
2.PREPARATIONS FOR OPERATION B-63943EN-1/02
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2.9 UNEXPECTED DISTURBANCE TORQUE DETECTION
FUNCTION
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 disturbance torque
on the motors and sends this value as an estimated load torque to the
PMC. If the detected disturbance 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 unexpected disturbance torque detection function is further
divided as follows:
(1) Estimated disturbance torque output function
The CNC is always calculating the estimated disturbance torque
for the motor (excluding acceleration/deceleration torque). The
estimated disturbance torque output function enables the PMC to
read the calculated torque using the window function.
(2) Unexpected disturbance torque 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 disturbance torque is greater than the value
specified in a parameter. (The function to reverse motors is
effective only for servo motors.)
(3) Unexpected disturbance torque detection group function
This function allows you to divide servo axes into desired groups.
When the disturbance torque obtained by the estimated
disturbance torque output function is greater than a parameter-set
value, this function stops motors immediately. The function
immediately stops all axes that are set for the same group by
parameter setting (including axes of which group number set to
0) then places them in the interlock state. When a value is set in
parameter No. 2103, this function reverses the motors by the set
amount in a direction opposite to the advance direction, then
places all the axes of the same group in the interlock state.
NOTE
Select the unexpected disturbance torque
detection alarm function or unexpected
disturbance torque detection group function by
setting bit 5 (ANA) of parameter No. 1804.
You cannot use these functions at the same
time.
Unexpected disturbance torque detection can also be disabled only for
specific axes by using bit 5 (ABDSW) of parameter No. 2215 for the
unexpected disturbance torque detection function and unexpected