The process designing measure of PLC

Scientific process designing measure actually very simple, but often most engineer thinks simple and oversight is very much namely detail. The oversight of detail, the problem appears after inevitable meeting is in. Want to avoid in the future problem, only well toe the mark, do not become circumference without custom, PLC process designing has the rule of its oneself euqally. Next mask body introduce the reasonable measure of PLC process designing: The first pace: Read product manual. The first pace did not pass again simply it seems that, engineer of a lot of equipment can say, I was in charge of this equipment a lot of years, care and maintenance is done everyday, without unfamiliar, seeing a manual is wasteful time. Ha, this is the common fault of a lot of engineers of domestic, a lot of people are bought from equipment until discard as useless, truly serious without the person ground goes reading product manual, although read,also be carelessly ground looks. More returning is through offerring money square product grooms will know equipment, what does not know, if groom simply,can make you sufficient understand the word of equipment characteristic, so why to ask equipment wants to deploy a manual on international? If had read a manual, excuse me manual most initial safe regulations whether one word had looked? Whether has the specification of every component looked? Do not have kind of component whether to debug a method to had looked? ... we can discover, we are actually daily oversight product manual, a lot of people throw away the manual even or put in the place that oneself are unable to call to mind temporarily. Read the first situation that the manual is process designing carefully, want to read safe regulations above all, know what actuator may cause harm to person, what interagency is the most incidental bump, how to solve when producing risk, these the vitallest issues are in safe regulations, why to look? In addition, about equipment the character of every component, use method, debug a method to also be in the manual, do not go reading, although the procedure is correct, if component was not debugged good, equipment cannot work euqally. Have again, figure of all circuit graphs, return of pneumatic hydraulic pressure, assembly drawing also is in the manual, do not go reading it how to know to do not have kind of component to be able to be done why to plant transform. The 2nd pace: According to the manual, check I/O. Affirm manual of careful read through? If had been read carefully really, so have the 2nd situation, check I/O, common says " get ready " . The method that checks I/O is very much, but the address that must supply according to the manual is ordinal undertake checking. Premise is the specification of the safe regulations according to the manual and component, come down to check in the circumstance of absolute safety. When the examination inputs a dot, no more than of general input signal is all sorts of sensor, like capacitance, inductance, photoelectricity, press switch of type of feeling of block, ultrasonic, magnetism and journey to wait for sensor. Examine these cell simpler, according to component the specification puts work in labour on, or it is mobile actuator checks sensor to whether have signal can. Of course, the kind that different equipment detects may be different, this should treat specific condition and decided. But be about to take care all the more when the examination outputs signal. If be electric drive product, must fall in safe circumstance, make sure equipment won't happen especially bump premise, the driver that lets actuator gets report, whether can examination actuator move. If be hydraulic pressure or pneumatic actuator, start to move in safe circumstance likewise make reversal valve gets report, control actuator thereby. When the examination outputs signal, no matter what is the drive means of actuator, must according to component manual, want to assure equipment and person safety above all, the actuator that wanting an attention is not all equipment is OK electrify checks, output signal individually sometimes so likelihood cannot the hand uses a test. No matter be input or take-off, after sensor has signal or the actuating device of actuator gets report, whether does the I/O module indicator light that must check PLC to go up at the same time also illume. In a lot of equipment, inputting output signal is to pass wiring terminal and PLC join, sometimes the indicator light of wiring terminal has signal, but unwarrantable because join lead interior opens circuit, and the corresponding address on PLC puts through without signal. This want special attention. After measuring an input to output signal, the address record that wants to will be measured at the same time comes down, assure to agree in signal address and manual. If have,differ, measure equipment address again, measure for many times abhorrent still, contact equipment manufacturer first, do not have a mistake because of the address that right now unwarrantable manufacturer supplies. The 3rd pace: Open process designing software, undertake hardware is configured, keep I/O address in symbolic watch. Different PLC uses different process designing software. But to a kind of any software, the first pace before process designing undertakes hardware configuration namely, build hardware configuration and corresponding communication configuration according to the type of actual PLC. After hardware configuration is finished, will before in the symbolic watch that the I/O address that comes down in the record on paper keeps in software. Because software is different, the definition that expresses to the symbol may be different, but general software has this function, this one pace is crucial. When writing a symbol to express, want a facility not only input-output absolutely address is written correct, had better name to every address again and add explanatory note, this will be very convenient to the process designing from the back. Do not need to inquire absolutely address every time when process designing, should fill in only the name that has named can. Of course, this also depends on whether does software have this function. The 4th pace: Draw up program flow chart is before process designing, must draw up on rough draft the flow chart of the program. A whole process, should include a main program, stop to stop the share such as program, restoration program program, urgently, if software allows, should press each programs " piece " the form is written, namely a program is piece, final will every piece will call by demand can. PLC most those who be good at is processing sequence control, in sequence control mainstream Cheng is core, must ensure the circuit that has made is correct, should go up in rough draft microscope. If mainstream Cheng is put in the problem, after the program is carried out by PLC, happen probably bump, attaint equipment or create risk to person. The expression of flow chart the method is varied, here does not do specific specification. The 5th pace: After if ensure mainstream Cheng does not have a problem,the program is written in software, can write a program in software. In addition, notice to stop even, stop the validity with restoration program urgently, stop especially and stay a course urgently, this is the most important program that matters to person safety and equipment safety, absolutely cannot small inspect. No matter,must assure for love or money, should carry out only stop or stay a course urgently, equipment won't cause harm to person absolutely. Have again, any equipment have his initiative place, common device provided the safe initiative place of equipment in the manual. If do not have, should study its are initiative carefully the position, assure the rationality of initiative position. The 6th pace: Debug a program debugging a program in this one pace, can divide into two respects. 1.

If the condition allows, or the logistic ability that is you exceeds strong, the emulation function that can use software first does a test, but a lot of trival programs are emulated very hard with software see whether the procedure is correct. 2.

Will pass in PLC to undertake on-line is debugged below the program. If equipment is not moved or unusual situation appears in moving, do not modify a program first, probable it is sensor was not debugged reach the designated position, if ensure sensor is not had by accident, go modifying a program again. The 7th pace: Debug after finishing, again editor is in of on one pace in debugging, because be revised somewhat to the program, reason must rectify check-up to check again or edit a program, in PLC is being passed below will final order next. The 8th pace: Save a program to be in this one pace, want to note a problem, should defend the program existence where namely? PC hard disk? Shine keep equipment? Mobile hard disk? Of course these are not OK, all these storage equipment contract virus possibly. So, must and can get on program fire to CD only. And still have a problem, which program is the program of fire? Be in before in we will been debugged finally and revising finished program to download PLC, if PLC is in,do not have completely by accident if, in uploading this program PC, go to this program fire in CD. After the process designing that finish, should fill in to debug a report finally, record the problem of a few difficulty of the problem that encounter and program one by one come down. Because long later, oneself also can be forgotten to the place of the certain skill of the program, at the same time convenient also and other staff can understand the program that you write. CNC Milling