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As a quick exercise, make a rule for the "Settle" state that if the time exceeds 300 30 seconds then switch back to the "Add Chemical" state.
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We're not done yet! Your next task is to add another state "Drain" to drain the experiment. Set the time for the drain state not to exceed 10 100 s. You should then set the order of processes to be "Add Chemical" state switching to the "Settle" state switching to the "Drain" state. The "Drain" state should then switch back to "Add Chemical" state. In this sense, we are creating a cyclical process that could run indefinitely. In the "Drain" state set the "Drain Valve" to ON.
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