Technical Information AC fan - SANYO DENKI Global

Characteristics calculation method and descriptionReliability and Expected LifeA fan generally cools itself as well. The temperature rise of themotor is relatively low and the temperature rise of the grease in thebearings is also low, so expected life is longer than general someeither motors. Since the service life of bearings is a theoretical valuethat applies when they are ideally lubricated, the life of lubricant canbe regarded as expected life of the fan. The expected life of an ACfan used at an ambient temperature 60 is 25,000 hours. When themeasurement conditions are: L10 (the remaining product life inthe lifespan test is 90%), with an atmospheric temperature of 60degrees, at the rated voltage and with continuous free air. Theright table indicates the relationship between ambient temperatureand expected life estimated on the basis of our life tests and sameother tests conducted by Sanyo Denki. An accelerated life test isconducted on the basis of the concept that the expected life halvesas the ambient temperature rises by about 15 (within the operatingtemperature range of lubricant.)Expected life of AC FansExpected lifeH10 4 10521Expected life25000hL10, 602040 60 80 100 Ambient temperatureRated voltage, continuously run in a free air state, survival rate of 90%Technical MaterialNoise characteristicsNoise is average value that measured at 1 meter away from air intake side of fanthat is suspended on special frame in anechoic chamber (as per JIS B 8330).FanNoise meterAIR FLOWAcoustic radio wave anechoic chamberNoise characteristic measurement equipmentMeasuring air flow and static pressureIt is very difficult to measure air flow and static pressure. Infact, the performance curve may vary greatly according to thetype of measuring equiment.The commonly-used type of measuring equipment is a windtunnel using a Pitot tube. Sanyo Denki uses a very precisemethod using double chamber equipped with many nozzles.U-shaped tubeChamber BThrottle deviceQ 60Av¯AwhereQ = air flowm 3 /minA = cross sectional area of nozzle 4 D2 m 2 D = nozzle diameterv¯ = average air flow velocity of nozzle2g Pn m/sec : Air specific gravitykg/m 3 1.2kg/m 3 at 20 , 1 atmospheric pressureg = acceleration of gravity = 9.8m/sec 2 Pn= differential pressuremm H 2 OPs = static pressuremm H 2 OU-shaped tubeChamber ANozzleAuxiliary blowerFan to be measuredThe measuring equipment using double chanber is method tobe calculated from air flow goes through nozzle and differentialpressure between pressure of inside of chamber (Ps) andatomospheric pressure by measuring differetial pressurebetween air intake and exhaust of nozzle (Pn).Double chamber measuring equipmentConversion TableStatic pressure1mm H 2 O0.0394inch H 2 O1mm H 2 O9.8PaPascal1inch H 2 O25.4mm H 2 O1Pa0.102mm H 2 O1inch H 2 O249PaAir flow1m 3 /min35.31ft 3 /minCFM1CFM0.0283m 3 /min1m 3 /min16.67 /sec1CFM0.472 /sec1 /sec0.06m 3 /min44