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Showing posts from November, 2016

6RA70 equipment, in the direction of the times police F030!

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A company 6RA70 equipment, in the direction of the times police F030!
Problem supplement:
My equipment is reversible rolling mill, each time the alarm F030 is the time to change, and sometimes just change the alarm, and sometimes to go for a while and then alarm, alarm reset after the normal work!

Best answer
Fault F030:
Detection of current loop optimization, the need to re optimize the current loop. Activate the "trace" function by using the fault to find the cause of the fault.
If the fault value is 1 or 2, if necessary, can be set U580 = 4, a detailed description of the U580 see instructions or document: http://support.automation.siemens.com/WW/view/en/19868341 value is 3 (such as fault current greater than r072.02 250%) may be due to the four quadrant braking device in voltage sag. Check motor brush commutation without ring fire, you can refer to the maintenance of the old motor. Note: fault F030 can only use U580 = 0 shield (can not use P820 shield).

Damage cause of s7300 analog input module

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S7300 analog input module (331-7KB02-0AB0 6ES7) 3 years of bad 2, the input signal 4-20mA, consult the module is easy to damage the reason?

Best answer
Reference: analog quantity module damage
Http://www.ad.siemens.com.cn/service/answer/solution.aspx? Q_ID=63278&cid=1029?

MRES switch problem

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MRES switch how the operation will clear the data and procedures PLC400.

Best answer
1 memory card inserted in the bottom of the CPU. CPU requires the machine to reset (LED STOP lamp slowly flashing).
2 switch the switch to MRES and keep it there (about 9 seconds) until the LED STOP light continues to shine.
3 in the next 3 seconds must be switched off, and once again to MRES. LED STOP lights flashing in the process of removing.
Specific operation reference:
"Introduction to the S7-300CPU memory card and the use of memory cards (updated version)" to understand: (2007.12.28)
Http://www.ad.siemens.com.cn/download/searchResult.aspx? SearchText=A0097?
Introduction to <S7-400CPU memory and memory card usage (2006.09.22) > download:
Http://www.ad.siemens.com.cn/download/searchResult.aspx? SearchText=A0053?
"MMC card data read and write (updated version) (2008.01.17) > Download
Http://www.ad.siemens.com.cn/download/searchResult.aspx? SearchText=A0113?

WINCC no landing window

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This is based on the WINCC PCS7 landing, the installation of the CEMAT version number is 7.1SP1, the selection of the 007 library. Before the project is a good, normal use. For some reason, today I will reinstall the computer system, in accordance with the step, CEMAT also re installed, but when the project is running WINCC, found that even the landing window are not, also below the toolbar also shows only a part, do not know what was the problem, reply.
Picture Description: 1, user management 2, PROJECT OS is also normal 3, landing interface

Best answer
Operating system service is not running, reinstall the system, do not ghost, complete installation

S7-400PLC program lost

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The S7-400PLC program under what conditions will be lost, if the PLC power supply and power supply immediately, will not have lost PLC program.

Best answer
1, if the PLC power supply, power supply immediately, will cause the PLC program is lost?
If there is no backup battery or flash memory card (prior backup), will cause the loss of the PLC program.
2, the relevant S7-400 data retention mechanism:
See "CPU S7-400 and 318-2 CPU CPU data retention" download:
Http://support.automation.siemens.com/CN/llisapi.dll? Func=cslib.csinfo&amp;objId=23750626&amp;load=treecontent&amp;lang=zh&amp;siteid=cseus&amp;aktprim=0&amp;objaction=csview&amp;extranet=standard&amp;viewreg=CN?
"The use of CPU S7300/400 backup battery" download:
Http://www.ad.siemens.com.cn/download/docMessage.aspx? ID=1283&amp;loginID=&amp;srno=&amp;sendtime=?
or
Http://www.ad.siemens.com.cn/download/SearchResult.aspx? SearchText=A0071?
See <S7-400CPU memory pre…

PLC STOP switch problem

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Can not use the program or other settings to prohibit the use of ST0P outside the S7-400PLC or MRES switches.

Best answer
Can not. This can only be considered from the system or external equipment, such as:
1, the development of relevant operating system
2, to the PLC cabinet lock

WINCC status display problem

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Through the 400PLC control of a WINCC status display, but in WICC do not see the connection variables of him and PLC, is indeed WICC internal variables seen in WICC, this is what he shows the status of the PLC through what way, is not through C script or VB script to achieve, how should the specific find?

