Siemens Energy & Automation  9-17 
SIMOREG DC Master Base Drive Panel   Operating Instructions 
Fault  Description 
No. 
Cause as a function of fault value 
(r047.001, r949.001 or r949.009 with acknowledged error) 
Further information (r047.002 to r047.016) 
 
20  Current limit is too low 
(With speed controller optimization run: Less than 30% or 45% of P100 (I
A,motor
) + the armature current required for zero 
speed, 
With optimization run for friction moment and moment of inertia compensation: Less than 20% of P100 (I
A, motor
) + the 
armature current required for a steady-state speed corresponding to 10% of maximum speed) 
 
21  Field weakening range is too wide (n
act
 < +7% n
max
 
 produces |EMF| > 54% setpoint EMF) 
  (setpoint EMF= K289= P101 – P100 
*
 P110) 
Possible cause: 
•  Maximum speed setting is incorrect 
•  Pulse encoder parameters are incorrect (P140 to P143) 
•  Parameters for tachometer adaptation are incorrect (P741) 
•  Setpoint EMF is not correct (P101, P100, P110) 
• Caution: 
Even a high absolute negative actual speed value can produce an | EMF | of > 54% setpoint EMF 
 
22  With speed controller optimization run: 
With an acceleration current equaling 20% or 30% of P100 (I
A, motor
) + armature current required for zero speed or 
  With optimization run for friction moment and moment of inertia compensation: 
With an acceleration current equaling the current required to achieve a steady-state speed of 10% of maximum speed + 
20% of P100 (I
A, motor
), the maximum speed cannot be reached within 45s +7% 
Possible cause: 
•  Centrifugal mass is too large 
•  Drive is blocked, heavily speed-dependent or excessively high load torque 
•  “Active” load is attempting to maintain a certain speed 
Possible remedy: 
•  Increase P100 while the optimization run is in progress in order to raise the applied acceleration current during 
optimization (during the speed controller optimization run, a maximum of 45% of I
A, motor
 
(+ armature current for zero 
speed) is applied as the armature current setpoint, I
A,motor
 (P100) can thus be increased to 2.2 times the value at 
maximum without exceeding 100% I
A, motor
 during optimization) 
 
23  With speed controller optimization run: 
With an acceleration current equaling 20% or 30% of P100 (I
A, motor
) + armature current required for zero speed or 
  With optimization run for friction moment and moment of inertia compensation: 
With an acceleration current equalling the current required to achieve a steady-state speed of 10% of maximum speed + 
20% of P100 (I
A, motor
), the maximum speed or 100% of setpoint EMF cannot be reached within 90s +13%  
Possible cause: 
•  Flywheel mass is too large 
•  Drive is blocked, heavily speed-dependent or excessively high load torque 
•  “Active” load is attempting to maintain a certain speed 
Possible remedy: 
•  Increase P100 while the optimization run is in progress in order to raise the applied acceleration current during 
optimization (during the speed controller optimization run, a maximum of 45% of I
A, motor
 
(+ armature current for zero 
speed) is applied as the armature current setpoint, I
A,motor
 (P100) can thus be increased to 2.2 times the value at 
maximum without exceeding 100% I
A, motor
 during optimization) 
 
24  With speed controller optimization run: 
The actual speed does not drop to below +2% of maximum speed or to below the speed threshold n
min
 
set in P370 within 2 
minutes 
  With optimization run for field weakening: 
The actual speed does not drop to below +2% of maximum speed or to below the speed threshold n
min
 
set in P370 within 
10 minutes 
  With optimization run for friction moment and moment of inertia compensation: 
The actual speed does not drop to below +2% of maximum speed or to below the speed threshold n
min
 
set in P370 within 
11 or 2 minutes 
Possible cause: 
•  Single-quadrant drive coasts to a standstill too slowly