| CNC router design principle of frequency conversion |
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First make sure the drive CNC router installation environment; Operating temperature. CNC router is a high-power inverter internal electronic components vulnerable to temperature effects, products are generally required for the 0 ~ 55 ℃, but in order to ensure the safety, reliability, the use of leeway should be considered, the best control in 40 ℃. In the control box, CNC router mahcinbe box should normally be installed in the upper part, and strictly comply with installation requirements in product specifications, and definitely not easy to heat the heating elements or components close to the bottom of the drive CNC router installation. II. Ambient temperature. Temperature is too high and the temperature change is large, CNC engraving machine prone to condensation inside the drive, it will greatly reduce the insulation performance and may even lead to short-circuit accident. When necessary, must be increased in the drier and heater box. In water treatment, the general heavier than water vapor, if the temperature variation in the case, this problem would be more prominent. III. Corrosive gases. Use of the environment if the corrosive gas concentration, corrosion of components not only leads, printed circuit boards, but also accelerate the aging of plastic devices, reduce the insulation performance. IV. Vibration and shock. CNC router equipped with the inverter control cabinet by mechanical vibration and shock will cause poor electrical contact. Thermoelectric Huai'an to such a problem. Then in addition to improving the mechanical strength of the control cabinet, away from the source of vibration and shock sources, we must also use the seismic rubber pad fixed outside the control cabinet and the like within the electromagnetic switch vibration components. Equipment operation for some time, and should be checked and maintained. V. electromagnetic interference. CNC router at work because of the inverter rectifier and inverter, the surrounding electromagnetic interference generated a lot of these high-frequency electromagnetic waves in the vicinity of the instrument, the instrument has some interference. Therefore, the cabinet instrumentation and electronic systems, should use the metal shell, shielding the instrument drive CNC router interference. All the components should be grounded, in addition, the electrical components, equipment and instrumentation should be used in the connection between the shielded control cable, and the shield should be grounded. EMI if not properly handled, often make the whole system is not working, causing the control unit failure or damage. 2) CNC router to determine the distance between the inverter and the motor cables and wiring methods; 1.CNC engraver inverter and the motor should be as short as possible. This reduces the capacitance of the cable on the ground to reduce the interference emission sources. II. Use shielded cable control cable, power cable, or use shielded cables to the motor drive from the CNC router all in threading tube shielding. III. The motor cable should be independent of other cable routing, the minimum distance of 500mm. While avoiding long motor cables and other cables parallel lines, so as to reduce the CNC router rapid changes in the inverter output voltage generated electromagnetic interference. If the control cables and power cables cross, as far as possible so that they cross at a 90 degree angle. And the CNC router drive the analog signal line separated from the main back road alignment, even in the control cabinet also true. IV. With the CNC router drive the best selection of analog signal lines shielded twisted pair, shielded power cable three-core cable used (its size than the ordinary motor cables large file) or to comply with CNC router's user manual for the drive. 2) CNC router I. inverter main circuit diagram of control principle: the role of the reactor to prevent the CNC router is a high frequency harmonics generated by the power input circuit to return to the grid by affecting other electrical equipment, required under the CNC router The capacity of the drive to determine the need to increase the size of the reactor; filter is installed in the CNC router output of the inverter to reduce the CNC router higher harmonic output of the inverter, when the CNC router to the motor drive when the distance , you should install filters. While the CNC router has various protection functions, the drive itself, but the lack of protection is not perfect, play the main circuit breaker in the overload, lack of equal protection, selection can be in accordance with the CNC router to choose the capacity of the drive. CNC router can be used instead of the drive's own thermal overload relay. II. Control circuit: a frequency conversion of the manual switch, so that failure in the inverter frequency can be run manually cut, not add due to output voltage, frequency and frequency have a solid interlock. 3) CNC router CNC router inverter drive is properly grounded grounding is to improve the system stability, an important means to suppress noise. CNC router inverter ground terminal of the grounding resistance as small as possible, grounding conductor cross-section of not less than 4mm, the length of not more than 5m. CNC router and power inverter equipment grounding should take place separately, not common ground. Shield the signal line drive CNC router receives one end of the ground and the other end floating. CNC router between the inverter and electrical control cabinet connected. |
