
B–63503EN–1/01
2. PREPARATIONS FOR OPERATION
101
Machine collision, defective, and damaged cutters cause a large load
torque on the servo and spindle motors, compared with normal rapid
traverse or cutting feed. This function detects a load torque on the motors
and sends it as an estimated load torque to the PMC via the CNC. If the
detected load is abnormally great compared with the value specified in the
parameter, the function stops the servo motor as early as possible or
reverses the motor by an appropriate value specified in a parameter, in
order to minimize a possible damage to the machine. (The function to
reverse motors is effective only for servo motors.)
The abnormal load detection function is further divided as follows:
(1)Estimated load torque output function
The CNC is always calculating the estimated load torque for the motor
(excluding acceleration/deceleration torque). The estimated load
torque output function enables the PMC to read the calculated torque
using the window function.
(2)Abnormal load detection alarm function
This function stops motors or reverses them by an amount specified
in a parameter, causing the CNC to output an alarm, if the load torque
obtained by the estimated load torque output function is greater than
the value specified in a parameter. (The function to reverse motors is
effective only for servo motors.)
2.9
ABNORMAL LOAD
DETECTION
General