Common Maintenance Failure Analysis

1. Machine operating mode and channel of choice:

    As the NCK function continuously strengthened, a NCK can complete multiple systems to complete the original work, which can have multiple channels, a channel rather with an independent NC, 840D can have up to 10 channels, each channel has its own zero over the set, tool compensation and R parameters, but the program area is shared, each channel has its own working methods, if the work of several channels have been the same, then this constitutes a method group. In the 840D, the way is way switch to select, access is key to W1 ... n to choose.

2. Tools and zero-bias

    Because different tools have different geometric shapes and geometry, while the program is subject to the workpiece size and therefore require compensation tool, each with its own knife, there is a corresponding geometric shape of the tool types, such as drills, milling cutters. Each knife can have more than a knife fill size, to D, to mark the

    Like with the tool, processing of different parts require different zero, so there is zero bias, in the 840D using G54 to G57 to select, if necessary, the number of zero-bias can also be used to expand the machine parameters.

3.840D system maintenance

* Maintenance of liquid crystal displays

     LCD display life of 30,000 hours. The backlight tube life is time 10000-20000 hours.

    Replacement backlight tube methods: a. Open the protective cover b. monitor the installation of loose screws, disconnect the power supply and display backlight control signal cable, remove the display c. replace the backlight tube d. above steps to install the opposite

* Replacement of the battery

    A total of 840 system, two batteries, one in MMC above, the main information to save CMOS, and its lifetime is at least ten years, it is generally no need to replace. Also a battery NCU BOX inside, and fans together, it is generally the life of three years or so, to save the NCK inside the programs and data, because of the protection of capacitor charging, you can replace the battery after the NCK full power, But time can not be more than 15 minutes

    This is the same as two battery models. Model: 6FC5247-0AA18-0AA0

(Note: the replacement battery it is best to make a few NCK and the PLC, data backup, Siemens 840C battery in the CSB board, must be the case of electricity in the system to replace!)

4.840D system data backup

    840D system data are many, including NCK data, PLC data and MMC data, which NCK and PLC data is by the battery to maintain, and it directly affects the loss of the normal operation of NC, while the data is stored in the MMC MMC hard disk (MMC103), or Flash EPROM inside (MMC100.2), which under normal circumstances, the loss of NC data only affect the display and input.

    System data backup methods are the following three

(1) backup to MMC's hard disk (only MMC103 adaptation), it is recommended best MMC, NCK and the PLC's data separately for backup, the file name is best to use the system default file name plus the date.

(2) backup to a floppy disk or through the RS232 port on the backup to an external computer.

(3) back to the NCK above the PCMCIA card, the card is an NC system, installed programs 8M of Flash EPROM card. It is about 5M or so of space can be used to store backup data. This feature is only in the MMC software version 5.0 and above to be used. Such data without a hard drive backup methods particularly suitable for the MMC100.2.

5. MMC103 file structure

MMC103 file structure

q MMC103's hardware is actually a band MPI (OPI) interface PC. Software is running on the WINDOWS operating system on a man-machine interface software. As the MMC version of the software not the same as its operation, the operating system are not the same, there are early WIN32, the mid-WIN95 and now WINNT, to run in WIN95 environment MMC Ver5.3 example shows the file structure MMC.

q MMC103 hard disk is divided into two partitions, C: drive and D: drive, where D is mainly used to store the hard disk drive and partition number of backup files, including several versions of the system brought about by MMC system backup, but also used to install software to use as a temporary storage area. C drive is mainly stored WINDOWS operation of the system files, MMC's system files, machine tool manufacturers developed a number of add-on software and user programs and data.

q C drive under the directory structure:

     C drive has the following directories under the main

     MMC2 mainly used to store system files, Siemens, Siemens, some of the standard configuration

Documents the existence of the directory, the directory the file is best not to modify the.

     Store Windows system files and Windows running on Windows environment and other

File

Add_on Siemens add-on products, such as remote diagnostics, etc.

OEM used to store tools on their own developed products.

USER storing the user's own configuration files, all with the standard configuration is not the same as the text

Pieces are stored in this directory, such as alarm settings for the service.

DH used to store data associated with the NCK, NCK its file structure and file

Structure, have a piece subdirectories, subdirectory workpiece main program, subroutine

A subdirectory, the standard fixed-cycle of a subdirectory, the user a fixed cycle of subdirectories and so on.

