Fault of insufficient stroke of the brake core

Fault symptom: A GPS-2 imported elevator that has been in operation for 8 years. There is an irregular emergency stop phenomenon, which is not frequent. After an error, it can automatically level and open the door, and can continue to operate. The fault code given by the P1 board is EA, which means brake failure. But the opening and closing of the brake are normal, its resistance value is also normal (80-90 ohms), and the brake voltage is also normal.

Analysis and Solution: Preliminary judgment is that it is not a problem with the control cabinet, as if it were, it would be frequent. Upon inspection of the brake, it was found that the contact gap was too small, only 1.0mm, which is normally 2 ± 0.5mm. Then, when the brake core was disassembled, it was found that due to years of lack of maintenance, oil stains had accumulated in the core cavity, resulting in insufficient stroke and poor expansion and contraction of the core. When powered on, the electromagnetic force could not reach its maximum value. When the external voltage fluctuated or for other reasons, the core contracted and the brake contacts engaged, causing a malfunction. Thoroughly clean the iron core and cavity, readjust the stroke of the iron core to 1.5mm, open the brake clearance to 2.5mm, and the fault will no longer occur.

Summary: The iron core should be maintained regularly, at least once every 3 months. The brake and its contacts should be adjusted according to specifications and checked regularly. The fault in this case was caused by the resistance of oil stains, which resulted in insufficient magnetic force generated by the coil to balance the strong spring force of the brake, causing the brake contacts to instantly engage and transmit incorrect information to the main board, resulting in an emergency stop of the elevator.

2. Malfunctions caused by bow collision deformation

Fault phenomenon: A GPS-I imported elevator has been running for 7 years and rarely malfunctions. Later, due to wear and tear of the guide shoes, it was replaced and suddenly stopped near the top level. Then it was slowly dragged flat, and there was no problem running on the non top level. The P1 board did not display any errors.

Analysis and solution: It is definitely related to the top-level equipment. Since we have not reached the level position, we will not consider the limit and limit switches. First, check the 1USD and USR switches. When manually operated, they are connected normally. The distance between the pantograph and the switch is 62mm (standard is 58 ± 2mm), which is too large. Run slowly through 1USD, USR, and use a multimeter to measure the voltage of 1USD, USR, and 420. At the switch action point, the 48V voltage disappears. Indicates that its actions are normal. But when running on a fast train and colliding with the bow to sweep over the USR, there is a momentary appearance of voltage, which proves that when the elevator passes through the USR at high speed, the USR acts, but the USR signal disappears instantly, causing an emergency stop. Subsequently, a detailed inspection of the entire bow revealed a depression in the middle, measuring 30mm in length and bending inward by 10mm, which may have been bent before installation. The switch roller jumps instantly when running on its surface. After correcting the deformation of the collision bow and adjusting the distance from the switch to 56mm, the fault disappeared.

Summary: After replacing the guide shoes in the elevator car, it was unable to return to its original position, and coupled with deformation of the collision bow, it caused rare faults. Therefore, during maintenance, efforts should be made to ensure that the relevant dimensions do not change.

3. Weighing device malfunction

The GPS series elevator car weight signal is converted from the voltage value given by the differential transformer at the rope end to DA and transmitted to the CPU. Then, based on the car weight, the operating curve is given, so GPS elevators still have ideal comfort under different loads. If the rope head weighing device is not working properly and the weight value given is smaller than the set empty load value of the elevator car, the elevator will not be able to operate.

Fault symptoms: When the weighing device has a fault, it cannot operate without a driver, but it can operate in maintenance mode. After canceling the weighing function on the P1 board (adjusting the WGHO knob to 0), some drivers were able to operate, but there was no error display on the P1 board.

Analysis and solution: Generally, this type of malfunction is caused by debris between the brass sleeve of the rope head and the rope head rod, which hinders the operation of the copper sleeve. You can remove debris, but be careful not to add oil between the copper sleeve and the rod, as oil is more likely to accumulate. Then adjust the size of differential transformer spring to 37.5mm. Finally, it is necessary to rewrite the empty and half load data into the P1 board.

4. The problem with the group control cabinet caused two parallel elevators to malfunction

Mitsubishi GPS series elevators have a group control cabinet for two or more parallel elevators, which is specifically designed to handle additional functions such as fire return, emergency power operation, and stopping services.

Fault phenomenon: Two GPS-I elevators connected in parallel have been working normally, but suddenly both the fast and slow trains cannot run, but all peripheral circuits are normal after inspection.

Analysis and solution: The chance of two elevators experiencing the same fault at the same time is rare, so the group control part should be considered first. It was found that FERR and EMRR were not connected by electrical appliances, and then the coils were checked for no voltage. Finally, it was discovered that the CR fuse was burnt out. After replacement, everything was normal.

Summary: Different types of elevators have different design ideas. The above fault is due to a key circuit 420C in the group control part losing voltage, causing the NS (no service) function to take effect, resulting in all elevators being unable to operate. If you are not familiar with its characteristics, simply checking the fault from a single machine will not solve the problem.

What are the troubleshooting ideas and methods for Mitsubishi elevators?

