Weak current College】 【Mitsubishi common failures and resource collection (2) --- Power By】 【China power house network.

<br> III. electrical control system causes a fault and <br> 1. automatic switch on the door and the door interlock circuit failure <br> Because close all Hall, car door is the most important condition of elevator operation, door interlock system .failure elevator cannot run. Such a failure is by including automatic door locks, electrical components-contact bad or improper adjustments.  <br> 2. electrical components caused by the failure of insulation <br> Electronic and electrical components are insulated in long- .running after the Association by aging, failure, damp or other causes insulation breakdown, resulting in the electrical system of the circuit breaker or short-circuit faults caused by elevator. <br> 3, relays, contactors, switches, and other components-contact .circuit breaker or a short circuit caused by the fault <br> By relay, contactor control circuit of the fault occurred in the relay contacts, if the contact is through high current or contact arc erosion, is adhesive will cause a short circuit. If the .contact is dust blocking or contact Reed elasticity will cause circuit breaker, breaker or short-circuit the contacts of the elevator control link circuit failure, so that the lift fails. <br> 4. electromagnetic interference caused by the fault <br> With the .rapid development of computer technology, in particular, the dramatically lower the cost of a micro-computer widely to the elevator control part, even with microprocessor control and serial communication transmission callsbased, driven partly by vvvf (VVVF) elevator speed system has become a popular .standard design in recent years has also become a fashion frequency crane, replace the original DC resistance speed door. The wide use of microcomputer on the composition of the elevator control system reliability increasingly demanding, mainly anti-jamming of reliability. Elevator operation encountered various disturbance ., main external factors: temperature, humidity, dust, vibration, shock, power supply voltage, electric current, the frequency of the wave, the inverter itself produces high-frequency interference, the operator's mistake and load changes, etc. The role of the .interference, the elevator will generate an error and fault, Elevator electromagnetic interference in the following three forms: <br> (1) power supply noise: it was mainly from the power supply and power cord (including Earth) intrusion into the system. < .br> Especially when the system and other regular movements of large load sharing power supplies will produce power noise interference. When the power inlet is long, the transfer process occurred in drop, EMF will generate noise interference effects system working, power supply noise can cause .computer missing part or most of the information, an error or malfunction. <br> (2) from the input noise line intrusion. When the input line and its systems or other systems exist for public <br> Total ground, exploits this noise, .sometimes even with quarantine measures, there will still be subject to the input line phase coupling of electromagnetic induction, if the input signal is very low hours, extremely easy to make the system-generated errors and malfunction. <br> (3) static: .it is caused by the friction, friction-generated static, is very small but the voltage up to tens of thousands of volts. <br> IEEE reliability Physics Symposium materials show that walking on the carpet people live up to the next in the Workbench 39KV .persons charged or up to 3KV, so to have a high potential for human contact computer Board, the human body's charge to the system, the rapid discharge current cause noise, affects the system work, or even cause damage to electronic components. In response to .the above conditions must be in anti-jamming measure, anti-jamming measure itself should be correct, reliable, or else will have elevators. <br> (4) electric electronic damage or relocation of failures caused by wrong: elevator electrical system, in .particular the control circuit, complex structures, in the event of an accident, to quickly troubleshoot and experience alone is not enough, this requires the maintenance personnel must master electrical control circuit working principles and control aspect of the work process, clear all electrical and electronic .components relate to each other and their role in understanding the various electrical components of the installation location, the only way to accurately determine the failure points and quickly be excluded. On this basis to others and your own practical work experience to summarize and applications, to .rapidly troubleshoot and reduce losses will be useful because some migration xingzhong failures or regular. <br>? <br> IV. electrical fault find method: <br> When the elevator control circuit failure, the first question to ask, see, hear, .smell, be aware that the so-called asked, is asking the actor or report the failure of the phenomenon of failure occurs, the query failure before it has made any adjustments or replacing components; the so-called, is the observation of each part .is working correctly, see the control circuit of various signal indicates whether correct, electrical components, such as whether to change the appearance of colors; the so-called listen, listen when circuit abnormal sound; the so-called smell, smell the circuit elements .whether there are abnormal odour. Upon completion of the work, you can use the following methods to find electrical control circuit failure. <br> 1, sequence checking method: <br> Elevator is a program to run every time you run all through the .selected layer, directional, closed, start, run, change speed, leveling, opening the door of the cycle, where each step is called a working link for each work session, there is an independent control circuit. Program inspection method is to confirm that .the failure of specific control links appearing on which, in the direction of troubleshooting is clear, focused on troubleshooting is important. This method