Best answer
WINCC comes with the tool which has a diagnosis channel tool, if WinCC and PLC communication is normal, then show green. Methods of operation: start - SIMATIC - WINCC - TOOLS - diagnosis channel
Reference: "PLC link WinCC, the same variable appear in different states"
Http://www.ad.siemens.com.cn/service/answer/solution.aspx? Q_ID=69517&amp;cid=1032?
"WinCC and PLC communication status display"
Http://www.ad.siemens.com.cn/club/bbs/post.aspx? B_id=4&amp;a_id=608320&amp;s_id=41&amp;num=5?

SIEMENS PID parameter settings why the same procedure as the PID parameters, but the output value of the change is not the same

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The master station set up a PID control valve is P=5 I =5 D=0 control is stable, can be output to the maximum and minimum values, but also I have a program through my 200 and Mudbus communications, from the station of PID is the same as the PID parameter value is written from the master station through the station, but is P=80 I =5 D=0 from the station to output to the maximum and minimum values, or PID reaction is very slow

Best answer
Because PID is required to detect the amount of feedback in real time ah! Is not entirely determined by your parameters, but also to see the feedback of the data in order to achieve closed loop ah! You two are not the same system, the same parameters, and finally the results are not the same as normal ah!

SIMATIC S7-CP PtP Param V5.1

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S7-CP PtP Param V5.1 SIMATIC how to install, how I can not hold up
Best answer 1, I would like to ask how to properly install PtP Param V5.1 Sp8 CP: Http://www.ad.siemens.com.cn/service/answer/solution.aspx? Q_ID=68387&amp;cid=1029? 2, see the answers to similar questions: Http://www.automation.siemens.com.cn/Service/answer/solution.aspx? Q_ID=97625&amp;cid=1027?

SMART SR60 S7-200 how to use the PWM function

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Relay type output can use PWM function?

Best answer
1, Smart specification, as shown in figure 1.
2, pulse width modulation (PWM) output cycle. If the time is millisecond range allowed is 2 to 65535; if the time is microseconds, range allowed is 10 to 65535.
PWM belong to the pulse output, can not be used to see your output frequency high or low! Since you want to use PWM want to output frequency is not low, then it is not recommended to use the relay type output PWM function!

How to determine the direction of movement of the Q0_0_MoveAbsolute

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Q0_0_MoveAbsolute is not like Q0_0_Movevelocity in the direction of the input, then it is how to determine the direction of motion

Best answer
This is the absolute position of the directive, directly through the next set of positive and negative to determine the positive and negative

How to install SIMATIC automation license

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I installed V5.5+sp2 STEP7 after the start, said not to install license SIMATIC automation, installed when I installed the V5.1+sp1+upd3, but I do not see my software

Best answer
The authorization manager will when installing the STEP7 software installed at the same time, in the beginning of your program -- --STEP7 find the authorization manager manually start a lot when the authorization manager cannot be used because the installed software conflicts, led to the authorization manager cannot use.

How to add comments in the function block attribute

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Is the function or function block object properties in the "notes" how to add notes, I want to customize some commonly used function block in the database, if a long time do not know how to use, you want to add a comment.

Problem supplement:
I don't want to ask how to address assignment comment block, I asked the right click, then click the "object" can see some block attribute, but the "notes" column is gray, you cannot edit the display only, my intention is to leave comments on this. It is the comment of the block rather than the address, the variable.
Best answer
Problem supplement:
Notes
If you have already assigned a comment to the block, the comment is displayed here.
I can!
FC block in the properties of the notes, how to write it?
You only need to open the FC function, fill in the title bar you want to annotate the content, and then save.
At this point you open the FC property to the comment bar is the desired content.

Plcs7-200 analog module EM231 can measure the frequency of the signal it

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Plcs7-200 analog module EM231 can measure the frequency of the signal it

Best answer
The analog module can measure the voltage (0-10V, 0-5V) and current (0-20mA, 4-20mA) signal, if your frequency signal through the circuit (such as inverter frequency signal into a current signal output) into the current or voltage signal, then can be measured: for example EM231 0~100HZ corresponding to 0~20mA

Cpu222cn can be followed by two analog modules EM231cn?