Elevators are mainly composed of mechanical, traction circuit, and electrical control components. The drag system can also belong to the electrical system, so elevator faults can be divided into mechanical faults and electrical faults. When encountering a fault, the first step is to determine which system the fault belongs to, whether it is a mechanical system or an electrical system, then determine which part of which system the fault belongs to, and then determine which component or contact of which action part the fault comes from.

How to determine which system the fault comes from? The commonly used method is to first place the elevator in the "maintenance" working state, and then slowly move the elevator up or down at the level position of the car (in the machine room, car roof, or car operation) to determine. To ensure safety, it is necessary to first confirm that all hall doors must be closed and must not be opened again during maintenance operations! Because the elevator can move up or down during maintenance, the electrical control circuit is the simplest jog circuit. When the button is pressed, the elevator will run for how long. If the button is not pressed, the elevator will not move. The distance it needs to travel can be controlled freely, and the speed is very slow. The car running speed is less than 0.63m/s, so it is safer and easier for maintenance personnel to operate and locate the faulty part. This is an elevator function specially designed for maintenance personnel. The electric circuit has no other intermediate control links, it directly controls the elevator drive system. During the maintenance and operation of the elevator, maintenance personnel can observe whether there are any abnormal sounds or odors, and whether certain indicator signals are normal. As long as the elevator runs smoothly, it can be confirmed that the main mechanical system is fine, the main drive circuit in the electrical system is fine, and the fault comes from the control circuit of the electrical system. On the contrary, if the elevator cannot be operated by clicking, the fault will come from the mechanical system or main drive circuit of the elevator.

1、 Main drag system malfunction and its causes?

If it is confirmed that there is a fault in the main drag circuit during jog operation, that is, there is a fault in the main circuit, you can analyze the location of the fault from various links that make up the main circuit. Any AC/DC power supply circuit of a motor, including control circuits for various functions, must form a closed circuit for AC or DC current flow. If the current is blocked or diverted in any part of the circuit, it can cause a fault. The part where the current is blocked is the location of the fault. Of course, the power supply itself should be confirmed to be normal first, otherwise there is no current or the current size is inappropriate, which is also one of the parts that are prone to faults at different times. The basic components that make up the main circuit of any elevator are roughly the same: starting from the three-phase power supply, passing through the air switch, up or down AC contactor, speed controller, running contactor, thermal relay, and finally to the three-phase winding of the motor to form a three-phase AC current circuit. The speed regulation methods for different types of elevators are different, and the types of speed regulators are also different, which can be variable frequency speed regulation, AC voltage regulation speed regulation, DC voltage regulation speed regulation or soft starter. Of course, the matching motors are also different. Main circuit faults are also common and important faults in elevators.

Because the main drive system operates intermittently and frequently, after several years of elevator operation, the contactor contacts often experience oxidation, contact spring fatigue, poor contact, contact detachment, thermal breakdown or burning of the inverter module and thyristor, and motor bearing wear and tear. This is one of the quick ways to find faults, because any mechanical component has a certain lifespan, such as relays, contactors, micro switches, travel switches, buttons and other components, as well as frequently running components, such as the accompanying cables of the car, which often bend and move, there is a possibility of wire breakage.

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2、 Mechanical system failures and their fundamental causes

1. Malfunctions caused by loose connectors

During the long-term uninterrupted operation of elevators, fasteners may loosen or detach due to vibration and other reasons, causing mechanical displacement, detachment, or loss of original accuracy, resulting in wear and tear, damaging elevator components, and causing malfunctions. 

2. Malfunctions caused by natural wear and tear

Mechanical components will inevitably experience wear and tear during operation, and new components must be replaced when they reach a certain level of wear. Therefore, elevators must undergo major maintenance after a certain period of operation, replacing some vulnerable parts in advance. They cannot wait for faults to occur before updating, as this can cause accidents or unnecessary economic losses. As long as the elevator is adjusted and maintained in a timely manner during daily maintenance, it can operate normally. If the wear of sliding and rolling components cannot be detected and adjusted in a timely manner, it will accelerate the wear of the machinery, resulting in mechanical wear and failure, accidents or malfunctions. If the steel wire rope is worn to a certain extent, it must be replaced in a timely manner, otherwise it will cause major accidents. Various running bearings and other parts that are prone to wear must be replaced regularly. 

3. Malfunctions caused by lubrication system

The function of lubrication is to reduce friction, minimize wear, extend mechanical life, and also serve functions such as cooling, rust prevention, shock absorption, and buffering. If there is too little lubricating oil, poor quality, incorrect variety or improper lubrication, it can cause overheating, burns, shaft holding or damage to the mechanical parts.

4. Malfunctions caused by mechanical fatigue

Some mechanical components are often subjected to long-term stresses such as bending and shearing, which can cause mechanical fatigue and reduce mechanical strength and plasticity. Some components are subjected to force exceeding their strength limit, resulting in fracture and causing mechanical accidents or failures. If the steel wire rope is subjected to tensile stress, bending stress, wear and tear for a long time, and in more severe cases, uneven stress, one strand of the rope may be subjected to excessive force and break first, increasing the stress on the other strands of the rope, causing a chain reaction, and finally all the ropes will break, which may lead to a major accident. From the above analysis, it can be seen that as long as daily maintenance work is done well, relevant components are regularly lubricated and the condition of fasteners is checked, and the working clearance of machine parts is adjusted, mechanical system failures can be greatly reduced.

