The inverter duty motor nameplate shall indicate that the motor is an inverter duty motor. The type 4KTU motors are totally enclosed and fan-cooled (TEFC), as per NEMA … The standard electric motor is suitable for T4 to T6 temperature classes or the maximum +257 ˚F to +185 ˚F/+125 ˚C to +85 ˚C surface temperatures of equipment. Modern insulation materials means Class F insulation is commonly used for motor windings. With modern designs, a 'Class B' temperature rise is readily achievable. Each curve is identified by the NEMA insulation class and the allowable total temperature that is the first and the last columns shown in the table above. will not exceed surface temperature of 160°C (320°F) equivalent to Code T3C. Insulation Criteria for WEG motors driven by Variable Speed Drives The stator windings of WEG low voltage (LV) motors for the African market are wound with class “F” or class “H” insulation systems and are suitable for either direct-on-line (DOL), soft starting or variable speed drive (VSD) starting. Motor efficiency at full load: 84,8 % Motor efficiency at 3/4 load: 83,8 % Motor efficiency at 1/2 load: 80,1 % Enclosure class (IEC 34-5): IP68 Insulation class (IEC 85): F Explosion proof: no Motor protec: PTC Thermal protec: internal Length of cable: 15 m Cable type: LYNIFLEX Type of cable plug: NO PLUG Controls: Control box: not included 5/12 The inverter duty motor shall use slot fillers as required to avoid loose windings. 5. Insulation IEC 60085 Thermal class[3] IEC 60085 Thermal class[3] NEMA Class[4] NEMA/UL Letter class um ot erature ed thermal endurance (C)[3] materials 90 Y 90C > 105 er, [5] 105 A 105 A 105C > 120 er, [6] 120 E 120C > 130 and erature 130 B 130 B 130C > 155 estos lifetime C. Class I, Group D, Class II Group F & G listings. Insulation class ... NEMA Premium Motor Power Factor vs Load 60 65 70 75 80 85 90 95 25 50 75 100 115 125 150 Percent Load F EPAct only 300 hours with Class A insulation; 1800 hours with Class B insulation; 8500 hours with Class F insulation; tens of thousands of hours with Class H insulation NEMA MG 1-2011, Part 31, specifies that insulation systems for definite-purpose, low- voltage (≤ 600 V) inverter-duty motors should be designed to withstand an upper limit of 3.1 times the motor… Example - a motor operating at 180 o C will have an estimated life of. 4.0 Insulation Classes: (See chart 1 for classification) NEMA MG1 recognizes four classes of electrical insulation of the alternator: • A • B • F • H Each of these classes have different characteristics, but the accepted common feature is an anticipated minimum life expectancy of 30,000 hours. It is important to be aware that insulation classes are directly related to motor life. NEMA motor insulation classes describes the ability of motor insulation in the windings to handle heat. Classes B and F are the most common in many applications. Therefore Class F insulation with a Class B temperature rise gives us a thermal margin of 25°C, potentially increasing the life of the motor … This curve is given as a reference and uses 20 thousand hours lifetime. Note: Do not confuse the NEMA insulation classes with the NEMA motor design codes which are also given by letters. There are four insulation classes in use namely: A, B, F, and H. All four classes identify the allowable temperature rise from an ambient temperature of 40° C (104° F). Typical life expectancy versus temperature curves for NEMA Insulation Classes are shown in the figure below. The inverter duty motor insulation class shall be class F insulation and a class B temperature rise based on 40 degrees C. 6. 3 Shunt wound DC motors, 182 through 215 frames, 1/2 through 3 HP, will not exceed surface … turn insulation. Type 4KTU motors are available in a high efficiency class. T Motors with Class F insulation and 1.15 S.F.