Anti-misoperation locking device - Solutions - Huaqiang Electronic Network

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First, the design and manufacturing quality is inferior As mentioned above, there are many types of anti-misoperation locking devices, as long as the quality can be guaranteed to play a blocking role. However, due to the following problems in design and manufacture, it is often impossible to block.
(l) The products provided by the manufacturer do not fully comply with the actual situation on site. Because the designers are not familiar with the situation on site, and lack of experience, the products designed and manufactured not only can not meet the "five-proof" functional requirements, and often have many defects. This problem is more prominent with the microcomputer locking device. Taking the line-side grounding knife lock as an example, in order to prevent the grounding of the live grounding knife when the line is energized, the line must be inspected before the consultation. The grounding knife gate is allowed to be input only after confirming that the line is dead by the power inspection. Since the designer did not understand this very critical operation, it was omitted in the program, resulting in a unit with such a device, and a grounded and grounded gate accident occurred.
(2) The product quality is inferior and cannot be used after installation. Some switch factories have defrauded the manufacture of anti-missing devices to service companies (other names may also be used) consisting of family members and some retired or laid-off workers. Most of the people in these companies have not undergone rigorous technical training and do not have the required level of craftsmanship. In addition to the lack of quality management and strict factory inspection mechanisms, the quality of the manufactured products is inferior. For example, two famous switch factories, the electromagnetic locks brought to the circuit breakers, not only the rough process, the auxiliary contacts are not in place, often fail, and can not be protected from moisture, and soon after being put into operation, they are scrapped due to serious corrosion.
Second, the installation and commissioning is not standardized (1) Missing project. If the substation with the program lockout device is installed, the position where the guard key is placed is not added to the control panel during installation. As a result, No. 1 key has no place to put. Some units plug it into the guard hole of the switchgear, which does not function as a lock; on the analog board, it cannot mark the use of the temporary ground wire.
(2) The lock and the key do not fully match. If some keys are inserted, they cannot be pulled out; some microcomputer locking devices cause deformation of the lock seat during installation, and the operation is not working.
(3) Some substations adopt mechanical locking and locking methods, which cannot meet the requirements of “five defenses”.
Third, there are problems in the operation and maintenance work (1) The operating personnel cannot correctly use the anti-misoperation locking device. The operating personnel (including the length of the value) are mostly ignorant of the performance, function, requirements and usage of the anti-missing device, and thus many problems arise in use. The specific performance is as follows: in the red and green card locking device, the red and green card is equivalent to the unlocking key; the position of the first key in the program locking device is the key of the whole locking device; the program used in the computer locking device is very strict, no Allow free to cross, unlock the key is not allowed to use, etc. These basic knowledge is not clear to many operators. Therefore, in use, the following problems often occur:
1) The red and green cards fell to the ground and no one was jealous. In the red and green card for the locking device, the red and green cards are equivalent to unlocking the key. There is a substation that uses such a locking device. In one operation, it is impossible to drop the red and green cards of the circuit breaker to the ground. The value is long enough to try to take the cards of other switch devices and replace them.
2) The placement of the first key in the program locking device is the key to the complete locking device. It should normally be placed in the appropriate position on the analog board. Some substations have inserted them into the No. 1 lock hole of the switchgear, so that they do not lock.
For substations that use a microcomputer lockout device, some computer keys are not often charged. Due to under-charging, the suction is insufficient, causing the electric code lock or the mechanical code lock to be unlocked.
4) Unlock the key unattended. Some substations put the unlocking key and other keys together or throw them on the table. The operator can carry it with you and use it at will.
(2) No one is responsible for maintenance work, and no defects are handled. If the anti-missing mechanical lock is broken, the chain that isolates the closing lock is detached, and the computer key is broken, etc., no one is responsible for repair or replacement.
The following suggestions are made for the above issues:
(1) Power plants that have not been equipped with anti-misoperation locking devices must formulate practical plans and install them as soon as possible. For new or expanded power generation projects, the anti-misoperation locking device shall be put into operation at the same time as the main equipment. When using a computer monitoring system, remote and local operations should have an electrical lockout function.
