Panasonic M41A1G4L Operating Instructions Manual

Contents

– A-34 –Panasonic Corporation Electromechanical Control Business Divisionindustrial.panasonic.com/ac/e/ © Panasonic Corporation 2018 AQCTB02E 201806-E – A-35 –Panasonic Corporation Electromechanical Control Business Divisionindustrial.panasonic.com/ac/e/ © Panasonic Corporation 2018 AQCTB02E 201806-EHandling instructionsTerminologyGear reduction ratioA ratio of the gear head with which the gear head reduces the motor speed. Panasonic offers two groups of gearreduction ratio: one is for 3, 5, 7.5, 12.5, 15 ... and the other is 3.6, 6, 9, 15, 18 .... which are 1.2 times theprevious group so that you can obtain approx. the same output speed for both 50 and 60 Hz. When it isnecessary to fine adjust the speed smoothly use a variable speed motor and controller.Heat generation and insulationWhen a current runs through the motor, heat is generated as well. This heat generation is caused by an electricalloss and mechanical loss. An electrical loss consists of (1) copper loss which is generated in the charged partdue to the resistance of the coil or conductor, and (2) iron loss which is generated in the iron portion of the motordue to the resistance of the iron portion while the magnetic flux crosses them. Mechanical loss is caused byfriction loss of the bearing and brake lining.Part of this heat generation accumulated to the motor and other is dissipated to outside of the motor throughradiation, convection and conduction. The difference between the generated heat and dissipated heat makes themotor temperature rise, and is called heat run or temperature rise of the motor.The hottest part on the motor is winding. Insulation used to protect the winding must be kept at a temperaturebelow its maximum allowable temperature. Panasonic small geared motor is provided with the heat resistanceclass 120 (E) insulation when it is used in Japan, or class 130 (B) insulation when used outside Japan.The class 120 (E) insulation will withstand temperature up to 120 ˚C.When the heat resistance class 120 (E) insulation is used, the reduced maximum temperature limit on the motorframe 90 ˚C, at the 40 ˚C room temperature (max. temperature specified by JIS). This motor frame temperaturewill decrease to 70 ˚C at 20 ˚C room temperature. The maximum temperature limit is 50 K (deg) when measuredon the frame.Transmission efficiencyEfficiency with which motor torque is increased by the gear head, and described in %. This efficiency isdetermined by the bearing, friction of the gear tooth and resistance of lubricating oil. In general, this efficiency isapprox. 90% per stage of the gear.For example, 81 % for 2 stage configuration, and then decreases to 75 %, 70 %, 65 % as the number of stagesincreases. (In the case of metal gear head, this efficiency is approx. 85 % per stage of the gear.)Maximum permissible torqueMaximum load torque which can be applied to the output shaft. This is determined by the mechanical strengthsuch as material of gear head, gear teeth and bearing and the size of gear head as well as the reduction ratio.Service factorCoefficient which is used to estimate the service life of the gear head.This value is generally derived from experience and based on type of the load and operating conditions.90 (Y)105 (A)120 (E)130 (B)155 (F)–60 K (deg)75 K (deg)80 K (deg)100 K (deg)• Type and temperature of insulationMeasurement of temperature riseThere are two methods to measure the temperature rise of the motor. One is to use a thermometer orthermocouple which is fixed on the center of the motor frame. The other method determines the temperature bymeasuring winding resistance as described below.• Thermometer method • Resistance methodThermometer Measure the winding resistance before and after the running, andthen determine the temperature rise from the following formula.K : Temperature rise at the motor winding K (deg)R1 : Winding resistance before running (W)R2 : Winding resistance after running (W)t1 : Room temperature before running (˚C)t2 : Room temperature after running (˚C)Note: This method applies only to copper winding.Overhung loadA vertical load applied to the output shaft of the gear head. This load isproduced when the mated machine is being connected through a chainbelt and the like but not produced if a coupling is used instead.Maximum value of the overhung load which is applicable to the shaft iscalled as “permissible overhung load”. This value varies depending onthe type of gear head and the distance from the edge of the shaft. Thisvalue refers to the load such as belt tension.Thrust loadAn axial load applied to the output shaft of the gear head. Maximumvalue of the thrust load which is applicable to the shaft is called as“permissible thrust load”. This value varies depending on the type of thegear head.Gear headThrust loadOverhung loadType and temperatureof insulationWindingtemperature limitWinding insulation materialmaximum allowable temperatureK = ( – 1 ) (235 + t1) + (t1 – t2)R2R190 ˚C105 ˚C120 ˚C130 ˚C155 ˚CGear head Temperature rise of motor