显示标签为“24v ac motor”的博文。显示所有博文
显示标签为“24v ac motor”的博文。显示所有博文

2014年10月22日星期三

The application of squirrel-cage asynchronous motor soft starter - the traditional method for motor starting


Squirrel-cage motor direct total pressure of the large current when starting the motor stator coil and produce very big impact,rat cage bar damage caused squirrel-cage winding insulation and faults,cause 8500w gasoline generator motor failure; Large current will produce a lot of heat,winding insulation damage,reducing the life of the motor.Can be used to increase the power distribution capacity or limitation of motor starting current method to solve the above problems.If only increase the distribution capacity for starting motor,it is not economic.Therefore,usually equipped with limit starting device of generator generator set motor starting current.The commonly used methods are: 1) the stator cascade reactor or resistance starting.Stator reactance starting,reduces the starting current,but also reduces the starting voltage and starting torque is reduced more.Therefore,stator reactor step- down starting applies only to the electrical motor light load motor starting. 


2) ya a delta step-down starting.Ya a delta step-down starting is also applicable to the light load motor starting,and limited to the normal operation of delta connection of the motor.Louboutin leather plant low pressure air compressor motor is to use this way. 3) the autotransformer step-down starting.Using autotransformer step-down starting,compared with the direct starting,starting voltage reduced a lot (for the rated voltage of 1/4,1/7),and the starting torque to reduce more; And autotransformer is wholesalemotor.blogspot.com not allowed to frequent starting,which limits its wide use. 4) yanbian triangle step-down starting.Yanbian triangle is made after the starting of motor,tap can't change,limiting the application of yanbian triangle starting method.These belong to step decompression starter,start-up mode and obvious shortcomings,namely the secondary impact appeared in the process of starting current.

2014年10月21日星期二

Ac voltage measurement

 In order to grasp the change situation of IC ac signal,can be used with the dB jack multimeter ac electric motor 12v 500w voltage electrical motor 24v to approximate measure of IC.Detection multimeter under ac voltage blocking,pens and insert the dB jack;For no dB jack multimeter,need in pens and concatenated a 0.1 ~ 0.5 u F condenser.The method is suitable for the working frequency is low IC,such as television video amplifier stage,field scanning circuit,etc.Due to acmotortrading.blogspot.com the inherent frequency of the circuit,waveform is different,so the measured data is an approximation,for reference only.