phase power supply range.
A branch of the three-phase four-wire system has a zero-line disconnection fault. The specific manifestation is that within the power supply range of this branch line, some users' electric lights are not bright enough, fluorescent lamps cannot be started, the TV brightness is reduced, the image is reduced, and there is undervoltage protection. Appliances cannot be turned on or turned off automatically. In some users, the voltage is significantly increased, the lights are particularly bright, the fan speed of the bus processing machine is accelerated, and in serious cases, the lights or other electrical appliances are quickly burned out.
If the above situation occurs, it can be determined that the zero line of the branch is broken.
2. Prevention of zero line disconnection of busbar processing machine
For three-phase four-wire power supply, the single-phase load should be distributed as evenly as possible to maintain the balance of the three-phase load, strengthen the monitoring of the three-phase current, and adjust the imbalance in time. The neutral current cannot be greater than a quarter of the phase current, and the cross section of the neutral conductor cannot be less than one-half of the phase. The connection of the zero line should be firm and reliable. If aluminum wires are used for the lead-in and lead-out lines of the distribution transformer and distribution screen, copper-aluminum transition clips should be used, and inspection and maintenance should be strengthened, especially night inspections should be carried out to find sparks in the joints. processed in a timely manner.
It is strictly forbidden to install a fuse or a separate switch device on the neutral line of the three-phase four-wire system of the busbar processing machine. When disconnecting the three-phase four-wire line, the phase line should be disconnected first, and then the neutral line should be disconnected, and the wiring sequence should be reversed. In the event of a zero-line disconnection fault, the three-phase power supply should be cut off as soon as possible to reduce the accident hazard.
Only by strengthening the inspection and maintenance of the zero line and preventing problems before they occur, can the safe operation of the zero line be ensured and economic losses reduced.