frequency changer การใช้

• Frequency changers are typically used to control the speed of motors, primarily pumps and fans.
• With the advent of solid state electronics, it has become possible to build completely electronic frequency changers.
• The device was generically referred to as a " frequency changer " or just " mixer ".
• They were considered durable for their time ( even the AC / TP frequency changer, which was normally problematic ).
• Remnant fragments of older systems may be tied to the standard frequency system via a rotary converter or static inverter frequency changer.
• This motor-generator combination can provide a frequency changer function as well as phase conversion, but requires two machines with all their expenses and losses.
• The symbol you want to use is from IEEE Std 315A-1986, clause 25.4 . 1 " Frequency changer, changing from f1 to f2 ".
• A 25 50 Hz frequency changer was installed at White Bay in 1939, allowing power generated at the two railway power stations to be fed into the Sydney County Council's 50 Hz grid as required.
• Many exceptions existed, generating stations were dedicated to power or light by the choice of frequency, and rotating frequency changers and rotating converters were particularly common to feed electric railway systems from the general lighting and power network.
• Included in this portion of the syllabus are thermionic emissions with their characteristic curves, diodes, triodes and multi-electrode valves; and the use of valves as rectifiers, oscillators, amplifiers, detectors and frequency changers, stabilisation and smoothing.
• Rotating-machine frequency changers used to convert between 25 Hz and 60 Hz systems were awkward to design; a 60 Hz machine with 24 poles would turn at the same speed as a 25 Hz machine with 10 poles, making the machines large, slow-speed and expensive.