Siemens MICROMASTER 440 Operating Instructions Manual

Also see for MICROMASTER 440: Getting started guide Operating instructions Getting started guide Operating instructions Operating instructions

3 Functions Issue 10/03MICROMASTER 440 Operating Instructions182 6SE6400-5AW00-0BP0The sum of both torque setpoints is limited in the same way as the torque setpointof the speed control (refer to Section 3.22.2.5). Above the maximum speed (plus 3%), a speed limiting controller reduces the torque limits in order to prevent the driveaccelerating any further.A "real" closed-loop torque control (with automatically set speed) is only possible inthe closed-loop controlled range but not in the open-loop controlled range. In theopen-loop controlled range, the torque setpoint changes the setpoint speedthrough a ramp-up integrator (integration time ~ P1499 * P0341 * P0342). This isthe reason that sensorless closed-loop torque control in the area around standstill(0 speed) is only suitable for applications which require an accelerating torquethere and not a load torque (e.g. traversing drives). For closed-loop torque controlwith sensors, this restriction does not apply.If the closed-loop torque control is active, and a fast stop command (OFF3) isoutput, then the system automatically changes-over to closed-loop speed controland the drive is braked. If a normal stop command (OFF1) is output, there is nochangeover. Instead, the system waits until a higher-level control has brought thedrive to a standstill, in order to inhibit the pulses there. This is necessary in order toallow the master and slave drives to be shut down together. For P1300 = 22 or 23,for OFF1, the drive is directly powered-down (as for OFF2).3.22.2.5 Limiting the torque setpointParameter range: P1520 – P1531P0640, r0067r1407 bit 08, r1407 bit 09Warnings -Faults -Function chart number: FP7700, FP7710All of the following limits act on the torque setpoint which is either entered at thespeed controller output for closed-loop speed control or as torque input for closed-loop torque control. The minimum is used from the various limits. This minimum iscyclically computed in the drive inverter and displayed in parameters r1538, r1539.¾ r1538 Upper torque limit¾ r1539 Lower torque limitThis means that these cyclic values limit the torque setpoint at the speed controlleroutput / torque input and indicate the instantaneously maximum possible torque. Ifthe torque setpoint is limited in the drive inverter, then this is displayed using thefollowing diagnostic parameters¾ r1407 bit 08 Upper torque limit active¾ r1407 bit 09 Lower torque limit active