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Cpu222cn can be followed by two analog module EM231cn? The CPU connection is connected to EM231, then EM231 is connected with a EM231, then EM231 CP receiving module, which can meet, know to say ah, recently has been working on this problem, the programming software can only detect two analog modules, while CP can not be detected, if removed a simulation module, CP can be detected, this is why?
Best answer Cpu222cn can only bring up to two modules (including the CP module), for 224 of the bar

How to read data with WinCC

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Own a WINCC, used to read several temperature S7 program online, the online diagnosis tool software WinCC, two green checkmark above, below the red lightflashing. A WinCC online now. Just read the temperature on the interface and otherfeatures are not, should be inserted into the input field is, right? (This step please little) Please understand.
The best answer
Yes, your diagnosis indicates that the WinCC and PLC communications properly, you need to build variable connection in connection with the WinCC PLC address of the temperature, and then insert the WinCC screens IO domain, IO IO domain in the domain properties into the output field, WinCC and connection of an external variable (address of the temperature of the corresponding PLC). Last run WinCC can.

How to call S7-300 function block

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Front fork function blocks in the data reference is not called if they are able to call what should call
The best answer
Front fork features may indeed have not been called, or be called indirectly.
Indirect calls, such as UC FC [#TEMP3] depending on the #TEMP3 value calls different FC.
If it does not call directly in ladder diagrams can be added to the program.

Graph language SS S1

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Graph Action S1 and s two directives in what's the difference?



The best answer
S=Set

SP1 wincc7.0 stuck

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Wincc7.0 SP1 when you deactivate "alarm system" stuck not moving
1. project integration
2. the path of Chinese characters
3. alarm: configuration operator records
Two. OS project editor: Select message configuration and complete configuration only difference?



The best answer
You have I encountered this situation, there was an acceptance of the WINCC project, but now I want to use OS project editor build. phenomena like the PCS7 results screen layout as the same. Later deleted images with @, which is generated by OS Editor, and a manually created picture set as the initial screen. Then run just fine. OS project editor is not recommended, more trouble, though they can build as in PCS7 picture layout

CP341 hangs on ET200M, how to software distribution?

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Now in a redundant system, CPU414-4H ET200M module using PROFIBUS communication, but need to use Modbus communication, I can see document said ET200M CP341 Modbus master, then practice again to field devices, hardware configuration was introduced, but at the time of software, still called the FC functions directly?



The best answer
Use consistent and in 300.
CP341 PTP driver is first needed, PTP driver installs CP340/341 function blocks required for programming, PTP driver supplied with the CP341 module, can also be downloaded from the following link: http://support.automation.siemens.com/CN/view/zh/27013524 CP341 order the MODBUS MODBUS communications need to Dangle the hardware dog Dangle with MODBUS master/slave driver, from Siemens download, http://support.automation.siemens.com/CN/view/zh/27774018

How to use CPU224XP to control the bar code printer and scanning gun

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Use CPU224XP control bar code printer and scanner, and requires induction to a product, PLC automatically generates an automatic increase bar code and automatically check for the right bar code scanner, what should I do, what hardware it needs background

The best answer
First of all you need 2 communication ports do free traffic and bar code printer, andscanner communication
Because 224XP traffic levels are 485, you should determine whether your printer interface is 485, as most are 232 interface of the scanner, if it is 232, you need to buy a232 to 485 module and DP communication port connection PLC,

Can the WINCC6,0 system be shared with a BA monitoring system on a computer?

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Used to be 2 computers, a DDC system control computer, a PLC and is related withWINCC6.0 computer, BA monitor computer access communication through OPC Protocol; now combined in one computer, can achieve? Will there be conflict database?
Also, WINCC6.0 as the server, can be more than one computer at the same time as the client access?



The best answer
As the server can be accessed by multiple clients.
And on a computer, they should be able to. Databases do not conflict.

3TK2983-0BB4 product manual

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Getting 3TK2983-0BB4 product brochures,



The best answer
To look at here:
http://support.automation.siemens.com/WW/llisapi.dll?func=ll&objId=22926038&nodeid0=20358221&prodLstObjId=22926038&subtype=133400&lang=de&siteid=cseus&aktprim=0& objaction=csviewtd&extranet=standard&viewreg=WW&selectedLang;22926038=1&switchLang;22926038;6.x=1&langex=zh

how to SIEMENS 300PLC connect with the servo motor

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Companies have been using the Siemens 300PLC a connection before Mitsubishi servo motor. I 300PLC put the FM module. Servo servo controller. Because we are theowners of reason. Not the manufacturer. At that time I was responsible for some simple maintenance and troubleshooting. What are other people doing. But I feel that I still do not understand. I want to ask the friend can understand about the theory,wiring, hardware, which modules are used, there is a program, which features blocksused, and servo control parameters and the settings of the above?



