Siemens 420 manual Current limiting Imax controller, Imax controller setpoint

3 Functions Issue 07/04

3.21.1.5Current limiting (Imax controller)

Parameter range:	P1340 – P1344
	r0056 bit 13
Warnings	A0501
Faults	F0001
Function chart number:	FP6100

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 fImax (r1343) or the drive inverter output voltage by VImax (r1344). By either reducing the output frequency or the output voltage, this reduces the load on the drive inverter and protects against continuous damage.

				Imax ctrl prp gain			Imax ctrl int time
					0.000 ... 0.499	0.000 ... 50.000 [s]
					P1340.D (0.000)		P1346.D (0.300)
					Kp		Tn
			Motor temperatur				fI_max	CO:Imax ctrl Foutp
			Inverter temperatur					r1343
			i2t inverter
Motor ovl fact [%]			Imax controller setpoint
10.0 ... 400.0	[%]		−	+
P0640.D (150.0)					Kp		Tn
	Motor ovl fact [%]		r0067				UI_max	CO:Imax ctrl Voutp
			CO: Outp cur limit [A]
	10.0 ... 400.0	[%]						r1344
	P0640.D (150.0)		Current feedback
			r0068
			CO: Output current [A]
					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)

Fig. 3-64 Imax controller

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).

MICROMASTER 420	Operating Instructions
150	6SE6400-5AA00-0BP0