Danfoss VLT AQUA Drive FC 202 Design Manual

Also see for VLT AQUA Drive FC 202: Service guide Installation guide Installation guide Operating guide Installation guide

Contents

Enclosure sizes Power Size [kW] Voltage [V] 1 cable [m] 2 cables [m] 3 cables [m] 4 cables [m]A1, A2, A4, A5 0.37–0.75 400 150 45 8 6500 150 7 4 3A2, A4, A5 1.1–1.5 400 150 45 20 8500 150 45 5 4A2, A4, A5 2.2–4 400 150 45 20 11500 150 45 20 6A3, A4, A5 5.5–7.5 400 150 45 20 11500 150 45 20 11B1, B2, B3, B4,C1, C2, C3, C4 11–90 400 150 75 50 37500 150 75 50 37A3 1.1–7.5 525–690 100 50 33 25B4 11–30 525–690 150 75 50 37C3 37–45 525–690 150 75 50 37Table 3.17 Maximum Cable Length for Each Parallel Cable3.4.7 Control Wire IsolationHarmonic interference generated by motor cabling candegrade control signals in the converter control wiring andresult in control faults. Motor cables and control wiringshould be separate. Interference effects decrease signifi-cantly with separation.• The distance between control wiring and motorcables should be more than 200 mm.• Divider strips are essential with smallerseparations or interference may be coupled in ortransferred.• Control cable shields must be connected at bothends in the same way as motor cable shields.• Shielded cables with twisted conductors providehighest attenuation. The attenuation of themagnetic field increases from around 30 dB witha single shield to 60 dB with a double shield andto approximately 75 dB if the conductors are alsotwisted.3.4.8 Motor Thermal ProtectionThe frequency converter provides motor thermalprotection in several ways:• Torque limit protects the motor from overloadindependent of the speed.• Minimum speed limits the minimum operatingspeed range, for instance between 30 and 50/60Hz.• Maximum speed limits the maximum outputspeed.• Input is available for an external thermistor.• Electronic thermal relay (ETR) for asynchronousmotors simulates a bi-metal relay based oninternal measurements. The ETR measures actualcurrent, speed and time to calculate motortemperature and protect the motor from beingoverheated by issuing a warning or cuttingpower to the motor. The characteristics of theETR are shown in Illustration 3.17.1.21.0 1.43010201006040501.81.6 2.020005002004003001000600t [s]175ZA052.12fOUT = 2 x f M,NfOUT = 0. 2 x f M,NfOUT = 1 x f M,N(par. 1-23)IMN (par. 1-24)I MIllustration 3.17 Electronic Thermal Relay CharacteristicsThe X-axis shows the ratio between Imotor and Imotornominal. The Y-axis shows the time in seconds before theETR cut off and trip. The curves show the characteristicnominal speed, at twice the nominal speed and at 0.2 xthe nominal speed.At lower speed, the ETR cuts off at lower heat due to lesscooling of the motor. In that way, the motor is protectedfrom overheating even at low speed. The ETR featurecalculates the motor temperature based on actual currentand speed.System Integration Design GuideMG20N602 Danfoss A/S © 09/2014 All rights reserved. 573 3