MicroMaster 6SE92 - ECT Sales & Service

Standard ApplicationsMICROMASTERMICROMASTER VectorMIDIMASTER Vector5. Increase P202 (Proportional Gain) until the fan speedstarts to oscillate, then reduce P202 by 5%.The system is now being controlled using only proportionalcontrol.6. Check the control loop error by subtracting the value inP210 (feedback transducer value) from the setpoint value.If the error is not acceptable then the I term will need to beset.7. When using I gain it is advisable to enter a value intoP207 (Integral Capture Range) to reduce instabilityparticularly when the error is very large, e.g. during rampup. Typically, P207 should be set to 1.5 times the errorestablished when using P Gain only.8. Set P203 (Integral Gain) to the smallest value which givesacceptably fast settling to the required value.9. If derivative gain is required, this must be set by using anoscilloscope to observe the change in feedback responseto a step change in setpoint.For this example, the value of P gain was set at 0.2 and I gain0.05. D gain was not required.Two further refinements in this design are the use of flyingstart to allow the drive to synchronise onto a spinning motorand automatic start on power up so that the drive will startwhen power is applied if the run switch is closed.System Specifications:MotorControl SystemDriveDrive Control Interface11 kW 400 V 3 phase induction motorPanel mounted switches and potentiometer, pressure sensor output used as closed loop feedbackdirect to driveMIDIMASTER Vector 6SE32 11 kW 400 VDigital input control with Run Right and Fault Reset, Analogue setpoint select4/10 Siemens DA 64 – 1998/99 (04/99)