The best answer



1, the details in the following document:
See the FM357-2 multi-axis positioning template getting started download:
http://www.ad.siemens.com.cn/download/docMessage.aspx?ID=3513&loginID=&srno=&sendtime=
2, look at this, S110 products:
http://www2.ad.siemens.com.cn/download/HTML/Download2.aspx? EntryId= 785f7e386c980935d586cd2146cb809ba4b9712f01643cf3b92ed95df916c1bd58e4505854130119962222e7f6ee3b136caed2a8512a9361239…

How to use the 300plc as master and 200PLC as slave station of DP group

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Using a 300plc CPU 314C-2DP now call the shots and do 3 sets of 200plc CPU is 226DP network from a station group. DP communication module uses EM277. now have a problem, when I try with a 200plc network, there is no problem, but not more than two. I configured the hardware download into 300plc (OB withoutprogramming), the SF light red, and push the switch to the RUN, but forced toSTOP. Don't know what to do?



The best answer
3 EM277 address is not the same, and with 300 addresses are not the same. EM277code consistent with the configuration of your address.
SF lights, can be viewed online access to the Diagnostics buffer failure cause

How to communicate MPI line with MPI port

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CP5711 with MPI cable plug in MPI, PG/PC automatically State, the properties startnetwork detection connection into a DP can detect communication. Then a DP lineconnecting 5711 with the MPI port, test, ask why? MPI line DP 4 more than 5 feet, are here for a reason. Venue is the desk.
Supplementary question:
PG/PC select 5711 automatic State, do not need to set parameters and properties start network detection can detect MPI/DP, rate, and so on. Even CPU MPI with MPI thread is now no, Profibus cable. Two wire DP will do. Really do not understand.
The best answer
CP5711 card options and settings in Step7 software
CP5711, the first note cards establish communication with the CPU, you have to use MPI or Profibus cable as the cable CPU and CP5711 card connecting cable. open "SIMATIC Manager", click "Options" in the drop down menu to find the "SetPG/PC Interface ..."
(A) If select and CPU connected of is MPI interface, at S7ONLINE (STEP7)-> for CP5711 card (MPI), …

How to rewrite before upload TP270-10 touch screen

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Touch-screen TP270-10 backup file in PSD format what software do I use to rewriteWINCC2008 read-only can be converted to HMI HMI format PSD format file formathow do you rewrite TP270 touch-screen uploaded back

Supplementary question:
New editors can do WINCC2008 written with WINCC HMI HMI format is the formatcan do what to touch-screen communication

The best answer
PSD-format file is a compiled file, you can only download to new touch-screen, butcannot be modified.

How to rewrite the TP270-10 touch-screen file backup

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Now Wincc2008B version but only read out touch-screen HMI format files are PSD format from touch-screen of the PSD file format how to rewrite and then pass into the touch screen now only backup to restore in the touch-screen how to change out

The best answer
Only install the touch screen SD card and return is enabled when the program downloaded in the original function, can only upload HMI-formatted file that you can edit. Or you can upload PSD is not editable.

S7300 hardware configuration and module power consumption calculation method

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With S7300 313C of CPU added IM365 again extended a machine frame. 313C itself since with 24DI16DO and the simulation entered output 5AI/2AO, see Configuration Manual above CPU behind can placed 8 a module, wants to will about, CPU itself integrated of I/O surface to except did? is regardless of is what CPU Hou end are can placed 8 a module, (manual Shang CPU right shall not installation eight a above of module (SM, and FM, and CP). The cumulative power of the module installed on the rack at S7-300 on the backplane bus must not exceed 1.2 a. ) Cumulative power don't know what refers all 5V power consumption on a rack? don't know understand,digital input not available 5V power consumption, only digital outputs and analog inputs and outputs can be found to the 5V power consumption values, use the IM365 extended time frame 1 module can only receive signals; the cumulative current load limits
1.2 a, Bay 1 maximum current of 0.8 a, understandable Bay 0 1.2A Bay 1 maximum can only b…

Causes and prevention methods of electric line fire

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Electrical fire caused by line failure is common for many reasons, mainly below for everyone to resolve the main cause of electric lines caught fire and prevention measures.