applies not only to have contact with electrical control system, also applies to the contactless control system, such as the PC control .system or microprocessor control system. <br> 2. static resistance measurement method: <br> Static resistance method is in power, multimeter resistance measurement circuit resistance stalls are normal, because any one of the electronic components are a PN structure, its forward and .backward resistance values are different, no electrical components also have a certain resistance, connected to the electrical components of the line or switch, resistor value not equal to zero is infinity, measuring their resistance value size meets the requirements can judge. Check an electronic circuit .is good or bad for any failures can also be used with this method, and more secure. <br> 3. potential measurement method: <br> This method cannot determine which parts can be powered with measuring various electronic or electrical components, because of .both potential in work situations, current-loop circuit points potential is considerable, the so-called points potential refers to various points on the circuit elements on ground potential is different, and there is a certain size requirements, current flows from the high potential, .low-voltage current direction to measurement of electronic and electrical components on the potential size should be consistent with the law, so the multimeter measuring control circuit for points of potential compliance values, you can determine where the point of failure, and then determine the reason .why the changes caused by current value is incorrect, or the power supply circuit breaker, or component is damaged. <br> 4 short circuit method: <br> Control-link circuit are switch or relay, contactor contacts. When you suspect that one .or more contact points have a failure, you can traverse the contact shorted, power to prove fault disappears, the judgement, the electrical components is bad. But remember, when you find the point of failure when finished testing should immediately removed short wiring, wiring .with short is not permitted in place of the switch or switches-contact. Short-circuit method is mainly used to find the electric circuit of breakpoint logical relationships, of course, sometimes the measurement circuit faults can also use this method. The following describes the .short-circuit method to find lock circuit failures. <br> By two people in the car top, used to move the elevator maintenance, use and repair speed runs to a floor, turn on automatic door lock protection plate, with short wiring a terminating .01 line at one end and check whether the normal contacts, when short wiring to touch the point b, and C pick-up A point C does not touch the pick-up, door-lock contacts described has disconnected. Release short wiring, repair .or replace the door lock switch contacts. But used a short connection, you can only find "and" logical relations contacts, but cannot find the relay coil is shorted, otherwise it will burn out the power supply. <br> 5. circuit breaker .method: <br> Control circuit also may be some special failure, such as the elevator does not have internal or external call indicates when it stops, etc. This shows that some contact is in circuit shorted, find such a failure is the best way .is the circuit breaker method, it is suspected that the contact points generated fault, if fault breaks away, explains judgment correctly. Circuit breaker method is used primarily for "and" logical relationship point of failure. <br> 6. alternative method: < .br> In the light of the above methods, found fault for a point or a block circuit board, you can take that component or circuit board removed, use new or confirm no failure of a component or circuit board in place, if the failure is .considered to determine the right away. Instead you need to continue to find, often maintenance personnel on the vulnerability of the components or important electronic boards are available in spare parts, once there is a failure immediately put on a piece that solves the problem, faulty .parts back then slowly find repair, it is also a quick troubleshooting method. <br> 7, experience troubleshooting method: <br> In order to be able to achieve rapid troubleshooting, in addition to constantly sum up their own practical experiences, to learn .other people's experience, practical experience often make the elevator has a certain pattern of failure by summing up, some experience with sweat to important lessons, we should pay more attention to. Often these experience allows us to quickly troubleshoot and reduce accidents and losses. Of .course, strictly speaking it should eliminate the elevator accident, this is our maintenance staff should have the responsibility. This time we write this book is a collection of domestic and foreign many colleagues repair troubleshooting experience, to improve our company's installation and maintenance staff skill levels .while increasing the level of the company's services and reputation. <br> 8. electrical system troubleshooting basic ideas: <br> Electrical control systems sometimes fail more complex plus now lift are computer-controlled, cross-hardware and software together, experiencing trouble first .thoughts don't be nervous, troubleshooting at the insist: increasing difficulty, after first-in, an integrated consideration, associations. <br> Elevator in more failure is caused by poor contact switch contact of faulted, so judgment fails should be based on .failure and cabinet led display, the first part of the external lines, power supply, check that the door contact, safety circuits, AC-DC power supplies, etc., as long as you are familiar with the circuit, this allows you to solve .very quickly. <br> Some faults are not as relay lines so straightforward, PC Protection link in the elevator of many are implicit in it hardware and software system, its failures and reason as results and conditions is strictly correspond to find fault in an orderly .manner on their relationship with Lenovo and exclude doubt guess, one by one until the troubleshooting. <br>.