The sequence control method that imitate measures -- PLC process designing is algorithmic

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Introduction: Purpose of switch quantity pilot is, the inputs combination and history currently input that measures according to switch is ordinal, make PLC produces corresponding switch to measure output, in order to make the system can press regular ordinal job. So, also call its sequence control sometimes. One, summarize 1, switch quantity also weighs logistic quantity, point to only two take a cost, 0 or 1, ON or OFF. It is the most commonly used control, undertake to it control is the advantage of PLC, also be the application with the most fundamental PLC. Purpose of switch quantity pilot is, the inputs combination and history currently input that measures according to switch is ordinal, make PLC produces corresponding switch to measure output, in order to make the system can press regular ordinal job. So, also call its sequence control sometimes. And sequence control is divided again move for the hand, semi-automatic or automatic. And adoption control principle has dispersive, concentration and mixed control 3 kinds. 2, imitate quantity is the physical quantity that points to a few successive change, wait like voltage, electric current, pressure, speed, discharge. After by afterwards report control brings in a subtle way to handle a technology, develop and PLC comes, can go to the lavatory reach reliable ground to be used at switch to measure control. Because imitate quantity can be changed into digital amount, digital amount is many switch quantity only, the imitate after reason classics is changed is measured, PLC can undertake reliably completely also handling controlling. Because successive manufacturing process often has imitate to measure, so imitate measures control to also call a process control sometimes. Imitate measures much dispute n, and PLC can handle digital amount, n only. All wanting that realize the changeover between them to want to have sensor, change imitate volume into several n. If this one n is not of the standard, send through changing even implement, turn nonstandard n into telegraphic name of the standard, be like 4, 20mA, 1, 5V, 0, 10V is waited a moment. At the same time even imitate measures input unit (A/D) , alternate the electric signal of these standards into imitate of digital signal; the quantity exports unit (D/A) , measure with changing the digital quantitative change after PLC is handled into imitate -- telegraphic date of the standard. So the changeover between amount of standard report signal, number is about to use all sorts of operation. The telegraphic date that this makes clear to Hunan imitate measures unit resolution and level with respect to need. For example: The resolution of PLC simulation unit is 1/32767, corresponding standard n is 0, 10V, what place should detect is temperature value 0, 100 ℃ . So 0, 32767 correspondence 0, the temperature value of 100 ℃ . Calculate next the digital amount that gives correspondence of 1 ℃ place is 327.

67. If think of a temperature value is exact 0.

1 ℃ , 327.

67/10 can. Imitate measures control to include: Feedback control, before control of make a present of, scale control, ambiguous control. These are the computational processes that PLC in-house number measures. 3, impulse of arteries and veins is its take a value to always be in ceaselessly 0(low n) with 1(tall n) between the digital amount of alternant change. The frequency that per sec. pulse changes alternately calls frequency. The control purpose of impulse of PLC arteries and veins basically is positional control, sport control, orbit control. For example: Pulse number controls medium application in angle. The fractionize that the pace takes electric machinery drive is every are encircled 10000, demand situation rotates into electric machinery 90 degrees. So the =10000/(360/90)=2500 of pulse numerical value that wants an action. 2, the computation that imitate measures 1, - 10, 10V. - 10V, when the voltage of 10V, be changed to be F448 when 6000 resolution, 0BB8he(-3000, be changed to be E890 when 3000);12000 resolution, 1770he(-6000, 6000) . 2, 0, 10V. 0, when the voltage of 10V, be by changeover when 12000 resolution 0, 1770he(0, be by changeover when 6000);12000 resolution 0, 2EE0he(0, 12000) . 3, 0, 20mA. 0, when the electric current of 20mA, be by changeover when 6000 resolution 0, 1770he(0, be by changeover when 6000);12000 resolution 0, 2EE0he(0, 12000) . 4, 4, 20mA. 4, when the electric current of 20mA, be by changeover when 6000 resolution 0, 1770he(0, be by changeover when 6000);12000 resolution 0, 2EE0he(0, 12000) . Above makes simple introduction only, different PLC has different resolution, the span that and you measure physical quantity comes true is different. Computation may have certain difference as a result. Note: The requirement of the layout that imitate inputs: 1, use screen double skeining thread, but do not join screen layer. 2, input unused moment when, v IN and COM terminal weak point is received. 3, imitate line and power supply cord are kept apart (AC power supply cord, the) such as the high tension line. 4, when there should is interference on power supply cord, wave of a Lv is installed between input part and power source unit implement. 5, after affirming correct wiring, give CPU unit electrify above all, give laden electrify again next. 6, the power source that load cuts off first when cutting off the power, cut off the power source of CPU again next. 3, the control of the impulse of computational arteries and veins of impulse of arteries and veins is multi-purpose the angle control that takes electric machinery, servo electric machinery at the pace, space control, position control. It is below it is into electric machinery with the pace exemple will explain each control fashion. 1, the pace is controlled into the angle of electric machinery. Want to make clear a pace to advance the fine mark of electric machinery above all, decide the situation turns into electric machinery next the total pulse number that circuit place needs. Computation " angle of set of = of angle per cent / 360 ° (namely circuit) " " per cent of angle of * of number of total pulse of circuit of = of number of angle movement pulse. " formula is: Angle of set of *(of number of total pulse of circuit of = of number of angle movement pulse / 360 ° ) . 2, the pace is controlled into the distance of electric machinery. Make clear a pace to turn into electric machinery above all the total pulse number that circuit place needs. Decide the pace enters diameter of electric machinery gyro wheel next, circumference of computational gyro wheel. Computation each pulse runs a distance. What distance of final computation set wants the pulse number that run. Formula is: Set of = of number of set distance pulse is apart from / [(*3 of gyro wheel diameter.

14)/ circuit total pulse is counted] 3, the pace is controlled into the position of electric machinery even if angle control and distance pilot are integrated. Above is the control kind that simple analytic pace takes electric machinery only, likelihood and have discrepancy actually, offer each colleague reference only. 4, what the movement of servo electric machinery and pace enter electric machinery is same, but the decelerate of gear comparing and servo electric machinery compares the in-house electron that should consider servo electric machinery. CNC Milling CNC Machining