A main cause of the fire, electrical lines:

(A) short circuit. So-called short circuit is the circuit of communication two wires touch each other, current does not pass through the line of electrical equipment, and form a loop. Due to the resistance of the wire itself is relatively small, if only throughthe wires of the circuit current will increase rapidly, dozens of times, hundreds of times times greater than normal. Such a large current through a thin wire, due to greater resistance, generated more heat, in a very short period of time the wire has reached thousands of degrees Celsius temperature enough to ignite nearby flammablematerial, causing fire. Is caused by short circuit due to transmission lines used for too long, insulation aging, cracking, loss of insulation, two dash lines; or because thewiring, wire &…

How to detect the leakage of the line?

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General Household circuit, leakage power line zero leakage, if the said method, see:
Electrical lines because of the long service life, it will cause the insulation, insulatorsdamaged, damp or worn insulation layer, produced on the line leakage. In total by one meter on the switch, remove the load and connect the load switch.
If ammeter pointer swings, description line leakage. Cut off the line;
If ammeter pointer does not change between the wire and the earth leakage;
If ammeter pointer back to zero, indicating between FireWire and zero leakage;
If the ammeter indicates smaller, but not zero, it indicates that the line with the zeroline, the line of fire and earth leakage. Remove the branch fuse or operation gate, ammeter, indicates the same leakage indicates that bus; the ammeter indicates zero instructions shunt leakage; the ammeter indicates small, but not zero, it indicates that bus and the shunt leakage. Fixed leakage after the tap, then pull off the lineswitch. When snap to a switch…

Wire and cable specifications

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Wire and cable products used in power system are mainly bare overhead wires, bus (bus), power cable (plastic cable, oil paper power cable (basically replace the plastic power cables), rubber cables, overhead insulated cables), branch cable (instead of part of the bus), electric wire with electrical equipment and power equipment wire and cable etc..

1, model, name:

RV copper core vinyl chloride insulated connection cable (wire)
AVR copper core PE insulated flat flexible cable (wire)
RVB copper core PVC flat wire connection
RVS copper core PVC stranded wire
RVV copper core PVC insulated and sheathed flexible cable with circular connection
ARVV tin copper conductor PVC insulated and sheathed flat flexible cable
RVVB copper conductor PVC insulated and sheathed flat flexible cable
RV105 copper core heat resistant 105oC PVC insulated PVC insulated flexible cable
AF205AFS250AFP250 silver plated PVC fluorine plastic insulated high temperature 60oC~250oC soft wire connection

2, the meaning of …

Types of high voltage switchgear and analysis of common faults

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High-voltage switch cabinet is very important in electrical power system equipment.Switchgear condition deterioration is one power causes a system failure. So, what are the common faults of high voltage switch cabinet?


(A) outdoor-and indoor


From the placement of high-voltage switch cabinet, can be divided into both outdoor and indoor, 10KV and below use the indoor type. Under a different scheme, can be classified as in-and-out switch cabinet, contact oil switch cabinets, counters, bussection. 10KV in-and-out oil-minimum breaker installed in the switch cabinet or vacuum breaker, breaker equipped with the actuator spring actuator or solenoid actuator, or permanent magnetic actuator with manual operating mechanism. Different switch cabinets differ in structure, which would affect the selection and installation of the sensor.



(B) fixed and remove



From the use of high-voltage switch cabinet, can be divided into fixed and removed.Yiqian, power plant auxiliary power system used to open switchg…

How to prevent short circuit between electrical circuits

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A, the causes of short circuit

(1) the connection error; (2) the insulation damage; (3) the operation error; (4) the mechanical damage

B, the harm of short circuit

Because of the short circuit current without load, only flows in the power source internal resistance is very small, so the current large, strong currents will generate heat effect and mechanical effect is large, the power supply circuit or damaged, or cause a fire.

C, the use of short circuit

Electric welding machine using the short circuit current on the electrode and the workpiece arc welding; motor starting current is large, can be connected in parallel to the switch current meter closes, meter short circuit, motor starting current is the current meter, the protective effect on the meter, after the

starting switch.

1, according to the specific circumstances of the appropriate selection of wire type. Usually must take into account the damp proof and heat proof, anti-corrosion, avoid insulation failure.

2, to regularly ch…

Electrical knowledge

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1, zero-sequence current protection of the protected area is how to divide?
I survived the end of the line of zero-sequence current earthing short circuit through the protection the maximum setting of zero sequence currents; do not protect thefull length of the line, but should not be less than the length of the protected circuit15%~20%; zero-sequence II general protection the total length of the line and extend to the adjacent lines within the scope of paragraph I, and cooperation. Zero-sequence III is I,II of reserve, and in conjunction with adjacent line.