User alarm texts are generally the existence of the directory the following subdirectories inside MB.

These are the MMC103's file structure, in general, the user's own files are stored in the back of four directories inside, so MMC data backup is mainly a backup four directories and files.

Note: MMC earlier version of the user's own configuration files and system configuration files are stored in the system files directory.

MMC103 alarm server settings

MMC103 configuration are mostly. INI file for the suffix to achieve, such as knives library display, all kinds of operating mode password level required to operate, as well as alarm settings for the server, the following set up to alert the server to home shows the configuration file changes.

MMC is responsible for the display of alarm text, alarm text stored in MMC2 and DH the following subdirectories inside the MB, the file name format Alxx_xx.com, of which the first two XX said alarm contents of the text, followed by two XX said that the language of the text alert . For example ALP_UK.COM said yes PLC alarm text, language is English. And the relevant alarm display settings are stored in MBDDE.INI file.

These are the MMC103's file structure, in general, the user's own files are stored in the back of four directories inside, so MMC data backup is mainly a backup four directories and files.

    Note: MMC earlier version of the user's own configuration files and system configuration files are stored in the system files directory.

· MMC103 alarm server configuration

    MMC103 configuration are mostly. INI file for the suffix to achieve, such as knives library display, all kinds of operating mode password level required to operate, as well as alarm settings for the server, the following set up to alert the server to home shows the configuration file changes.

    MMC is responsible for the display of alarm text, alarm text stored in MMC2 and DH the following subdirectories inside the MB, the file name format Alxx_xx.com, of which the first two XX said alarm contents of the text, followed by two XX said that the language of the text alert . For example ALP_UK.COM said yes PLC alarm text, language is English. And the relevant alarm display settings are stored in MBDDE.INI file.

    Note: The user directory the following configuration files covering MMC2 directory configuration files. WINDOWS system configuration files of all the sum can not exceed 60KB.

6.611 series of drives and motors works

  * 611 series AC variable speed drive is a device that by controlling the power supply, the frequency of AC motor to achieve speed control purposes. The main part is from a DC to AC into the rectifier and the DC into an AC variable frequency inverter component.

611 module interface signals are the following groups:

q Power Interface

l U1 V1 W1 main control loop three-phase power input port

l X181 Power Supply input port, use is often associated with the main power supply shorted, and some systems the power to make machines work properly after the driver is also available for some time, the terminal voltage of 600V and P500 M500 terminals shorted, such as 600V discharge voltage can not be completed immediately, but also the maintenance of normal work-driven control panel for some time. P600M600 is a 600V DC voltage output terminal.

q Control Interface

l 64 control the enable input, the signal to all connected modules at the same time effective, the signal is removed, all the speed of the shaft for a given voltage is zero, axis with the greatest acceleration parking. After a certain time delay, cancel pulse enable

l 63-pulse enable input, the signal to all connected modules at the same time effective, the signal after the abolition of all the shaft power cancellation axis movement in the form of free parking.

l 48 main circuit relay, the signal off, the main control circuit power supply disconnect the main relay.

l 112 to debug or standard mode, the signal tends to be used in transmission-line debugging in general, on the receiving system, 24V.

l X121 module ready for signals and blocks the signal of overheating. No. ready signal and the module DIP switch settings on, when the S1.2 = ON, the module fails, ready to signal cancellation, and S1.2 = OFF, the module has failures and to make energy (63,64) signal cancellation, will be ready to cancel the signal, so when the replacement of the module to check the top of the module DIP switch settings, otherwise the module may not work correctly. All modules connected to motor overload and overheat alarm output will be triggered by overheating.

l NS1/NS2 closed the main relay enabled, only the signal is high, the main power relay is possible too. Relay the signal used to decide in closed-chain conditions.

l AS1/AS2 main relay state, the main relay the signal to reflect the closed state, the main relay is closed when high.

l 9/19/R 9 is a 24V output voltage, 19 is a 24V ground, R alarm reset signal for the module.

q Other Auxiliary Interface

l X351 device bus, for connecting the module behind the power to use.

l X141 voltage detection terminal, used for diagnostic and other purposes.

