da2g
Member
I am a very inexperienced, self taught, plc programmer. I have taken Phil’s course, and have programmed a handful of Automation Direct DL05 plc’s to automate some of our factory processes. My programming to date has been very simple (two state switches/sensors for inputs, relay outputs to control solenoid operated valves). Beyond this, I will need help and further study.
For my latest project, I would like to automate an assembly and test station. This will require drawing a vacuum in a test piece, sampling the vacuum inititially, then again at a later time (say 5 seconds), comparing the difference and determining whether this value exceeds a maximum allowable limit. Based on the result, the part would either be rejected, or subject to additional processing.
I will also need a time delay between actuation of a valve that connects the test piece to a vacuum source, and the first vacuum sample, to allow the cavity to be evacuated fully, and to close the vacuum source valve.
I anticipate that I will use a 4-20 mA vacuum sensor (4 mA at atmospheric pressure, 20 mA at –14.7 psi. We can tolerate a maximum loss of .24 psi of vacuum in 5 seconds (0.048 psi/second).
My experience with DirectSoft Box instructions is minimal. I would appreciate any direction to get me started, such as how to implement the time delay for the first and second samples, how to write to memory for the two different samples from the sensor, and what memory locations to use.
Many thanks in advance.
For my latest project, I would like to automate an assembly and test station. This will require drawing a vacuum in a test piece, sampling the vacuum inititially, then again at a later time (say 5 seconds), comparing the difference and determining whether this value exceeds a maximum allowable limit. Based on the result, the part would either be rejected, or subject to additional processing.
I will also need a time delay between actuation of a valve that connects the test piece to a vacuum source, and the first vacuum sample, to allow the cavity to be evacuated fully, and to close the vacuum source valve.
I anticipate that I will use a 4-20 mA vacuum sensor (4 mA at atmospheric pressure, 20 mA at –14.7 psi. We can tolerate a maximum loss of .24 psi of vacuum in 5 seconds (0.048 psi/second).
My experience with DirectSoft Box instructions is minimal. I would appreciate any direction to get me started, such as how to implement the time delay for the first and second samples, how to write to memory for the two different samples from the sensor, and what memory locations to use.
Many thanks in advance.