8400 TopLine: FW version = 13.01.00.00
Response of the new version?
Noise of the differentiated setpoint speed (toggling of the 2 lowest-order bits) is masked out internally. Like this, toggling of the bLimTorqueSetAvl status by the natural setpoint noise is suppressed.
Which products are affected?
8400 HighLine and TopLine: 12.00.00.00 ≤ FW version ≤ 13.00.00.00
What happens? During homing to a mechanical limit stop, the 'Setpoint torque limitation' status does not permanently remain bLimTorqueSetVal=TRUE as expected. Even after several seconds, bHomePosAvailable does not become TRUE.
When does the problem occur?
If the following conditions are met at the same time, the response occurs:
· Homing to a torque limit C1221=14 or 15 is executed.
· A motor control type has been selected, which provides the function of the differential setpoint feedforward control for feedforward control of an acceleration torque: SC SM, SC ASM, SLPSM, and SLVC (C006=1-4).
· A moment of inertia considerably greater than 0kgcm² has been parameterised (sum of C273 and C919/1).
· The sensitivity of the setpoint feedforward control is set to a value higher than 14 bits (C653/1<2).
By the differentiation of a setpoint speed with natural noise (toggling of the 2 lowest-order bits), a short-time torque setpoint is applied, counteracting the actual setpoint from the homing process. For a short time this causes the bLimTorqueSetVal status to be reset to FALSE.
Diagnostics options?
For purposes of testing, set C653/1=2 sensitivity of the setpoint feedforward control 14 bits. Then the response does not occur anymore.
Short-term measures/recommendations?
Set C653/1>1.
Evaluation:
Homing to a mechanical limit stop does not work anymore after a device replacement with FW upgrade. A connection to the acceleration feedforward control is not apparent. After the cause has been identified, the function can be restored by a parameter adaptation.