»7: P24, +24 V

»45: P15, +15 V

»44: N15,-15V

»10: N24,-24V

»15: M, 0V

q power supply module has six lights above, respectively, directed modules fault and working condition. Under normal circumstances, said green light enable signal loss (63 and 64), yellow light signals that the module is ready, when 600V DC voltage has reached the allowable value of the system work properly.

q 611D drive control module interface signals

        611D CNC control module and the system is mainly through a data bus connected to the basic there is not much of interface signals.

    X431: axis pulse enable, the signal is low, the shaft power to withdraw, generally the signal directly with the shorted 24V

    X432: BERO terminal, the interface used for BERO switch signal input port.

    X34, X35: analog output port, including two analog port (X1, X2) as a diagnostic test module, which can be used to track the amount of some figures, such as speed, voltage and current, etc. and to convert it into a 0 to 5V The analog voltage output, the specific output signal through the numerical control system selection, Ir analog output port is fixed and the output motor current in phase R analog value.

    X411: Motor encoder interface, input the motor encoder signals, as well as the motor thermistor, in which the motor thermistor value is through the socket 13 and 25 pin input, the thermal resistance at room temperature under 580 Europe , 155 degrees, more than 1200 in Europe, then control panel off the power and generate electrical power machines overheating alarm. (1PH7 motor temperature detection signal connected to the same 1FT6/1FK6 motor)

    X411: direct measurement of system input port, enter the direct position measurement signal, generally positive cosine voltage signals

    611D of the control panel of the speed loop and current loop inside the parameters set in the NCK, so no need to replace the control panel to reset the parameters.

The characteristics of servo motor

Because of the motion control, CNC machine tools demanding, and requires a good dynamic characteristics, a large speed range and accurate position control precision, and therefore it requires a special servo motor drive systems generally use the Siemens synchronous servo motor, spindle is Precision induction motor, its principles and general principles of the same squirrel-cage motors, synchronous servo motor and induction motors The biggest difference is not the same as the structure of the rotor. Synchronous motors have a staggered distribution of the rotor magnetic pole, thus the need for rotor position detection of the corresponding detection components, replacement parts, when these tests also need to re-adjust, the following is commonly used in three kinds of motor Siemens distinction:

· 1FT5 and 1FT6/1FK6 difference between motor

Both the motor is basically the same principle, but not the same as the structure and detection devices, 1FT5 AC servo motor used in the system, while 1FT6 motors are used in the digital servo system.

Stator winding structure is different, 1FT6 motor stator winding structure allows the motor current is much closer to being the cosine waveforms, 1FT5 motor tachometer generator is used to detect the speed of the motor with the sharing circle on the Hall element to detect the rotor relative position, and 1FT6 motor is to use a position encoder to detect motor speed, the motor encoder In addition to the conventional A, B, and R phase are cosine signals, there are two C phase and D phase is cosine signal to detect the rotor position.

    1FK6 1FT6 motors, like principles, only a little difference in the mechanical structure, 1FK6 more 1FT6 economy.

    Note: The replacement of the motor encoder should pay attention to the encoder zero position, replace the encoder to ensure that the replacement l before and after the rotor is not moving when the encoder wheel on a shell on the signs on signs and the relative position of the same, if the This relative position has changed only through the oscilloscope to adjust. Location of the encoder does not affect the motor is running, such as not running smoothly, the current is too large, and even affect the motor life.

7. Servo motor and spindle motor of the difference between

    Rotor structure is different, the spindle motor rotor and squirrel cage rotor motor, like the absence of magnetic poles, which does not require the corresponding rotor position detection signal, 1PH7 spindle motor encoder model ERN1381, 1FT6/1FK6 the motor encoder type To ERN1387, the main difference is that ERN1381 no additional C-phase and D believe that number, and therefore do not need to re-adjust the replacement of the encoder, ERN1387 can be used in 1PH motors, but in turn ERN1381 can not be used in the feed motor. Spindle motor power of a great general, and thus the motor structure of cooling demand is higher. Not the same scope of work, servo motor operates at the lowest speed and rated speed constant torque between the areas, while the spindle motor operates at rated speed and maximum speed constant power between the areas, because to achieve a great speed range of spindle the motor rated speed is generally very low