3、 Malfunctions and Causes of Electrical Control Systems

1. Malfunctions of automatic door opening and closing mechanism and door interlocking circuit

Because closing all hall and elevator doors is the primary condition for elevator operation, once the door interlock system malfunctions, the elevator cannot operate. This type of malfunction is often caused by poor contact or improper adjustment of various electrical components, including automatic door locks. 

2. Faults caused by insulation of electrical components

The insulation of electronic and electrical components will always cause insulation breakdown due to aging, failure, moisture or other reasons after long-term operation, resulting in open circuits or short circuits in the electrical system and causing elevator failures.

3. Faults caused by open or short circuits in the contacts of relays, contactors, switches, and other components

In control circuits composed of relays and contactors, faults often occur at the contacts of the relays. If the contacts pass through high currents or are eroded by arcs, they may become stuck and cause a short circuit. If the contacts are blocked by dust or the spring of the contacts loses elasticity, it may cause a circuit break. The circuit break or short circuit of the contacts will cause the control circuit of the elevator to fail, resulting in elevator faults

4. Malfunctions caused by electromagnetic interference

With the rapid development of computer technology, especially the widespread application of low-cost microcomputers in the control part of elevators, even using multi microcomputer control and serial communication to transmit call signals, the use of variable frequency and variable voltage (VVVF) speed control system in the drive part has become a popular standard design for elevators. In recent years, variable frequency door machines have also become fashionable, replacing the original DC door machines that used resistance speed control. The widespread application of microcomputers has increasingly high requirements for the reliability of elevator control systems composed of them, mainly in terms of anti-interference reliability. The various interferences encountered during elevator operation are mainly caused by external factors such as temperature, humidity, dust, vibration, impact, fluctuations in power supply voltage, current, and frequency, high-frequency interference generated by the inverter itself, operator errors, and load changes. Under the influence of these interferences, elevators will produce errors and malfunctions. Elevator electromagnetic interference mainly has the following three forms:

(1) Power supply noise: It mainly enters the system from the power supply and power supply incoming lines (including ground wires).

Especially when the system shares power with other frequently changing large loads, it can generate power noise interference. When the power lead is long, the voltage drop and induced potential during transmission can also cause noise interference, affecting the normal operation of the system. Power noise can cause the microcomputer to lose some or most of its information, resulting in errors or misoperations.

(2) Noise invading from the input line. When there is a common issue between the input line and its own system or other systems

When there is a common ground wire, this noise will enter, and sometimes even if isolation measures are taken, it will still be affected by electromagnetic induction coupled with the input line. If the input signal is very small, it can easily cause errors and misoperations in the system.

(3) Electrostatic noise: It is caused by friction, and the static electricity generated by friction is very small, but the voltage can reach tens of thousands of volts.

The materials provided by the IEEE Reliability Physics Symposium indicate that a person walking on a blanket can be charged up to 39KV, and a person working at a workbench can also be charged up to 3KV. Therefore, when a person with high potential comes into contact with a computer board, the charges on the human body discharge into the system, causing rapid discharge current and noise, affecting system operation, and even causing damage to electronic components. In response to the above situation, anti-interference measures must be taken, and the anti-interference measures themselves should be correct and reliable, otherwise elevator failures may occur.

(4) Malfunctions caused by damage or improper adjustment of electrical and electronic components: The electrical system of elevators, especially the control circuit, has a complex structure. Once an accident occurs, it is necessary to quickly eliminate the fault. Experience alone is not enough. This requires maintenance personnel to master the working principle of electrical control circuits and the working process of control links, clarify the interrelationships and functions between various electrical and electronic components, and understand the installation position of each electrical component. Only in this way can the occurrence point of the fault be accurately determined and quickly eliminated. On this basis, summarizing and applying the practical work experience of others and oneself can be beneficial for quickly troubleshooting and reducing losses, because some faults that occur during operation still have patterns.

4、 Methods for finding electrical faults:

When the elevator control circuit malfunctions, the first thing to do is to ask, look, listen, and hear, so as to have a clear idea. The so-called asking refers to asking the operator or the person who reported the fault about the phenomenon at the time of the malfunction, and checking whether any adjustments or component replacements were made before the malfunction occurred; The so-called 'look' refers to observing whether each component is working properly, whether various signal indications of the control circuit are correct, and whether the appearance color of electrical components has changed; The so-called listening refers to whether there is any abnormal sound when the circuit is working; The so-called smell, whether there is any abnormal odor in the circuit components. After completing the above work, the following methods can be used to find faults in the electrical control circuit.

1. Sequential inspection method:

Elevators operate according to a certain program, and each operation goes through a cycle of layer selection, orientation, door closing, starting, running, speed change, leveling, and door opening. Each step is called a working process, and each working process has an independent control circuit. The program inspection method is to confirm the specific control link where the fault occurs, so that the direction of troubleshooting is clear, and targeted troubleshooting is important. This method is not only applicable to electrical control systems with contacts, but also to contactless control systems such as PC control systems or microcontroller control systems.

