Frequency Inverter DF51... - Moeller.com.tr

04/07 AWB8230-1541GB Motor and circuit typeTable 2: Assignment of frequency inverters to example motor circuit (fig. 11)<strong>Frequency</strong> inverters DF51-322-075 DF51-322-075 DF51-340-075 DF51-340-1K5Mains voltage 3 AC 230 V 1 AC 230 V 3 AC 400 V 3 AC 400 VMains current 5.2 A 9 A 3.3 A 5 AMotor circuit Delta Delta Star DeltaMotor current 3.5 A 3.5 A 2 A 3.5 AMotor voltage 3 AC 0 to 230 V 3 AC 0 to 230 V 3 AC 0 to 400 V 3 AC 0 to 230 VMotor speed 1430 r.p.m. 1430 r.p.m. 1430 r.p.m. 2474 r.p.m. 1)Motor frequency 50 Hz 50 Hz 50 Hz 87 Hz 1)1) Observe the motor’s limit values!Connecting motors in parallelThe DF51 frequency inverters allow parallel operation of severalmotors in U/f control mode:• U/f control: several motors with the same or different ratings.The sum of all motor currents must be less than the frequencyinverter’s rated current.• U/f control: parallel control of several motors. The sum of themotor currents plus the motors’ inrush current must be less thanthe frequency inverter’s rated current.Parallel operation at different motor speeds can be implementedonly by changing the number of pole pairs and/or changing themotor’s transmission ratio.F1Q11M1F2Q12M2Q13U1 V1 W1 U1 V1 W1 U1 V1 W1M3˜M3˜F3M3M3˜h Attention!If a frequency inverter controls a number of motors inparallel, the contactors for the individual motors must bedesigned for AC-3 operation. Do not use the mainscontactors listed in the table in the appendix (section“Mains contactors”, page 220). These mains contactorsare only designed for the mains (primary) currents of thefrequency inverter. If contactors of this size are used in themotor circuit, the contacts could weld.Connecting motors in parallel reduces the load resistance at thefrequency inverter output and the total stator inductivity, andincreases the leakage capacitance. As a result, the currentdistortion is larger than it is in a single-motor circuit. To reduce thecurrent distortion, motor reactors or sine-wave filters can beconnected at the frequency inverter output (a section “Motorreactor”, page 223 and a section “Sine-wave filter”, page 224).Example: copper wire winder• 16 motors• P = 60 W• I = 0.21 A• U = 400 V• p.f. = 0.7• Direct starting current: 2 AIf a wire breaks during winding, the corresponding motor isautomatically switched off. When the wire is rejoined, the motorcan be started up again. Only one motor can be started up at atime.<strong>Frequency</strong> inverter selection:15 motors in operation: 15 × 0.21 A = 3.15 AConnect one motor:2.00 A5.15 AFigure 13:Parallel connection of several motors to one frequencyinverterDF51-340-2K2, rated current 5.5 ADEX-LM3-008 motor reactorhThe current consumption of all motors connected inparallel must not exceed the frequency inverter’s ratedoutput current I 2N .23