Danfoss VLT FC 102 Programming Manual

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

Contents

20-38 Air Density Factor [%]Range: Function:100 %* [50 - 150 %] Set the air density factor forconversion from pressure to flow in% relative to the air density at sealevel at 20 °C (100% ~ 1,2 kg/m3).3.18.4 20-6* SensorlessParameters for sensorless. See also:• Parameter 20-00 Feedback 1 Source• Parameter 18-50 Sensorless Readout [unit]• Parameter 16-26 Power Filtered [kW]• Parameter 16-27 Power Filtered [hp]NOTICESensorless unit and sensorless information require set-upby MCT 10 Set-up Software with sensorless specific plugin.20-60 Sensorless UnitOption: Function:Select the unit to be used withparameter 18-50 Sensorless Readout[unit].[20] l/s[21] l/min[22] l/h[23] m³/s[24] m³/min[25] m³/h[70] mbar[71] bar[72] Pa[73] kPa[74] m WG[75] mm Hg[120] GPM[121] gal/s[122] gal/min[123] gal/h[124] CFM[125] ft³/s[126] ft³/min[127] ft³/h[170] psi[171] lb/in²[172] in WG[173] ft WG[174] in Hg20-69 Sensorless InformationRange: Function:0* [0 - 25 ] View information about thesensorless data.3.18.5 20-7* Auto-tuningPID auto-tuningThe frequency converter closed-loop controller (parametergroup 20-** FC Closed Loop) can be auto-tuned, simplifyingand saving time during commissioning, while ensuringaccurate control adjustment. To use auto-tuning, configurethe frequency converter for closed loop inparameter 1-00 Configuration Mode.Use a graphical local control panel (GLCP) to react tomessages during the auto-tuning sequence.Selecting either PID or SPC in parameter 20-79 PIDAutotuning puts the frequency converter into auto-tuningmode. The LCP then shows on-screen instructions.To start the fan/pump, press [Auto On] and apply a startsignal. The default control settings ensure that the setpointit eventually reached. For PID auto-tuning, it is possible toadjust the speed manually by pressing [▲] or [▼] to a levelwhere the feedback is around the system setpoint.CAUTIONIf the feedback goes outside the specified limits (2073and 2074) defined during auto-tune set-up, the auto-tuning is discarded. The limits also serve as applicationprotection during auto-tuning execution.NOTICEIt is not possible to run the motor at maximum orminimum speed when manually adjusting the motorspeed due to the need of increasing or decreasing themotor speed during auto-tuning.Auto-tuning introduces step changes while operating at asteady state and then monitors the feedback. For PIDcontrol, the auto-tuning feedback response defines therequired values for parameter 20-93 PID Proportional Gainand parameter 20-94 PID Integral Time are calculated.Parameter 20-95 PID Differentiation Time is set to value 0(zero). Parameter 20-81 PID Normal/ Inverse Control isdetermined during the tuning process.These calculated values are presented in the LCP and canbe either accepted or rejected. Once accepted, the valuesare written to the relevant parameters and auto-tuningmode is disabled in parameter 20-79 PID Autotuning.Depending on the system, the time required to carry outauto-tuning could be several minutes.Parameter Descriptions VLT® HVAC Drive FC 102184 Danfoss A/S © 10/2019 All rights reserved. M001000133