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Appendix B - Current limits contour adjustment

The amplifier can be configured to have either continuous current limit or peak current limit or both which depend on motor velocity feedback. This function is enabled by calculating and inserting R11, R13.

The continuous current limit is speed dependent when R11 is inserted. The peak current limit is speed dependent when R13 is inserted.

The general shape of the operating envelope is given in fig. B-1

Velocity

 

 

 

N1

 

 

 

N2

 

 

 

T2

Tc

T3

Tp

Torque

Tc - Max continuous torque up to velocity N1

T2 - Continuous torque at max velocity (Nmax).

Tp - Max peak torque up to velocity N2.

T3 - Peak torque at maximum velocity.

Fig. B-1: Current limits contour

The user should derive the relations r1=N1/Nmax, r2=T2/Tc,

s1=N2/Nmax and

s2=T3/Tp from the motor data sheet.

 

R11 and R10 (for continuous limit) and/or R13/R12 (for peak limit) should be installed according to the following relations:

ISP - Rev 6/95

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Elmo ISP manual Appendix B Current limits contour adjustment, Velocity Torque