2, computer protection different from the original relay?
Main difference is that the original protection of the input current and voltage signals, and direct comparison between the analog processing, analog and compare withthe devices in a given moment of resistance. And computers can only be numeric orlogical operations. Therefore, first of all require input of analog current, the instantaneous value of voltage transform of disc…

How to judge the fault causes from the abnormal vibration and sound of the asynchronous motor?

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Mechanical reasons:
① the motor fan is damaged or loose fastening screws of the blades, resulting in fan Ye Gai collide with the wind, its sound with the chink of light is small;
II bearing wear or shaft is not straight, causing motor rotor eccentricity, which the stator and rotor are clean, the motor produces excessive vibration and uneven grazing;

③ motor resulting from the long-term use of foot screw is loose or not steady, thusin the presence of the electromagnetic torque of the motor produces abnormal vibration;
About long-term use due to lack of lubricant in the bearing of the motor becoming a dry run or ball bearing damage, thus the motor bearing Chamber abnormal sibilance or purr.
Electromagnetic reasons:
①the exception occurred suddenly motor running sound, at run time with load, speeds decrease, and gave a low growl, may not be balanced three-phase current, overloaded or single-phase operation;
② motor in normal operation, if the stator and rotor winding fault or squirrel-ca…

What causes the no-load current of the asynchronous motor to be too big?

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Result in asynchronous motor no-load current reasons are the following:
① voltage too high: when the power supply voltage is too high, the motor produces magnetic saturation of the iron core, leading to excessive no-load current;
② motor due to improper Assembly or after repair the gap is too large;
③ number of stator winding is not enough or y-type connection error into the wiring;
④for some of the old motor, due to the silicon steel sheet to corrosion or aging, themagnetic field strength weakened or damaged insulation caused no load current is too large. For small motors idle current as long as you don't 50% you can continue to use the current rating.

What is the reason for the generator shaft voltage? What harm does it have on the operation of the generator?

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Causes of shaft voltage produced is as follows:

① because of generator stator flux imbalance in the shaft of the generator EMF is on. Reason of unbalanced magnetic field is usually because local magnetic stator core is large (such as corrosion of the stator iron core), as well as between the stator and rotor air gap not uniform.


② the bad shaft seal in turbine-generator, along the axis of a high-speed steam leakor high speed jet of steam in the cylinder so that the hinge itself for reasons of static charge. This kind of shaft voltage and sometimes very high, can make people feel.But at run time through the brushes ground, so there are actually has been eliminated. Shaft voltage is generally not high, usually no more than 2~3 v, in order to eliminate after bearing axis voltage, motor and formed the basis of the current loop, you can in the exciter side bearing pad insulation Board. The electrical disconnect, but when insulation pad due to oil, damaged or aging cause loss of role, shaft…

What is called anti jump blocking protection?

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The so-called "jump" means when the breaker is, because the control switch is not reset or control switch contact device, automatic contact stuck, resulting in
tripping control circuit is connected while still tripping, so the circuit breaker will repeatedly to "jump", we call this phenomenon as "jump". Jump protection is the use of the operating mechanism itself mechanical locking or another in the operating circuit to take other measures (such as the installation of anti jump relay, etc.) to prevent the phenomenon of jumping. The circuit breaker closing to fault line trip, not closed, even if the operating personnel will still control the switch is in the closing position, the circuit breaker does not occur "jump".

In three-phase four wire system, why not allow a part of the equipment to connect to zero, and another part of the equipment used to protect the ground?

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When the protective earthing of electrical equipment shell with a collision, the
earth resistance than the midline of the resistance is large, after the ends of the earth and the formation of shell lining, are not enough to make the short circuit power supply automatic switch and insurance action, and grounding power, and the power supply to the neutral point potential rise, make all zero line of electrical equipment shell or the frame of the voltage to the ground, will cause the electric shock more opportunities.

Relay protection in the abnormal fault, the duty personnel are allowed to what responsibility?

A, when the power station and the system and the occurrence of anomalies and accidents, such as the current impulse voltage drop system oscillation, over load, swing swing. Ground and switch automatic tripping, etc.) on duty to do the following work:

Check the signal drop down the situation;

Check sound, light signal issued;

Check the automatic tripping of the switch, the situation of the action of the automatic device;

The monitoring of current and voltage frequency and active power changes, the detailed records of the recorded signal, then according to the rules.

