Problems and obstacles is the Back Signal.
In which parts of the signal, this Signal Back to the problems that most Limit Switch due to a leg of a switch with a long lifetime, because the device has a lifetime count as the number of times which makes it work, and in some cases it's frictionless, loosen the leg until the switch legs touching not arrive so no signal Signal Back to the user in order to control the production process. I need to slow down the Feed in the step must wait to check the actual work of the valve, which allows more time for in-process, but in this section simply does not have much impact on production processes.