Technical data and characteristics 
  6.1 Explanations of the formula abbreviations 
1FW6 Built-in torque motors 
Configuration Manual, 07/2017, 6SN1197-0AE00-0BP9 
161 
Torque-speed diagram with field weakening  
 
S1 duty with field weakening 
S3 duty, cycle duration should not exceed 10 % of the thermal time constant t
TH
 
S3 duty with field weakening, cycle duration should not exceed 10 % of the thermal time constant t
TH
 
Voltage limit characteristic 
Limit characteristic for S1 duty 
Voltage limit characteristic with field weakening 
Rated operating point at M
N
, n
N
, I
N
 
Operating point at M
MAX
, I
MAX
, n
MAX,MMAX
 
Torque M
0
 at speed n = 1 rpm 
Figure 6-5  Schematic description of the torque-speed diagram 
 
The voltage induced in the motor winding increases as the speed increases. The difference 
between the DC link voltage of the converter and the induced motor voltage can be used to 
impress the current. 
The torque must be reduced if the voltage limit of the infeed module is reached at speed n. 
All operating points that can be achieved with the motor lie below the "voltage limiting 
characteristic".