Danfoss VLT HVAC Operating Instructions Manual

Also see for VLT HVAC: Instructions Design guide Instruction Operating instructions Instruction manual

Function:Sets the time format to be used in the LCP.0-74 DST/SummertimeValue:OFF [0]Manual [2]Function:Choose how Daylight Saving Time/Summer-time should be handled. For manual DST/Summertime enter the start date and end datein par. 0-76 and 0-77.0-76 DST/Summertime StartValue:2000-01-01 00:00 –2099-12-31 23:592000-01-0100:00Function:Sets the date and time when summertime/DST starts. The date is programmed in theformat selected in par. 0-71.0-77 DST/Summertime EndValue:2000-01-01 00:00 –2099-12-31 23:592000-01-0100:00Function:Sets the date and time when summertime/DST ends. The date is programmed in the for-mat selected in par. 0-71.1-00 Configuration ModeValue:Open loop [0]Closed loop [3]Function:Open Loop [0]: Motor speed is determined byapplying a speed reference or by setting de-sired speed when in Hand Mode.Open Loop is also used if the frequency con-verter is part of a closed loop control systembased on an external PID controller providinga speed reference signal as output.Closed Loop [3]: Motor Speed will be deter-mined by a reference from the built-in PIDcontroller varying the motor speed as part ofa closed loop control process (e.g. constantpressure or temperature). The PID controllermust be configured in par. 20-**, Drive ClosedLoop or via the Function Setups accessed bypressing the [Quick Menus] button.This parameter can not be changed when mo-tor is running.1-03 Torque CharacteristicsValue:Compressor [0]Variable torque [1]Auto energy optim. compressor [2]Auto energy optim. VT [3]Function:Compressor [0]: For speed control of screwand scroll compressors. Provides a voltagewhich is optimized for a constant torque loadcharacteristic of the motor in the entire rangedown to 15 Hz.Variable Torque [1]: For speed control of cen-trifugal pumps and fans. Also to be used whencontrolling more than one motor from thesame frequency converter (e.g. multiple con-denser fans or cooling tower fans).Provides avoltage which is optimized for a squared tor-que load characteristic of the motor.Auto Energy Optimization Compressor [2]:For optimum energy efficient speed control ofscrew and scroll compressors. Provides a volt-age which is optimized for a constant torqueload characteristic of the motor in the entirerange down to 15Hz but in addition the AEOfeature will adapt the voltage exactly to thecurrent load situation, thereby reducing ener-gy consumption and audible noise from themotor. To obtain optimal performance, themotor power factor cos phi must be set cor-rectly. This value is set in par. 14-43, Motorcos phi. The parameter has a default valuewhich is automatically adjusted when the mo-tor data is programmed. These settings willtypically ensure optimum motor voltage but ifthe motor power factor cos phi requires tun-ing, an AMA function can be carried out using6. How to programme the frequency converter VLT® HVAC Drive Operating Instructions66 MG.11.A4.02 - 09.10.06. VLT® is a registered Danfoss trademark6