exd3686,
Was finally able to draw something up for you. Keeping it simple is a lot harder than you may think.
The attached is in the form of a ladder diagram which shows current flow and not how the wires are physically laid out. In this ladder diagram everything is shown in a de-energized state and with no limit switches tripped.
With this particular circuit all you need is one On/Off switch, two limit switches and two relays.
The operation is as follows...
With target plate in the raised position, Up LS on the first rung goes from a normally closed position to a held open position preventing relay Up R from energizing. The normally closed contact on the first rung for Dn R is an electrical safety interlock, a safety feature which prevents both relays from energizing at the same time.
Once the target has been hit and begins to fall Up LS changes state from held open to normally closed energizing Up R and the actuator begins to raise even before the plate has completed it's fall (take this into concideration in your mechanical layout). The actuator continues to extend raising the target plate back to it's upright position tripping Up LS once again.
On rung two with the target plate in the raised position the normall open contacts in Up LS are now held closed and allows current to flow through normall Closed Dn LS contacts to coil Dn R through normally closed contacts in Dn LS engizing coil Dn R closing normally open Dn R contacts on rung two line two. Current continous to flow through electrical safety interlock normally closed contacts for Up R.
When the actuator arm is retracted to it's "home" position Dn LS is tripped and Dn LS normally closed contacts on rung two open and stop current flow to relay Dn R. With Dn R de-energized Dn R contacts on rung two line two revert to normally open.
Once the actuator arm is in "home" position the circuit waits for the target plate to fall again and the whole process begins again.
Rungs three and four depict how the motor is connected for forward and reverse operation.
Things to make note of...
The Up LS is tripped by the raised target plate.
The Dn LS is tripped by the actuator arm in the home position.
The internal actuator limit switches were not utilized but kept as an added safety feature. If for any reason any of the limit swithes or relays fail the internal limit switches will stop the actuator motor before burn out.
Hope this make some sense to you,
williamj
Was finally able to draw something up for you. Keeping it simple is a lot harder than you may think.
The attached is in the form of a ladder diagram which shows current flow and not how the wires are physically laid out. In this ladder diagram everything is shown in a de-energized state and with no limit switches tripped.
With this particular circuit all you need is one On/Off switch, two limit switches and two relays.
The operation is as follows...
With target plate in the raised position, Up LS on the first rung goes from a normally closed position to a held open position preventing relay Up R from energizing. The normally closed contact on the first rung for Dn R is an electrical safety interlock, a safety feature which prevents both relays from energizing at the same time.
Once the target has been hit and begins to fall Up LS changes state from held open to normally closed energizing Up R and the actuator begins to raise even before the plate has completed it's fall (take this into concideration in your mechanical layout). The actuator continues to extend raising the target plate back to it's upright position tripping Up LS once again.
On rung two with the target plate in the raised position the normall open contacts in Up LS are now held closed and allows current to flow through normall Closed Dn LS contacts to coil Dn R through normally closed contacts in Dn LS engizing coil Dn R closing normally open Dn R contacts on rung two line two. Current continous to flow through electrical safety interlock normally closed contacts for Up R.
When the actuator arm is retracted to it's "home" position Dn LS is tripped and Dn LS normally closed contacts on rung two open and stop current flow to relay Dn R. With Dn R de-energized Dn R contacts on rung two line two revert to normally open.
Once the actuator arm is in "home" position the circuit waits for the target plate to fall again and the whole process begins again.
Rungs three and four depict how the motor is connected for forward and reverse operation.
Things to make note of...
The Up LS is tripped by the raised target plate.
The Dn LS is tripped by the actuator arm in the home position.
The internal actuator limit switches were not utilized but kept as an added safety feature. If for any reason any of the limit swithes or relays fail the internal limit switches will stop the actuator motor before burn out.
Hope this make some sense to you,
williamj
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