Page 729 - Mechatronics with Experiments
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PROGRAMMABLE LOGIC CONTROLLERS 715
five in a row, 1.0 in displacement motions separated by 100 ms delay between the completion and
start of each motion. Specify the necessary PLC hardware and design the program logic.
4. Consider the circuit shown in Figure 9.9. What happens if the seal-in circuit at points 3 and 4 was
not connected? If the seal-in circuit is not connected, and we change the “Start” switch to a latching
switch (not momentary), how is the operation of the circuit different than the seal-in circuit operation
(consider that if we started the circuit and stopped it with the “Stop” switch, how would you re-start
the system)?