(2) The design and manufacture of the anti-misoperation locking device must ensure that the “five-proof” function is complete, in line with the actual, and reliable performance. Especially for the design of the microcomputer anti-misoperation locking device, the operating unit should explain the various possible operating modes (including special operation modes) in the power system and the problems that should be paid attention to during the switching operation to the designer. And carefully review and approve its design plans and drawings.
(3) Manufacturers that have the ability to produce anti-missing locking devices and have passed the inspection and qualified by the quality inspection agencies at the ministerial level should be selected. Even a well-known manufacturer must state the quality standards and requirements and responsibilities when signing a contract. When necessary, key components should also be sent to the manufacturing plant for supervision. It is necessary to prevent products with unqualified quality from entering the production site. Products that have been installed but cannot be used in poor quality, such as the electromagnetic collar produced by a switch factory, should be modified, replaced or repaired by the relevant manufacturer. Before this treatment, it is recommended to install a general copper lock for locking, but it should be fully functional. Some products manufactured in the early stage of the factory have some parts with poor quality and should be contacted and replaced in time.
(4) During the installation process, the operating unit shall be assigned with the experienced operational technical personnel. For the circuit breaker or the disconnecting circuit of the isolating switch, the auxiliary contact of the circuit breaker or the isolating switch should be used directly. In the handover acceptance, it should also organize experienced operators to participate in the test, one by one, the test is good. Some tests, such as the empty contact test, some debuggers are too troublesome to do, must adhere to the instructions. With the program lock, if the first key is left unattended, it can be hung on the corresponding switch device on the analog board.
(5) The microcomputer anti-misoperation locking device has the advantages of high reliability, simple operation and maintenance, small installation and debugging workload, moderate investment, strong adaptability, etc., and is currently widely used in power systems. However, the microcomputer locking device also has a serious disadvantage, that is, once the AC power is lost, it is possible to unlock the entire process when the operation is closed. This makes the operation very complicated and prone to errors. For this reason, it is recommended to install an uninterruptible power supply UPS in the transmitter and substation that uses the microcomputer to prevent mis-locking.
(6) In the operation and maintenance, it is recommended to do the following work:
1) Combine the actual operation rules and maintenance procedures of the anti-misoperation locking device, strengthen the operation, maintenance management of the anti-misoperation locking device, and ensure the normal operation of the installed anti-misoperation locking device.
2) Conduct a technical training on the electric operation personnel for the anti-misoperation locking device, and understand that the principle, performance, structure and operation procedure of the anti-misoperation locking device can be understood. It will be familiar with and will correctly use the anti-misoperation locking device as a necessary condition for assessing electrical operators.
3) The patrol inspection maintenance and fault handling of the anti-misoperation locking device should be included in the on-site operation rules in order to facilitate the operation and implementation of the operation personnel; after the anti-misoperation locking device is put into operation, the suspension must be approved by the leader. Feel free to disable.
4) In the biotechnology department of the power plant, there should be a technician responsible for the management of the anti-missing device. In the maintenance and repair class, someone should be specifically responsible for the maintenance of the anti-misoperation locking device, so that defects can be dealt with in a timely manner.
5) Strengthen the management of the unlocking key, and propose to establish a system for the use and storage of the unlocking key. It is clearly stated that only the fault occurs during the operation, and the person in charge or the station manager can find out the cause, confirm the failure of the lockout device, or use it when the accident handling and maintenance work is needed. When it must be used, it must be approved by the relevant leaders. Enhanced monitoring should be performed when unlocking.
Some units take the method of unlocking the key in the envelope, clearly specifying the method of opening the key and allowing the opening of the leader, and establishing a record book for the reason for the unlocking, and conducting regular analysis and assessment. It not only prevents the operator from unlocking at will, but also improves the integrity of the anti-missing device and enhances the responsibility of the maintenance personnel for the maintenance of the device. This is desirable.