2. Static resistance measurement method:

The static resistance method is to use a multimeter to measure the resistance of a circuit in the resistance range when there is a power outage, because any electronic component is composed of a PN structure, and its forward and reverse resistance values are different. Any electrical component also has a certain resistance value. The circuit or switch connected to the electrical component has a resistance value that is either zero or infinite. Therefore, measuring their resistance value to determine whether they meet the specified requirements can determine whether they are good or bad. This method can also be used to check the quality of an electronic circuit for faults, and it is relatively safe.

3. Potential measurement method:

When the above method cannot determine the location of the fault, the potential at both ends of each electronic or electrical component can be measured under power on, because under normal working conditions, the potential at each point on the current closed-loop circuit is constant. The so-called potential at each point refers to the different potential to ground of each point on the circuit component, and there is a certain size requirement. The current flows from high potential to low potential. Measuring the potential on the electronic and electrical components in the direction of the current should follow this rule. Therefore, using a multimeter to measure whether the potential at the relevant point on the control circuit meets the specified value can determine the location of the fault, and then determine why the current value change is caused by incorrect power supply, circuit break, or component damage. The sentence is:.

4. Short circuit method:

The control circuit is composed of switches, relays, and contactor contacts. When suspecting a fault in one or some contacts, the contact can be short circuited with a wire. If the fault disappears when powered on, it proves that the judgment is correct and the electrical component is broken. However, it should be remembered that after testing the fault point, the short-circuit wire should be immediately removed, and it is not allowed to use short-circuit wires to replace switches or switch contacts. The short-circuit method is mainly used to find breakpoints in electrical logic circuits, and sometimes it can also be used to measure electronic circuit faults. Below is an introduction to the short-circuit method for finding faults in door lock circuits.

Two people are on the top of the car, using the maintenance point to operate the elevator. They use the maintenance speed to reach a certain floor, open the automatic door lock protection plate, connect one end of the short wire to Line 01, and check whether the contact is normal on the other end. When the short wire touches Point B and C to close, but does not touch Point A and C to close, it indicates that the door lock contact is disconnected. Release the short wire, repair the contact or replace the door lock switch. However, using the short-circuit method can only find the breakpoint of the logical relationship contact between "and", and cannot check whether the relay coil is short circuited, otherwise it will burn out the power supply.

5. Circuit breaking method:

There may also be some special faults in the control circuit, such as the elevator stopping when there is no internal selection or external call indication. This indicates that some contacts in the circuit have been short circuited. The best way to find such faults is to use the circuit breaker method, which involves disconnecting the suspected faulty contacts. If the fault disappears, it means that the judgment is correct. The circuit breaking method is mainly used for fault points with logical relationships between "and".

6. Alternative method:

According to the above method, if the fault is found to be at a certain point or on a certain circuit board, the component or circuit board that is considered to have the problem can be removed and replaced with a new or confirmed fault free component or circuit board. If the fault disappears, it is considered that the judgment is correct. On the contrary, it is necessary to continue searching. Often, maintenance personnel have spare parts for vulnerable components or important electronic boards. Once there is a fault, they can immediately replace it with a new one to solve the problem. The faulty part can be brought back and slowly searched and repaired, which is also a fast troubleshooting method.

7. Experience based troubleshooting method:

In order to achieve rapid troubleshooting, in addition to constantly summarizing our own practical experience, we also need to constantly learn from the practical experience of others. Practical experience often leads to a certain regularity in the summary of elevator failures. Some experiences are important lessons that have been hard-earned, and we should pay more attention to them. Often, these experiences can help us quickly troubleshoot and reduce accidents and losses. Strictly speaking, elevator accidents should be prevented, which is the responsibility of our maintenance personnel. This time we are writing this book to collect the maintenance and troubleshooting experience of many peers at home and abroad, in order to improve the technical level of our company's installation and maintenance staff, as well as enhance the company's service level and reputation.

8. Basic ideas for troubleshooting electrical systems:

The electrical control system sometimes has complex faults, and now elevators are controlled by microcomputers, with software and hardware intertwined. When encountering faults, don't be nervous first, and when troubleshooting, adhere to the principles of starting with the easy and then the difficult, starting with the external and then the internal, considering comprehensively, and making associations.

A common fault in elevator operation is caused by poor contact of switch contacts. Therefore, when judging the fault, the external circuit and power supply should be checked first based on the fault and the display of the indicator lights inside the cabinet, including door contacts, safety circuits, AC/DC power supply, etc. As long as you are familiar with the circuit, you can quickly solve it by following the clues.

Some faults are not as simple and intuitive as relay circuits. Many protection links of PC elevators are hidden in their software and hardware systems, and their faults and causes are strictly corresponding to the results and conditions. When looking for faults, they are systematically associated and speculated on the relationship between them, and the doubts are eliminated one by one until the fault is eliminated.