B, the results of the above inspection should be notified in a timely manner, the system scheduling and workshop leadership.

C, the following conditions shall be handled by the duty officer:

Replacement of light bulbs and insurance;

Selection of DC grounding.

Transformer over current protection action, on duty, how to deal with?

① to inspect if there is no obvious failure, transmission;

② Determining human malfunction, caused transformer protection switch tripped or contact the master scheduling system failures, causing the overcurrent protection and transformer oil switch tripping you can check immediately.

DC bus voltage is too high or too low to have any effect?

DC bus voltage is too high, the long-term running of the electrical components, such as the meter relay, light and so on are easily damaged due to overheating. And when the voltage is too low, it is easy to make the protection device malfunction or reject. General provisions of the allowable voltage change range is ±  10%.

What is the role of not returning off the card?

Drop signal not generally used to reflect the light plate and the alarm, which is characterized in that all the control loop, any signal is not restored, can emit light signal, to remind the personnel on duty or the operator according to the signal to find fault, not omission or false.

Central signaling device there are several? What is the use?

The central signal device has two kinds of accident signal and warning signal. The use of the accident signal is that when the circuit breaker is tripped, the circuit breaker can be used to send out the sound of the buzzer immediately, and the circuit breaker indicator lamp is flashing. The warning signal uses: in the abnormal operation of the equipment, can cause transient or delay bell sound, and the light plate showed abnormal phenomenon of content.

AC, DC circuit can apply a cable?

AC and DC circuit is not combined with a cable, the main reason is that the AC or DC loop are independent of the system, when a combination of AC and DC cables, AC and DC interfering each other, the insulation resistance of the DC current is reduced; at the same time, insulation system, and the exchange is connected the system between the two old friends, easy to cause a short circuit, DC cannot be combined with a cable.

What is the time limit? What is the counter time limit?

In order to achieve selectivity of over current protection should be the segments of the line protection operation principle of time steps to setting, that is from the power source nearer the end time is longer. Each differential of time is 0.5 seconds. Relay operation time and short-circuit current is independent of the size. Period of timedetermined by this time known as. Timed overcurrent relays electromagnetic limit,with a time relay for time characteristics, the model for the DL.
Inverse-time is the time and the short circuit current is independent of the size, when current is large, time is short, while long, take advantage of this feature made outof relays called inverse-time overcurrent relays. It is inductive, model for GL type. Itscurrent relationship with time can be divided into two parts: one for setting time limits, part of inverse time. When a short circuit when the current exceeds a certain ratio, current increases are no longer shorten the operating time, time characte…

How to choose the European table?

Selection of Megger, mainly is to select the voltage measuring range, high-voltageelectrical equipment required to use the high voltage megohmmeter. Low-voltage electrical equipment using low voltage ohmmeter. General principles are: electrical equipment selection of 500 kV 500~1000-Volt megohmmeter; vases, straps, switch should be used more than 2500 v Megger.
Megger measuring range selection principles are: to adapt the measuring range themeasured insulation resistance value produce large errors when reading. Some megohmmeter readings are not starting from scratch, but starting from 1 meg or 2 meg.This form is not suitable for determination of low-voltage electrical equipment in wet conditions the insulation resistance. Because the insulation resistance of such equipment may be less than 1 megohm, the instrument was not reading, easily mistaken for insulation resistance is zero, and draw the wrong conclusions.

S7-300 hardware configuration and module power consumption calculation method

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Using S7300 313C CPU plus IM365 extended a frame of.313C comes with its own 24DI16DO and 5AI/2AO analog input and output, see the manual configuration above CPU can be placed behind the 8 modules, would like to ask, CPU integrated I/O surface to exclude? No matter what CPU can be placed back 8 modules (on the right side of the CPU manual shall be installed more than eight modules (SM, FM, CP). The cumulative power consumption of the modules installed on the rack must not exceed 1.2 A on the S7-300 back board bus. The cumulative power consumption) do not know what is, refers to the frame all 5V power consumption? Do not know whether it can be understood that digital input can not find 5V power consumption, only the digital output and analog input and output can be found in the 5V power consumption value, using the IM365 extended time frame 1 only received signal accumulation; current load limit

For 1.2 A, in which the maximum current of rack 0.8 is 1 A, it can be understood that the ra…

DP network flash jump - how to diagnose system

These days with DP network jump problem: should be a few remote IO station off the station after a very short period of time to recover automatically, because these IO security module on the station, so will lead to part of the emergency shutdown, and from the perspective of diagnostic information (multi 16#3942 16#3842), the site is uncertain. And check these sites also found no obvious problems; for this problem, should cause how to find the problem? Can help give a more systematic approach?

