Siemens SINAMICS V20 Operating Instructions Manual page 345

Alarm Cause
A910 Occurs
Vdc_max
if main supply voltage (P0210) is permanently too high.
•
controller de-
if motor is driven by an active load, causing motor to go
•
activated
into regenerative mode.
at very high load inertias, when ramping down.
•
If warning A910 occurs while the converter is in standby
(output pulses disabled) and an ON command is subse-
quently given, the Vdc_max controller (A911) will not be
activated unless warning A910 is rectified.
A911 The Vdc_max controller works to keep the DC-link
voltage (r0026) below the level specified in r1242.
Vdc_max
controller
active
A912
The Vdc_min controller will be activated if the DC-link volt-
age (r0026) falls below the level specified in r1246.
Vdc_min
The kinetic energy of the motor is used to buffer the
controller
DC-link voltage, thus causing deceleration of the
active
converter! So short mains failures do not necessarily
lead to an undervoltage trip.
Note that this warning may also occur on fast ramp-ups.
A921 Analog output parameters (P0777 and P0779)
should not be set to identical values, since this would
Analog output
produce illogical results.
parameters
not set
properly
A922 No Load is applied to the converter.
No load ap- As a result, some functions may not work as under
plied to con- normal load conditions.
verter
A923 Both JOG right and JOG left (P1055/P1056) have
been requested. This freezes the RFG output fre-
Both JOG left
quency at its current value.
and JOG right
are requested
A930 Conditions exist for possible cavitation damage.
Cavitation
protection warn
A936 PID autotuning (P2350) selected or running
PID autotun-
ing active
A952 Load conditions on motor indicate belt failure or me-
chanical fault.
Load monitor-
ing warning
SINAMICS V20 Converter
Operating Instructions, 10/2019, A5E34559884-012
Remedy
Check the following:
Input voltage must lie within range.
•
Load must be match.
•
In certain cases apply braking resistor.
•
Check the following:
Supply voltage must lie within limits indicated
•
on rating plate.
Ramp-down time (P1121) must match inertia of
•
load.
Note:
Higher inertia requires longer ramp times; other-
wise, apply braking resistor.
Check the following:
Parameter settings for output identical
•
Parameter settings for input identical
•
Parameter settings for output do not correspond
•
to analog output type
Set P0777 and P0779 to different values.
Check that motor is connected to converter.
Do not press JOG right and left simultaneously.
See F410.
Warning disappears when PID autotuning has
finished.
See F452.
Faults and alarms
9.2 Alarms
343