There is a problem with the door panel

The door motor board adopts three-phase control with voltage and speed regulation, and one of the phases continues to maintain a small torque through resistance to prevent the door from being opened after closing. This is why the Mitsubishi SPVF ladder always outputs a door closing signal during operation. However, because of this, the door motor board works for a long time and has high requirements for electronic components. The door position signal is sampled through a grating disk. The position of the grating disk is very important. Although it may seem dead, it can actually be fine tuned. In short, during the switching process, it is necessary to see the process of the LED lights turning on, off, on, off, and on. Otherwise, if the elevator door looks normal and the terminal motor is still running, over time, the door motor board will be ruined. The door panel is easy to repair unless it is completely submerged and cannot be used again. Have you seen those red modules? Usually, it's because this thing is broken, and replacing it will be okay.

Protect oneself as soon as it runs

Generally, elevators have a fault detection system that automatically protects themselves during operation, indicating that faults are only detected during operation, such as elevator overcurrent, encoder no output, mismatched drag data, etc. Due to the inability of previous elevators to remember faults, self protection faults occur every time power is cut off. For this fault, we first identify the cause of self-protection. Without repairing the machine, we first look at the encoder. The output of the encoder has 2.5V AC power when the motor rotates, and the voltage should be less than 1VDC when it stops. If the encoder is fine and the external wiring is normal, it may be caused by overcurrent, or it may be a real overcurrent output, such as motor overcurrent, elevator overload, or a problem with the current detection unit (DC-CT). We can detect the bias voltage of CT on the E1 board. If it is not normal, we need to adjust the OFS potentiometer of DC-CT. How to adjust it is recorded in the installation and commissioning manual of SPVF

The door closed halfway and then opened again

This is a very simple question, listed here because this type of fault occurs too frequently. Generally, the connection wire of the safety contact board on the door will be broken or short circuited due to the frequent movement of the door. This causes the safety contact board wiring to be on and off as the door moves, resulting in the door partially closing and then opening again.

The floor indicator does not flash during the write operation

In debugging and maintenance, we often need to write the floor height, which is actually the number of floor pulses and the location of deceleration points. If the floor indicator does not flash or flashes first and then stops flashing during writing, data cannot be written in. This is usually due to abnormal door zone signals and forced deceleration. The one-way forced deceleration signal has the function of forcing the floor to be 1. The door zone is the key to sampling floor height. Some overseas Mitsubishi door zone signals have two, one pushing the relay and the other inputting into the computer. Do not assume that the door zone signal is normal just because the DZ relay is activated or the DZ light on the computer board is on.

Nine How to cancel the internal selection of a certain floor in the GPS-2 elevator?

Solution: Change CC2

Ten A Mitsubishi SP-VV (A) elevator operates normally, but occasionally only opens 10-30 centimeters after leveling. Then the floor indicator flashes, the PLC scan stops, and it can be restored after power failure. Sometimes it can last for several days, and recently it can only be used for a few hours Recently, malfunctions have become increasingly frequent. May I ask where the problems are with various experts?? Also, sometimes 1DV displays fault 35. What does it mean? Is there a problem with the encoder?

Solution: Display 35, indicating that the running speed cannot keep up with the set speed.

You can remove the encoder casing and inspect it with a soft cloth. It's best to replace the encoder, but encoders in West Germany are rare.

The PLC did not scan, it is internal self-protection.

Eleven The malfunction of the two GPS-3s is somewhat similar to yours. Mine is two parallel connected devices, one of which automatically lifts the ladder every three floors. The basement goes down on its own even when no one calls, but when it reaches independence, it won't. The outbound call tower flashes like a red light after a while. Finally, we pulled out the faulty parallel communication cable from the cable tray and swapped the sockets, and it disappeared. We now suspect that there may be a problem with that cable

Twelve A Mitsubishi SPVF elevator experienced a door mechanism that did not rotate (unable to open or close, but the door motor was energized and unable to move). The control cabinet received a door closing signal, and the elevator was able to move after manually closing the door. The voltage of the three wires of the door motor was checked to be 56, 28, and 28, and the voltage of the door motor switch was 105

Solution: The cause of the malfunction is that one wire of a socket on the control cabinet is not properly connected (pin problem), which is the UK socket

Thirteen Mitsubishi SPVV-A elevator has experienced a roof failure in the past two to three days. Fault phenomenon: The elevator has 10 floors and a speed of 1.75m/s. I observed and registered the 7th and 10th floors in the computer room, and the elevator kept showing that the 1st floor remained unchanged until it reached the top.

Solution: This malfunction is caused by dust on the encoder encoder disc

Fourteen A GPS-II elevator makes a "buzzing" sound when the elevator decelerates at each floor, which is unpleasant to hear, especially when reaching the top floor. It is normal when descending

Solution: One of the bearings on the worm gear is broken, which cannot be seen with the naked eye. Only after replacing it can we know. This elevator traction machine has four bearings, and the one next to the coupling is broken. The model is 6311Z

Fifteen Mitsubishi GPS-2 (EF - unable to restart) crashes, elevator crashes at random floor level position, no floor display, unable to call in, car lighting fan has no power, control screen fault code (EF - unable to restart), safety circuit, weighing device, parallel connection, machine room temperature and heat dissipation are all normal. The faults occur during the low usage period of the elevator in the middle of the night and early morning, with a frequency of 1-2 times per day. It can be used normally for a period of time after emergency stop or maintenance reset, and sometimes it crashes continuously after pulling power and sending electricity

