How can devices with U.S. voltage and frequency standards be used in China?
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A large set of equipment has been introduced to the United States. Its voltage and frequency are 4.16 KV/60 Hz and 480 V/60 Hz. What kind of transition equipment is needed if it is to be transported directly to China for installation and use? What consequences might arise if it is installed and used directly? I would appreciate it if experts could provide a detailed explanation and discussion on this matter. Thank you! I am using a set of casting equipment that requires a large capacity: 4160V, with 8 motors, each weighing 330KW. The capacity for 480V/60Hz also needs to be 2000 KVA – it’s really frustrating!
I’m not sure what kind of equipment you have; let’s have a brief discussion on it. For the low-voltage section, 380/50HZ can generally be used directly. The overall efficiency will just decrease, but there are no issues with the application itself. (Many imported devices can operate with 2 power supplies.) I’m not sure what you mean by the medium-voltage circuit Is it a medium-voltage device or just a transformer?
I can’t afford to give an opinion without having seen where it’s connected; it’s not clear whether an inverter needs to be installed.
Your medium-voltage motor must be equipped with a three-level direct-drive variable frequency drive from SIEMENS or ABB in order to be used in China! The rectification section is selected in accordance with domestic standards ； The inverter section is selected according to the 60HZ European and American standards ； That is, the entire frequency converter is selected according to the 60HZ standard used in Europe and America.
Taking the electric motor as an example, the effects of different voltages and frequencies on the motor are discussed: Current: Since the resistance of the motor windings is much smaller than its reactance, the current is essentially proportional to the voltage and inversely proportional to the frequency. And 380/50 is approximately equal to 460/60 (the voltage on American equipment should be 460V); therefore, the operating current of American motors in domestic systems is essentially the same. Power: Since the current is essentially equal, the motor power depends only on voltage; therefore, the power will decrease by 17%. Electromagnetic torque: essentially equal to that of the current analysis system. Motor speed: Assuming the slip rate remains constant, the motor speed is directly proportional to the frequency; therefore, the speed will also decrease by about 17%. Temperature rise: As the frequency decreases and the speed drops, the iron loss of the motor increases slightly; furthermore, if ventilation is inadequate, the temperature rise will also increase, by about 2 degrees generally. Based on the above analysis, 460V and 60HZ can be used directly and can meet the process requirements in most cases. There are some actual operational examples in China; for instance, the welding production line at FAW Jetta is equipped entirely with American machinery and has been in use for nearly 20 years.
I am using a set of casting equipment that requires a large capacity: 4160V, with 8 motors, each weighing 330KW.
:Weren’t technical agreements discussed back then? Still didn’t notice this. The voltage and frequency in some parts of North America and the Middle East are different from those used in China. . The European standard is the same as that in China. .
The introduction on the 5th floor was really good; I learned a lot from it.
Are there any peers in China who have used similar equipment? Please help introduce them.
Changing the frequency of the power grid is relatively costly. Furthermore, a separate transformer must be selected for both high-voltage and low-voltage equipment, and it is possible to choose the appropriate voltage based on the specific requirements of the load. (These do not increase power supply costs)