Siemens SINUMERIK 840D sl Series Diagnostics Manual page 694

Overview of Alarms
207422 <location>Drive: Reference model natural frequency > Shannon
frequency
Reaction: NONE (OFF1, OFF2, OFF3)
Acknowledge: IMMEDIATELY (POWER ON)
Cause: The natural filter frequency of the PT2 element for the reference model (p1433) is greater
than the Shannon frequency.
The Shannon frequency is calculated according to the following formula: 0.5 / p0115[1]
Remedy: - reduce the natural frequency of PT2 element for reference model (p1433).
- reduce the speed controller sampling time (p0115[1]).
207430 <location>Drive: Changeover to open-loop torque controlled operation
not possible
Reaction: OFF2 (NONE, OFF1, OFF3)
Acknowledge: IMMEDIATELY
Cause: For sensorless operation, the converter cannot change over to closed-loop torque-
controlled operation (BI: p1501).
Remedy: Do not attempt to cover over to closed-loop torque-controlled operation.
207431 <location>Drive: Changeover to sensorless operation not possible
Reaction: OFF2 (OFF1)
Acknowledge: IMMEDIATELY
Cause: For closed-loop torque control, the converter cannot change over to sensorless operation
(p1404).
Remedy: Do not attempt to change over to sensorless operation.
207432 <location>Drive: Synchronous motor without overvoltage protection
Reaction: OFF2 (OFF1)
Acknowledge: IMMEDIATELY
Cause: Under voltage conditions, a synchronous motor can generate an overvoltage condition that
can destroy the drive system.
Fault value (r0949, hexadecimal):
Associated drive data set (DDS).
Remedy: Overvoltage protection can be implemented in the following ways:
- limit the maximum speed (p1082) without any additional protection.
The maximum speed without protection is calculated from p1082 = 9590/p0316.
- use a voltage protection module (VPM) in conjunction with the function "safe standstill"
(p9601, p9801).
When a fault condition exists, the VPM short-circuits the motors. During the short-circuit,
the pulses must be cancelled - this means that the terminals for the safe standstill must be
connected to the VPM.
When using a VPM, p0643 must be set to 1.
See also: p0643
207433 <location>Drive: Closed-loop control with encoder is not possible as the
encoder has not been unparked
Reaction: NONE (OFF1, OFF2, OFF3)
Acknowledge: IMMEDIATELY
Cause: The changeover to closed-loop control with encoder is not possible as the encoder has not
been unparked.
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SINUMERIK 840D sl/840D/840Di/810D Diagnostics Guide (DA), 08/2005 Edition
© Siemens AG, 2005. All rights reserved
08/2005