3  Functions  Issue 10/06 
  MICROMASTER 440      Operating Instructions 
244  6SE6400-5AW00-0BP0 
The following criteria provide a basis as to when a speed actual value encoder is 
required: 
¾  High speed accuracy is required 
¾  High requirements are placed on the dynamic response 
♦ Improved control performance 
♦  Improved immunity to disturbances 
¾  The torque is to be controlled over a control range greater than 1:10  
¾  A defined and/or a changing torque has to be maintained for speeds below 
approx. 10 % of the rated motor frequency P0310 
When it comes to entering a setpoint, the Vector control (refer to Table 3-40) is 
sub-divided into  
¾  Closed-loop speed control, and 
¾  Closed-loop torque/current control (briefly: Closed-loop torque control).  
Table 3-40  Vector control versions 
Vector control (closed-loop)  Without encoder  With encoder 
Closed-loop speed control  P1300 = 20, P1501 = 0  P1300 = 21, P1501 = 0 
Closed-loop torque control  P1300 = 20, P1501 = 1 
P1300 = 22 
P1300 = 21, P1501 = 1 
P1300 = 23 
 
When closed-loop speed control is used, the closed-loop torque control is 
secondary. This type of cascaded closed-loop control has proven itself in practice 
regarding commissioning and increased transparency.