KEB COMBIVERT F5-A User Manual

Torque display and -limiting
© KEB, 2012-10 COMBIVERT F5-A, -E, -H Page 7.8 - 5
7
Picture 7.8.2.2a Field weakening range 1/x reduction
Istfrequenz [U/min]
Moment [Nm]
dr.17dr.18 2 * dr.18
dr.15
dr.16
0,5 * dr.16
1 / x Absenkung
ds.03 "Feldschwächkennlinie" = 0: aus
The "max. torque FI" (dr.15) is depending on the maximum inverter current and can not be changed.
At default setting the maximum torque in the eld weakening is reduced to a 1/x function - because of ux
reduction.
The physical breakdown torque characteristic of the motor is a quare characteristic, i.e. also the maximum
active power in the eld weakening range must become smaller.
The square limiting characteristic must be activated if the motor shall be driven to its limits. This is done with
value 2 in point "eld weakening characteristic" of parameter dS.03 „current/torque mode“.
dS.03: Current-/torque mode
Bit Meaning Value Explanation
1
Field weakening characte-
ristic
0: off
Activation of the active current limitation in the
eld-weakening range
2: on
The limiting characteristic is adapted to the motor with parameter dr.16 „DASM max torque corn. sp“ .
dr.16 = breakdown torque of the motor (at speed dr.18) - safety reserve
Example:
a motor shall have the following rated data:
rated speed: 1470 rpm rated frequency = 50Hz
rated torque 36Nm M
rated
/ M
breakdown
= 2.5
selected value for DASM eld weakening speed (dr.18): 1500 rpm
Data sheet value for breakdown torque of the motor at rated
frequency:
2.5 * 36Nm = 90Nm
Safety reserve 25% = 22.5 Nm
dr.16 „DASM max torque corn. sp“ = 90Nm – 22.5Nm = 67.5Nm

KEB COMBIVERT F5-A Specifications

General

Brand	KEB
Model	COMBIVERT F5-A
Category	Control Unit
Language	English