
B–63523EN–1/03
2. PREPARATIONS FOR OPERATION
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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 the load torque on the
motors and sends this value as an estimated load torque to the PMC. If
the detected load torque value 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 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, whenever 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.)
Abnormal load detection can also be disabled only for specific axes by
using bit 5 (ABDSW) of parameter No. 2215 for the abnormal load
detection function and abnormal load detection ignore signals IUDD1 to
IUDD8 <G0125>. (This function is effective only for servo motors.)
2.10
ABNORMAL LOAD
DETECTION
General