Solution: Check if the flat sensor is faulty

Sixteen Mitsubishi HOPE fault seeking help, a Mitsubishi HOPE elevator car lighting is not working, LCM relay is closed. If the LCM relay is not closed, the elevator car lighting is bright. After checking the circuit, there is no problem, but the problem has not been investigated

Solution: There is a problem with the sleep function of the door machine board. Just disconnect the relay wire and let it be powered on. However, there is no sleep function anymore. Let's replace the board! That thing often malfunctions like this

Seventeen

Mitsubishi GPS elevators are the mainstream products of Mitsubishi in recent years, with various models including GPS, GPS-2, GPS-CR, GPS-3, etc

Dov

Main circuit live light

twenty-nine

Safety circuit

eighty-nine

Automatic or in operation

Dz

Door area indicator light

41dg

Door closing light

sixty

Automatic state

Pp

Phase failure (ACR insurance) light

Up

Run on top

Dn

Run down

twenty-one

Open door command

twenty-two

Door closing instruction

Dwdt

Secondary computer operation

Cwdt

Main computer running

1. Stuage empty: When no fault occurs, it will be displayed when entering the fault display. 2. A-NEG<A-MAX DECORATING/A-NEG The range determined is smaller than the range given by INSTALLATION/A-MAX. After the electric motor cools down, it can automatically resume operation. 7. V1... V3 V1 speed is smaller than V2 or V2 degree is smaller than V1, The control screen did not receive any feedback signal. 10. NO STOPING Despite the brake being closed, the mechanical brake contactor "MB" elevator did not stop. 11. RV1 or RV2 simultaneously generated running signals in two directions. 12. RV1/RV2 MISS without setting direction. 13. tacho drop out There is no speed feedback signal when the elevator starts or runs. 15-19. The minimum allowable value has been reached, and the corresponding option content should be increased. 20. EPROM ERROR controller content is incorrect, contact ZIEHL-ABEGG company. 21. All content in EPROM cleared controller has been erased and needs to be rewritten by the manufacturer. This information was only updated when the control screen software was replaced by different new numbers. Display. 22-25. The maximum allowable value has been reached, The value of the corresponding option content should be reduced. 26.v3<1.5v-nen travel/v3 value may not exceed 1.5 times the INSTALLATION/V-NEN value. 27! SWITCH OFF！  The control screen must be turned off for a short time. 28. SHORT TRAVEL OFF? Point out that short-range operation was not achieved. Input the erased "V1" value before inputting "V-ZE3". 29. The connection between the POWER STAGE motor and the POWER STAGE (IDV interface) is still in an open state during testing. 30. V-Z<V-3 TRAVELING/V-Z option value is smaller than the TRAVELING/V-3 value. 31. V-Z TOO SMART has reached the limit line. 32. STOP INPUT! Although the content of a certain option is being changed, the elevator is still running after receiving the operation command. 33. POWER STAGE temperature monitoring on the TEMP-COLLER IDV is overheated. 34. DRIVE WITH BREAK shutdown (mechanical brake has been closed with "MB" action). 35. N-PROG>>N-REAL elevator fails to run at the given speed. 36. N-PROG<<N-REAL actual speed is much higher than the set speed. 37. MTR STILL TURNS motor is still rotating, although mechanical brake has been applied (controlled by relay "MB"). 38. False ROT FILD power line is not connected to the phase, and the corresponding two phase lines on the control board and power supply need to be swapped. Please pay attention to the same phase connection on the two hard boards. 39.PARA-CHANGE? The option content has been changed during runtime. 40. MOTOR-CHANGE? During operation, the second motor was replaced

18 Mitsubishi SP-VF is seeking help. I have an elevator that broke down while it was working normally. All the internal selection buttons are on, saying 'The elevator goes layer by layer', 'Stop on the first floor', and 'The floor it stopped on just now lights up again'. The elevator keeps going like this

Solution: Move the car control panel to the machine room and try it out. If everything is normal, I will press the control panel back into the car to solve the problem. It is estimated that the interference was caused by poor contact of the serial interface of the car control panel.

Nineteen Mitsubishi door machine malfunction seeking help, a Mitsubishi SPVF elevator experienced a door machine not rotating (unable to open or close, but the door motor had power supply, just unable to move), and the control cabinet had a door closing signal. After manually closing the door, the elevator could move. The voltage of the three wires of the door motor was checked to be 56, 28, and 28, and the voltage of the door machine switch was 105. The door machine board was swapped with other elevators, and the board was in good condition

Solution: After a detailed inspection, it was found that the door machine was missing phase.

Twenty Mitsubishi GPS-II fault assistance, our unit has a Mitsubishi GPS-II elevator, the fault phenomenon is: the elevator has an emergency stop during operation, and then automatically levels. We found that the SWDT indicator light on the P1 board is not on, and then the elevator cannot run. After the power was restored, the elevator automatically programmed and then returned to normal

Solution: Restore normal operation after replacing the P1 board.

twenty-one. Mitsubishi SPVL seeks help. Recently, an 18 story SPVL elevator has been experiencing a common problem of burning high-power transistors. The temperature fuse is good, the drive board has been replaced, and the large capacitor has also been replaced. However, the elevator has been running for several days and still experiences this situation

Solution: Normal after replacing the E1 board.

twenty-two Mitsubishi SP-VF fault assistance, seeking help for Mitsubishi SP-VF elevator 3rd floor 3rd station. Fault status. The elevator stops on the first floor but is not on the same level and is elevated. Not displayed. Connect the safety circuit, an overload sound will immediately sound inside the elevator car, and the machine room will display the 1st floor flashing continuously. The elevator just won't go.

