220v-900w电热管 220v-900w加热管 220v-900w加热器
220v-900w电热管diagram should be at least one step early, and early step in parallel parking dash is reset Settings. Step is from top to bottom or from left to right operation process, will they have to connect with straight line. Steps such as S20 back to S21 dash said in the middle of the transfer conditions (here is based on a timer transfer conditions), the only condition is met, step to shift from the previous step to the next step, step and transverse connection, such as S20 corresponding Y0, T0 the meaning expressed by the step when the system is in the S20, called the step step activity, corresponding Y0, T0 action taken. Similarly run in S21 steps which then becomes active when (while S20 in inactive state, the corresponding step by stop execution), and the corresponding Y1, T1 is executed. The transition conditions is T1, step conditions once met will shift to S20, into the circulation. Step according to the need can also turn to S0 completed single work process and in the standby state. Figure 5 ladder diagram is derived according to the sequence function diagram. Require students to master the function diagram drawing and conversion between them.
Four, stepping sequence control programming methods and steps220v-900w电热管
Step 1, the PLC automatic control programming, programming methods have a single sequence, selection sequence and the programming method of parallel sequence, as to choose the kind of programming method is determined by process control requirements. But no matter adopt what kind of programming method, the method 220v-900w电热管