Danfoss VLT FCD 311 Design Manual

Also see for VLT FCD 303: Operating instructions

Contents

Danfoss VLT FCD 311 Design Manual Manual pdf 56 page image

VLT® FCD Series Load and Motor ConfigurationSelection of configuration and torque characteristicshas an effect on which parameters can be seen inthe display. If Open loop [0] is selected, all parame-ters relating to PID regulation will be filtered out.This means that the user only sees the parametersthat are relevant for a given application.100100 Configuration(CONFIGURATION)Value:✭Speed regulation, open loop(SPEED OPEN LOOP) [0]Speed regulation, closed loop(SPEED CLOSED LOOP) [1]Process regulation, closed loop(PROCESS CLOSED LOOP) [3]Function:This parameter is used to select the configuration towhich the frequency converter is to be adapted. Thismakes adaptation to a given application simple,since the parameters not used in a given configura-tion are hidden (not active).Description of choice:If Speed regulation, open loop [0] is selected, nor-mal speed control is obtained (without feedbacksignal) with automatic load and slip compensation toensure a constant speed at varying loads. Compen-sations are active, but may be disabled in parameter134 Load compensation and parameter 136 Slipcompensation as required.If Speed regulation, closed loop [1] is selected, bet-ter speed accuracy is obtained. A feedback signalmust be added, and the PID regulator must be set inparameter group 400 Special functions.If Process regulation, closed loop [3] is selected, theinternal process regulator is activated to enable pre-cise regulation of a process in relation to a givenprocess signal. The process signal can be set to therelevant process unit or as a percentage. A feed-back signal must be added from the process and theprocess regulator must be set in parameter group400 Special functions.101101 Torque characteristic(TORQUE CHARACT)Value:✭Constant torque(CONST ANT TORQUE) [1]Variable torque low(TORQUE: LOW) [2]Variable torque medium(TORQUE: MED) [3]Variable torque high(TORQUE: HIGH) [4]Variable torque low with CT start(VT LOW CT START) [5]Variable torque medium with CT start(VT MED CT START) [6]Variable torque high with CT start(VT HIGH CT START) [7]Special motor mode(SPECIAL MOTOR MODE) [8]✭ CT = Constant torqueFunction:This parameter enables a choice of principle foradaptation of the U/f ratio of the frequency converterto the torque characteristic of the load. See par. 135U/f ratio.Description of choice:If Constant torque [1] is selected, a load-dependentU/f characteristic is obtained, in which output voltageand output frequency are increased at increasingloads in order to maintain constant magnetization ofthe motor.Select Variable torque low [2], Variable torquemedium [3] or Variable torque high [4], if the load issquare (centrifugal pumps, fans).Variable torque - low with CT start [5], - medium withCT start [6] or high with CT start [7], are selected ifyou need a greater breakaway torque than can beachieved with the three first characteristics.NB!:Load and slip compensation are not activeif variable torque or special motor mode havebeen selected.✭ = factory setting. () = display text [] = value for use in communication via serial communication portMG.04.A1.02 - VLT is a registered Danfoss trade mark56