Solution: The safety relay is broken. The door machine belt of the rear door is also severely worn. There is a strong burnt smell.

twenty-three A Mitsubishi VVVF elevator used to be normal, but since March this year, it has frequently stopped abruptly during operation. When faults occur, even the floor display is turned off, and the car lighting is normal. Usually, such faults occur once every five or six days. When the fault occurs, the position of the elevator is not regular, and there is no regularity in the direction of operation. The power supply has been checked and the power cables and switches have been replaced. According to the debugging outline, various voltages are measured and meet the requirements, and the safety circuit is also normal. However, this fault has not been resolved.

Solution: The output pins on the P1 E1 W1 board have been burned once and the problem has not occurred again.

twenty-four Seeking advice on GPS2 door machine, adjust a GPS2 elevator door machine. After adjusting the speed of opening and closing the door, run it several times or lock the elevator and then open it again

The speed will change and cannot be fixed no matter what

Solution: The operating distance between the car door lock switch and the photoelectric switch is 9 and 5, respectively

twenty-five. A Mitsubishi GPS-2 passenger elevator with 32 floors, no stops between the 1st and 5th floors, and two maintenance doors. During normal use, users have reported that sometimes the elevator suddenly stops when running from the 6th to the 7th floor, and then levels back to the 1st floor, and everything is normal. Sometimes, the above phenomenon occurs again on the 7th or 8th floor. It is located on the nearest level and occurs around 6 pm every day. The safety circuits such as door locks, switches, maintenance door switches, door balls, door knives, etc. have been checked multiple times. The P1 board and door motor board have been replaced, but the fault still exists. The user's opinion is very high. Note that there are three parallel elevators on this construction site, and this one has a problem. The issue with the 380V power supply should be ruled out

Solution: The problem has been resolved and the weighing has been redone. No issues have been found in the past few days!

twenty-six

Hope's elevator suddenly stopped after running for a period of time. The cause of the malfunction is that there is no display, the indicator lights inside the car are not on, the buttons are not working, and there is an error in the transmission of the seven segment digital display EB from the machine room to the car. I found out through multiple inquiries that there is a problem with the SBC-C chip inside the car, but it has been replaced and is functioning normally.

Fault phenomenon: Elevator control cabinet maintenance. Upward elevator does not start/Service center

Mitsubishi SP VF ladder type

The cause analysis can be seen from the maintenance up control circuit diagram 2-20 that when the automatic maintenance relay 60 is placed in the maintenance position, the D-S diode is damaged, or the up button UP is not pressed properly or damaged, the 89 relay does not work, the main contactor and the brake contactor LB cannot be powered, and the elevator will not start.

Troubleshooting: If TB24 has a voltage of+125V and there is no voltage at both ends of the 89 safety circuit relay coil, it indicates a fault in the circuit. After power failure, measure the normally closed point of relay 60 using resistance mode. When the up button is pressed, the two contacts conduct, and it is suspected that the D-S diode is damaged. Measure the open circuit of the diode with a multimeter in the resistance range, replace the protective diode D-S, and activate the 89th relay. Press the maintenance up button, and the elevator will move up normally.

Fault phenomenon: The elevator car roof is under maintenance and the up going elevator is not running/Service center

If the contact of the automatic maintenance switch or the up button is not in good contact, it will cause the elevator to stop running.

The troubleshooting method is to set the automatic maintenance switch to the maintenance position, press the up button UP, and have another person cooperate in the machine room to observe whether D89 lights up. If D89 remains unlit, it indicates that there is a fault in the 89 relay circuit. Check that the wiring of the car roof junction box is normal, and that the automatic maintenance switch and button switch are functioning properly. Go to the computer room to check that the wiring of relay 89 is not loose, and the measurement coil is normal without any open circuit phenomenon. Finally, tighten the wiring terminals on the W1 board again, press the plug again, and then turn on the power to move upwards normally. The wire contacts from relay 89 to W1 board are loose and have poor contact.

Fault phenomenon: The elevator does not open the door in any state, and the service center does not close the door

Mitsubishi SP VF ladder type

The reason analysis shows that the elevator cannot open or close the door in both automatic and maintenance states, indicating that there may be problems with the main circuit and control circuit of the door opening and closing motor. The door motor of the Mitsubishi elevator is three-phase AC 110V. If the power transformer is damaged and there is no 110V output, the door motor will not operate. The door opening and closing signal is controlled by the W1 board. If W1 does not output a door opening and closing signal, it will not open or close the door.