8. Common repair techniques

· ERN1387 Encoder Replacement Method

1. Unloading open motor rear cover, rear cover encoder

2. Release encoder mounting screws

3. Rotating rotor shaft, so that the encoder rotor encoder on the signs and marks on the shell overlap

4. Remove encoder, attention to handling the time out to make use of a special screw top to avoid damage to the encoder

5. Rotation of new encoders, so that the two signs coincide encoder

6. According to the above reverse order to install the encoder

    Note: In the process of installing the encoder, to ensure that the rotor different, otherwise they will lose the relative position of the rotor, if the loss of the relative position of the old motor will need to use the oscilloscope to adjust the installation position of the encoder, the new motor can be based on a sign of rotor shaft to adjust the encoder to determine the installation location, which can be mechanical adjustments, you can also adjust the drive parameters MD1016 to set an offset value, but the method can only be used in the 840D, through this method to adjust the motor change to other machine tool use may be due to the different driving parameters can not work properly.

* Zero adjustment

Adjustment steps are as follows: startup - → machine data - → Axis MD - → parameter adjustments: 34100 (axis coordinate value in the reference power) Amendment, if the change finished, now and in the original difference of 10mm, will be adjusted parameters 34100 to 10.

Can also 34090 (reference point offset) to modify: It is now zero difference with the original zero, the number.

* A simple power module detection method:

     As the power module is the main parts of high-power tubes, with the following methods can be broadly detect power tube is good or bad: multimeter hit resistance profile, with a multimeter is the table T received a power module DC voltage input terminals on the P600, to receive power tube The three-phase power output of U2, V2, W2, the resistance should be infinite at this time, exchange of the two tables pen multimeter, the resistance should be very small. The multimeter M600 received a pen on the table, repeat the above process, the results should be, and above just the opposite.

* Motor temperature alarm processing

    Motor which is equipped with thermal resistance of the signal through the signal cable back to the driver control panel inside, when the temperature reaches alarm value, the system to produce alarm, end feedback can be detected when the corresponding resistance value, the alarm if you need to shield , the 611D can be in the driving parameters MD1608 (the control panel of the 611A is a parameter MD64) to set a value of less than 100, you can mask the alarm, the method can only be used in diagnosis.

    Driver control panel connected encoder can be monitored, if there is an exception, then generate a corresponding alarm, 611A spindle control panel can be the parameter MD P-90 bit 2 set a screen of the alarm.

· 611D-driven V / F control

Sometimes, in order diagnostic, drivers need to be open-loop frequency control, this method can only be used for diagnostic purposes, and the speed can not be set too high. MD1014 is a set driving parameters namely, the open-loop frequency control

* Driven Optimization

    CNC driven by the current loop, velocity loop and position loop composed of the optimization in general from the inside and outer layers of optimization, but because of current loop parameters of the motor and power module model is established with the factory default parameter, the general does not require optimization, it is optimization optimize the speed of the first ring, and then you can optimize the position loop.

    Speed loop optimization, generally related to the speed loop gain and speed loop time constant, the speed loop time constant and gain the greater the lower the speed loop and more stable, but the accuracy and dynamic characteristics of the worse, in general, the speed loop time constant is located in 10ms, while the speed loop and speed loop gain adjustment in making the order is about to respond to a 20-40 overshoot.

    Position loop optimization involves the position loop gain and acceleration, before adjustment can reduce the acceleration value, and further increase the value of position loop gain to ensure the system is stable, and then increase the acceleration at an appropriate value, and to adapt the mechanical properties of machine tools, pay attention to the same group of interpolation axis position loop gain to be consistent, otherwise it will affect the machining accuracy.

* Axis shield deal

Sometimes the need for a single axis shield, concrete steps are as follows:

(1) in the corresponding axis parameters, the set MD13030 and MD13024 0

(2) in the driver configuration menu, find the corresponding module, set to "no active" can be, when the shaft on the virtual axis, the corresponding module and the motor can be removed, if you want to restore to The above parameters can be in the back to the original value.

    Axis load processing: Sometimes because of the need for machine tools should be dismantled or loading of the shaft, such as rotary indexing head, this time to plug the encoder and motor power outlet, Ran do not want the operator to change the above parameters, this time to PARKING temporary set to the shaft axis, the specific method is also reset the axis DB3X.DBX1.5 and 1.6 can