Cycle of operation

This forum is not a homework outsourcing network. I suggest you engage your brain, learn to use a search engine as well as reading your course notes, and attempt to at least try and figure out some form of answer.

Then post it here along with the question again, and someone less grumpy than me may assist you.
 
False to true is not a cycle.

Think about the definition of a cycle as it applies to the operation of a machine. A washing machine may have several "cycles" such as "normal wash", "delicate", "water saver", etc.
 
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Try thinking of a cycle as a sequence of steps. At each step some different action takes place. Transition from one step to another occurs because of something that takes place during the step. The transition could be simply because of the passage of time or it could be due to a physical action. At the end of a cycle, the system is back in the same condition as it was when the cycle began.
 
HeavenKnows,

Say you had Steve's washing machine hooked up to a sequencer controller. This controller is programmed to go through a fixed routine for each and every cycle - add water, wash, spin & drain, add water, rinses, spin & drain.

Now suppose your girlfriend decides, "hey wait a minute, I need to have the machine stop every 2 minutes while I check on my delicate underwear from Victoria's Secret to make sure it is not being ripped to shreds."

How could those extra events be easily added to the sequencer's fixed cycle?

Answer: They can't.

So now answer the question, what type of a set of steps is best suited for a sequencer?
 
I think the question itself is improperly defined. Whats the context of the question?

It could mean also "what are the steps taken in plc cycle".
 
I think the question itself is improperly defined. Whats the context of the question?
Click to expand...
It is a student homework question. There is no context other than that defined in the problem. You know the drill, make your best answer based on the available information. My interpretation is that they are getting at the fact that sequencers work best where the sequence is completly defined and tested, fixed in place, and never changes. For a cycle that needs frequent changes, additions, or modifications, sequencer controllers will cause a lot of trouble.
 
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Lancie1 said:
It is a student homework question. There is no context other than that defined in the problem. You know the drill, make your best answer based on the available information. My interpretation is that they are getting at the fact that sequencers work best where the sequence is completly defined and tested, fixed in place, and never changes. For a cycle that need frequent changes, additions, or modifications, sequencer controllers will cause a lot of trouble.
Click to expand...

Excellent answer.....in the real world Sequencers sometimes cause as many headaches as they cure.

I usually end up writing my own ladder based state machine.
 
With context i did mean what is the area the questions are derived from. So basically, what did their teacher teach them.
 

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