I need to write a PLC program for a Click PLC by Automation Direct. This PLC will control a box filler that has various inputs and outputs. Let's go over the I/O
Inputs:
Photo Eye 1 (PE1) : Box in Filler
Photo Eye 2 (PE2): Box obstruction
Limit Switch 1 (LS1): Cycle Complete
Weight of Box (Wt): RS232 scale
Outputs:
Cycle Motor Contactor 120v (C1)
Gate Solenoid 120v (GS1)
Filler Belt Forward (FB1)
Filler Belt Speed to DC Drive 4-20mA (FBS)
Operation:
Empty Box in Filling Position. Confirmed by PE1
PE1 closed = box in filling position
PE2 open = box NOT in filling position
If PE1 is open... GS1 always open
-This means the gate solenoid does not engage and product cannot begin filling the box
If PE1 is open... FB1 always open
-This means the belt cannot begin flowing product to the box
If PE1 is closed... GS1 closes to engage solenoid to open the gate
Time Delay 1 (TD1) - After GS1 closes TD1 begins. FB1 follows TD1.
FB1 closes to start the belt.
As product begins to fill the box, the weight of the box increases. Indicated through the RS232 connection to the scale. A 3 speed line is desired to control the speed of the belt (FBS)
FBS =
Constant Speed 1 when Wt < X1
Constant Speed 2 when X2 > Wt >= X1
Constant Speed 3 when Wt >= X2
When Wt = X3
GS1 opens (closing the filling gate)
FB1 opens (stopping the filler belt)
PE2 checks for box obstruction
If PE2 is open (no box obstruction)
C1 closes to engage box cycle
C1 remains closed until LS1 closes + Time Delay 2 (TD2)
When LS1 closes TD2 begins
C1 opens after TD2 (stopping the cycle)
TD2 is a very short time delay to ensure the cam that closes LS1 moves to the open position. This can also be configured to open C1 when LS1 moves from open to closed to open. However for now, we will keep TD2 in play.
After C1 opens, a new box is in the filling position. PE1 confirms new box is in position and the process repeats.
Deliverables:
Click PLC model recommendation and additional expansion cards if needed.
-Ethernet and RS232 required
-I will follow up with the voltages for the various sensors particularly the photo eyes and solenoids.
DC Drive recommendation. 4-20mA speed signal. HP 90V motor
-The speed control is not set in stone. But a 4-20mA signal works for me
PLC wiring diagram
-I/O of PLC to the component
PLC ladder logic program
-No passwords
PLC program with appropriate variables
-No hard variables. Connecting HMI to change these dynamically
Research the scale and write the code to extract a live weight reading from the scale listed.
-Figure out how this scale can output a real-time weight. Also research a 'tare' function and if that is possible.
CMORE Touch HMI will be connected to change variables in PLC. I will be connecting this device.
Variables needed to change in HMI:
TD1 - Time Delay between gate open and belt start
X1 - Weight for speed change from speed 1 to speed 2
X2 - Weight for speed change from speed 2 to speed 3
X3 - Weight for "full box"
Speed 1
Speed 2
Speed 3
TD2 - Time Delay for cam to pass over LS1
I can also send pictures of the machine after acceptance.
Thanks for checking in on this project!
About the recuiterMember since Mar 14, 2020 Kannan Vengaiya
from Baden-Württemberg Region, Germany