Best answer

From the station site is not fixed, resulting in your bus communication is not stable, resulting in this situation generally have the following reasons:

1 do not have a strong anti-interference ability: usually the shielding layer DP line without good grounding, whether can use the multimeter to measure the DP line of the two and the resistance is close to 0, is too big a problem: piecewise measuring shielding layer is connected, and then into the cabinet in the DP line where the stripp…

6ES7 405-OKA01-0AA0 AS4 PS

405-OKA01-0AA0 AS4 PS 6ES7 and

405-OKA01-0AA0 AS400 PS 6ES7

Is there anything different in the two models?

Best answer

This is the 400 system of DC power supply module

The two order number you posted on the top is the same.

Is not posted on the wrong

And now the DC input 10A specifications of the power module to upgrade to 6ES74050KA020AA0 this order number

How to use a computer to achieve the same time on the two PLC access?

Recently the communication between two PLC, if you use SIEMENS's own words each cable programming procedure is very troublesome, for which a PLC after pulling down into another PLC again under the corresponding procedures, and online modify variable values and also not easy, so I would like to ask how to at the same time for two PLC were the program downloads and online monitoring? Seems to use the network cable, there is a corresponding operation guidance?
Best answer
1, how to simultaneously two PLC to carry on the procedure to carry on the procedure as well as the on-line monitor?
Not at the same time, it is respectively. The two sets of PLC are set IP address respectively connected.
2, through the network cable to download the program method:
Directly through TCP/IP or ISO mode can be specifically integrated PN can search your CP or CPU Edit-Edit Ethernet by Step7 node-Browse, online IP address allocation can be directly in the way of TCP/IP download.

300plc master and 200PLC as slave station group DP network related issues

A 300PLC CPU 314C-2DP the master station and three sets of 200plc CPU 226 DP network from a station group, communication module is EM277. Preliminary 300plc and 200plc Group DP network hardware is configured to download properly, but when more than two 200plc network, after downloaded into 300 (OB blocks without programming, hardware configuration only) SF light red when the switch is pushed to the RUN mode, the last light force switch to STOP mode. Ask the teacher what's theproblem?



The best answer


3 EM277 address is not the same, and with 300 addresses are not the same. EM277code consistent with the configuration of your address.
SF lights, can be viewed online access to the Diagnostics buffer problem.
In the procedure, add 0B82, OB86, OB121, OB122.

How to use S7-200 to write a time interval to run the motor program

For example, start, run 1H, stop 2H continues to run cycling 1H after such reciprocating motion


The best answer
Directly after this when the motor is running SM0.4 a minute pulse trigger an address added 1. When added to 60 motor stops, you can. Motor stops after running 2Hcan also be written like this

CPU224xp in the running state, switching back and forth in RUN and STOP What is going on

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CPU224xp to run, RUN and STOP switch back and forth, re-download and then well,don't know whether this is the case.


The best answer



You mean your PLC running times before failure, and when machine is it? If this is the case, even if you are normal, there will still be a problem in the future.
Because is now download has program Hou normal, is because you errors of premise conditions also not meet, for example a logo bit (this logo bit in you again download program Hou was clear zero has) closed Hou implementation has a cycle statement or addressing instruction, and this paragraph instruction is has problem of place (died cycle or find not to address), so once this premise conditions meet has, you of PLC also is being machine of.


SMART PLC S7-200 communication portal common knowledge to answer

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1th: communication is what?


Essentially communication ports around the combination of high and low level, to achieve 0 1 codes delivered between two devices, 0 is low level, 1 is high. Now, if I have a PLC and inverter communication, then the fact is hardware and cables throughthe communications port of the inverter produces combinations of high and low level and then delivered through the hardware code that translated into 01011010, thiscompletes the PLC to inverter data transmission. The same principle, frequency converter to the PLC return data the same way.


2nd: what is full duplex and half duplex?


Full duplex: communications port when sending data while also receiving data, the same time, send and receive simultaneously.
Half-duplex: communication ports at a time, or send or receive, plainly, is at the same time, had completed only one, either received or sent.


3rd: what is the baud rate?


Porter rate also said communications plastic rate, communications rate actually worth is 1s…