Danfoss VLT HVAC Drive FC 102 Instruction Manual

Also see for VLT HVAC Drive FC 102: Operating instructions Service guide Programming guide Installation guide Installation guide

Contents

20-00 Feedback 1 SourceOption: Function:[9] Analog Input X42/1[10] Analog Input X42/3[11] Analog Input X42/5[15] Analog Input X48/2[100] Bus feedback 1[101] Bus feedback 2[102] Bus feedback 3[104] Sensorless Flow Requires set-up by MCT 10 Set-upSoftware with sensorless-specificplug-in.[105] Sensorless Pressure Requires set-up by MCT 10 Set-upSoftware with sensorless-specificplug-in.NOTICE!If a feedback is not used, set its source to [0] NoFunction. Parameter 20-20 Feedback Function determineshow the PID controller uses the three possible feedbacks.20-01 Feedback 1 ConversionOption: Function:This parameter allows a conversion functionto be applied to feedback 1.[0]*Linear No effect on the feedback.[1] Square root Commonly used when a pressure sensor isused to provide flow feedback(( flow ∝ pressure)).[2] Pressure totemperatureUsed in compressor applications to providetemperature feedback using a pressuresensor. The temperature of the refrigerant iscalculated using the following formula:Temperature = A2ln Pe + 1 − A1 − A3,where A1, A2 and A3 are refrigerant-specificconstants. Select the refrigerant inparameter 20-30 Refrigerant.Parameter 20-21 Setpoint 1 throughparameter 20-23 Setpoint 3 allow the values ofA1, A2 and A3 to be entered for a refrigerantthat is not listed inparameter 20-30 Refrigerant.[3] Pressure toflowUsed in applications for controlling the airflow in a duct. A dynamic pressuremeasurement (pitot tube) represents thefeedback signal.Flow = Duct Area × Dynamic Pressure× Air Density Factor20-01 Feedback 1 ConversionOption: Function:See also parameter 20-34 Duct 1 Area [m2]through parameter 20-38 Air Density Factor [%]for setting of duct area and air density.[4] Velocity toflowUsed in applications for controlling the airflow in a duct. An air velocity measurementrepresents the feedback signal.Flow = Duct Area × Air VelocitySee also parameter 20-34 Duct 1 Area [m2]through parameter 20-37 Duct 2 Area [in2] forsetting of duct area.20-03 Feedback 2 SourceOption: Function:See parameter 20-00 Feedback 1Source for details.[0] * No function[1] Analog Input 53[2] Analog Input 54[3] Pulse input 29[4] Pulse input 33[7] Analog input X30/11[8] Analog input X30/12[9] Analog Input X42/1[10] Analog Input X42/3[11] Analog Input X42/5[15] Analog Input X48/2[100] Bus feedback 1[101] Bus feedback 2[102] Bus feedback 3[104] Sensorless Flow[105] Sensorless Pressure20-04 Feedback 2 ConversionOption: Function:See parameter 20-01 Feedback 1Conversion for details.[0] * Linear[1] Square root[2] Pressure to temperature[3] Pressure to flow[4] Velocity to flowHow to Program VLT® HVAC Drive FC 102100 Danfoss A/S © 08/2014 All rights reserved. MG11F52266