8.5 Estimating the Moment of Inertia
8.5.2 Restrictions
8-16
8.5.2
Restrictions
The following restrictions apply to estimating the moment of inertia.
Systems for which Execution Cannot Be Performed
•
When the machine system can move only in one direction
•
When the range of motion is 0.5 rotations or less
Systems for Which Adjustments Cannot Be Made
Accurately
•
When a suitable range of motion is not possible
•
When the moment of inertia changes within the set operating range
•
When the machine has high dynamic friction
•
When the rigidity of the machine is low and vibration occurs when positioning is performed
•
When the position integration function is used
•
When mode switching is used
Note:If you specify moment of inertia estimation, mode switching will be disabled and PI control will be used
while the moment of inertia is being calculated. Mode switching will be enabled after moment of inertia esti-
mation has been completed.
Preparations
Always check the following before you execute moment of inertia estimation.
•
The main circuit power supply must be ON.
•
There must be no overtravel.
•
The servo must be OFF.
•
The gain switching selection must be set to disable automatic gain switching (Pn139 =
n.
0).
•
The first gains must be selected.
•
The test without a motor function must be disabled (Pn00C = n.
0).
•
There must be no alarms or warnings.
•
There must be no hard wire base block (HWBB).
•
The parameters must not be write prohibited.
•
The tuning-less function must be disabled (Pn170 = n.
0).
8.5.3
Applicable Tools
The following table lists the tools that you can use to estimate the moment of inertia and the
applicable tool functions.
Tool
Function
Operating Procedure Reference
Digital Operator
You cannot estimate the moment of inertia from the Digital Operator.
S
Tuning - Tuning
