Current Limiting (Imax Controller) - Siemens MICROMASTER 420 Operating Instructions Manual

3 Functions
3.21.1.5

Current limiting (Imax controller)

Parameter range:
Warnings
Faults
Function chart number:
Our drive inverters have, in the V/f characteristic mode, a current limiting controller
(Imax controller, refer to Fig. 3-64). This controller avoids overload conditions. This
controller protects the drive inverter and the motor against continuous overload
conditions by automatically reducing the drive inverter output frequency by f
(r1343) or the drive inverter output voltage by V
output frequency or the output voltage, this reduces the load on the drive inverter
and protects against continuous damage.
Motor ovl fact [%]
10.0 ... 400.0 [%]
P0640.D (150.0)
Fig. 3-64
NOTE
A reduction in the frequency only reduces the load if the load decreases at lower
speeds (e.g. square-law torque-speed characteristic of the driven load).
150
P1340 – P1344
r0056 bit 13
A0501
F0001
FP6100
Motor temperatur
Inverter temperatur
i 2 t inverter
Imax controller setpoint
r0067
Motor ovl fact [%]
CO: Outp cur limit [A]
10.0 ... 400.0 [%]
P0640.D (150.0)
Current feedback
r0068
CO: Output current [A]
Imax controller
(r1344). By either reducing the
Imax
Imax ctrl int time
Imax ctrl prp gain
0.000 ... 50.000 [s]
0.000 ... 0.499
P1346.D (0.300)
P1340.D (0.000)
Kp Tn
f
I_max
+
Kp Tn
U
I_max
Imax ctrl prp gain Imax ctrl int time
0.000 ... 5.499 0.000 ... 50.000 [s]
P1345.D (0.250) P1346.D (0.300)
MICROMASTER 420 Operating Instructions
6SE6400-5AA00-0BP0
Issue 07/04
Imax
CO:Imax ctrl Foutp
r1343
CO:Imax ctrl Voutp
r1344