Troubleshooting method: Check that the 110V power supply is normal, confirm that the three windings of the door motor are symmetrical, and that the door motor has no faults. When the manual contactor operates, the main contact is in good contact. Finally, it was suspected that the thermal relay may have malfunctioned. It was observed that the thermal relay had indeed acted before without resetting. After the microcomputer W1 received a thermal relay action signal, it caused the door to not close in any state. It may be due to accidental overcurrent, causing the door motor thermal relay to activate. After resetting the thermal relay, the door switch is normal

Fault phenomenon: The elevator has poor leveling accuracy on each floor outside the terminal station/service center

Mitsubishi SP VF ladder type

Reason analysis: SP-VF Mitsubishi elevator is controlled by forced speed change switches at the upper and lower terminal stations, with good leveling accuracy, indicating that the deceleration switch position is installed correctly and the deceleration speed mode is correct. The speed change and deceleration points of the middle layers are achieved by a simulated elevator composed of a microcomputer combined with a rotary encoder. When simulating an elevator, it needs to start one step ahead of the actual elevator (by giving an advance amount). Its purpose is to detect where the target floor is, that is, to stop at the floor to be responded to first. At the same time as the simulated elevator stops at the destination floor, it sends a deceleration signal. When the elevator slows down to the destination floor according to the deceleration mode, the PAD leveling switch signal is obtained, causing the elevator to stop leveling. So the leveling accuracy of the intermediate floors outside the terminal station determines the accuracy of the time advance and deceleration speed mode of the simulated elevator given by the microcomputer, which is equivalent to the accuracy of the deceleration point position before the elevator leveling.

Troubleshooting methods like this belong to microcomputer software debugging problems. The software debugging personnel of the manufacturer can modify and debug the advance time and deceleration speed mode of the simulated elevator to solve the problem.

Fault phenomenon: Upward elevator does not operate during in car maintenance/Service center

Mitsubishi SP VF ladder type

During the maintenance of the elevator car, when the automatic maintenance switch was set to "maintenance", the 60 relay lost power, causing the 89 safety circuit relay to lose power. The elevator could not start automatically and was in manual jog operation due to the loss of microcomputer control. After the 89 safety circuit relay is energized by inching, it enables the LB brake contactor and main contactor to be energized, realizing the inching operation of the elevator. When conducting maintenance inside the elevator, press the up button for maintenance inside the elevator, and the 89 relay will be powered on, allowing the elevator to move up slowly. If there is a fault at any point of the car roof up button, D-S diode component, or 89 relay in the upward circuit, the upward movement cannot be achieved. The upward direction signal is controlled by SSU. If there is a fault in the direction control circuit, that is, when the UP button is pressed, the SSU point does not receive a high potential and cannot achieve upward jog operation.

Troubleshooting method: Check and measure the up button UP inside the car for maintenance, ensure that the diode component D-S is conducting, and there is no fault with the 89 relay. The D-S component of the direction control circuit is also conducting without any faults. So where did the malfunction occur? Suspected that the car roof maintenance switch was not reset to the "automatic" state, as the maintenance personnel had just come down from the car roof due to a malfunction. Upon inspection of the car roof, it was confirmed that the automatic maintenance switch was still in the "maintenance" state. As shown in the diagram, the maintenance circuit inside the car cannot receive a+125V control power supply at this time, so it is impossible to jog upwards. After setting the automatic maintenance switch on the top of the car to the "automatic" position, the upward operation of the car during maintenance is normal. A fault like this should be taught a lesson, and what has been done must be restored. For example, when troubleshooting, sometimes it is necessary to short-circuit some circuits to verify whether there is a fault. After that, do not forget to remove the short-circuit wire in a timely manner, otherwise it will cause significant losses and major accidents.

Fault phenomenon: When the three-phase power supply of the elevator is normal, there is a phase loss protection/service center

Mitsubishi SP VF ladder type

The reason analysis shows that the phase loss protection circuit in Figure 2-24 is different from other elevator forms. From transformers TR01 and TR02 → three-phase AC 100V → three-phase rectifier R-ACR →+125V (79-00) The value of the 125V power supply reflects whether the three-phase power supply is missing phase, which is monitored by the electronic circuit E1 board. When any phase is missing, the+125V is greatly reduced. The E1 electronic board sends a phase loss signal to the microcomputer logic operation, and the motor cannot start running. Any fault in this circuit will generate an erroneous phase loss signal.

The troubleshooting method was to check that the incoming line 380 of the power grid was correct, and the+125V was also correct. It was confirmed that there was a breakpoint phenomenon during the transmission of+125V. The VA-03, UA-03, and UB-10 plugs were all plugged in again, and after feeling firmly plugged in, the power was restored and the elevator ran normally.

Fault phenomenon: The safety switches are all in the normal position, but the safety circuit relay is not powered, and the elevator does not start/service center

Mitsubishi SP VF ladder type

The cause analysis is shown in Figure 2-19. Although all safety switches in the shaft are normal, the automatic maintenance relay is not working or damaged, or there is no power supply. The 60 normally open point is not working, and the 89 safety circuit relay is also not working.

After inspection, it was found that the 60 automatic maintenance relay did not receive power, but it was actually a minor fault. As the control cabinet maintenance relay had just been repaired and forgot to place it in the "automatic" position in a timely manner, the 60 relay would not receive power, and the 89 relay would not work. Place the control cabinet maintenance relay in the "automatic" position, and the fault will disappear. Sometimes, due to busy work, if it was not originally a fault, it could be caused by human error. This phenomenon should be noted.