TM 5-3895-374-24-1 Recommendations for use of the motor/speed controller combination Line inductances The use of line inductances is strongly recommended in the following circumstances -mains subject to interference from other loads (interference, overvoltage), -speed controller supplied by a line with very low impedance (proximity of power transformers with more than 10 times the speed controller power), especially rf the speed controller power is > 55 kW, - installation of a large number of frequency inverters on the same line The use of these inductances provides the following advantages - increased protection against input rectifier bridge  overvoltages, - reduction of the current absorbed by the speed controller at full load the inductances recommended enable limitation of the line current to a value equal to that of the motor current, - reduction of the load on the power factor correction capacrtors, where fitted in the installation Inductances between The addition of inductances between the speed controller and the motor is recommended the speed controller in the following circumstances and the motor - speed controller and motor connected by cables > 100 meters long, - motor control in parallel, if the number is > 3, - motors with more than 6 poles, with a low power factor and stator inductance, - motor with a higher power value than the speed controll er power, - ATV-452D55S, D75N, D90N to ensure protection against short-circuits between output phases, if the speed controller-motor connection cables are < 25 meters long The use of these inductances enables reduction of - the values of the current peaks taken by the motor, - earth leakage interference currents, - radio interference created by the motor connection cables, - vibrations and motor noise Recommended The inductances recommended can be used on line and / or between the speed controlle  r and the motor three phase inductances Characteristics For speed controllers Reference 5 mH 5 A ATV-452075 (M) (N) VZ1 -L005UM50T ATV-452U15 (N) ATV-452U22 (N) 1,7mH 15A ATV-452U22M VZ1-L015UM17TT ATV-452U30 ATV-452U40 (M) (N) (S) ATV-452U55 (N) 0,8 mH 30 A ATV-452U55M VZ1-L030U800T ATV-452U75 (M) (N) (S) ATV-452D11 (N) ATV-452D15 (N) (S) 0,6 mH 40A ATV-452D11M VZ1-L040U600T ATV.452D1 8N ATV-452D22N 0,35 mH 70 A ATV-452D15M VZ1 -L070U350T ATV-452D22 ATV-452D30 (N) (S) ATV-452D37 (N) 0,17 mH 150 A ATV-452D55 (N) (S) VZ1-L150U170T ATV-452D75 (N) 0,1 mH 250A ATV-452D90 (N) VZ1-L250U100T (page 3-187)