4. Troubleshooting
4. Troubleshooting
4-1 Common Items
4-1-1 Stepping Out (Note 1)
The machine performs open loop servo control using a pulse motor (stepping motor) without positional feedback. The machine thus continues to operate with positional error even if it steps out due to overloading of the retaining torque of the motor.
When the base machine steps out, or when it operates with positional errors, check the following items first.
(1) Overloaded
The base machine has a limited carrying loading. Check whether the load exceeds the maximum payload that the respective axes can carry by referring to page
The payload with which the machine can operate at 100% speed is smaller than the maximum payload, and varies for each axis. Check the actual load weight before operating the machine.
(2) External force
External forces from cables and pipes are normally larger than anticipated, and can easily exceed the retaining torque of the motor. Be careful of unexpected external forces when using stiff wires or pipes that cannot be easily bent.
(3) Rapid speed change
When a rapid speed change occurs such as an immediate returning movement while an interpolation operation is being performed, the load inertia may exceed the retaining torque of the motor, causing the motor to step out.
Before performing such a movement, reduce the operating speed.
Example : Returning movement of the circular | Example : Returning movement of the |
interpolation operation | operation |
| (Movements are synthesized sometimes.) |
Note 1 : What is “stepping out”?
When the drive shaft of a motor is overloaded beyond the torque of the motor, the drive shaft spins (revolves swiftly without control) regardless of the control that is applied to the motor.
This is called “stepping out”.
This term is sometimes used incorrectly for