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建筑樓宇、工業(yè)制造及機械配套等工程項目
在生活和生產中,經常使用漏電開關,但變頻器有時使用較少。在車間安裝開關時,大多數(shù)制造商經常使用漏電開關作為主開關。當使用變頻控制時,問題就展現(xiàn)出來了,漏電開關使用一段時間以后總會出現(xiàn)跳閘現(xiàn)象。
Leakage switches are often used in daily life and production, but frequency converters are sometimes used less. When installing the switch in the workshop, most manufacturers often use the leakage switch as the main switch. When the frequency conversion control is used, the problem arises. After the leakage switch is used for a period of time, there will always be tripping.
個人經驗是,在安裝帶變頻器的機器時,必須排除漏電或單獨使用塑料外殼斷路器,以免開關跳閘。引起錯誤的行動!
Personal experience is that when installing machines with frequency converters, leakage must be eliminated or plastic case circuit breakers should be used alone to avoid switch tripping. Actions that cause errors!
30毫安的漏電流不能用在變頻器上。100mA的泄漏電流不能用來保護人身安全。主要原因是變頻器的漏電流會導致變頻器誤動作。如果必須安裝泄漏電流,應選擇100mA,以防止線路絕緣因火災損壞。
Leakage current of 30 mA cannot be used in frequency converter. 100 mA leakage current can not be used to protect personal safety. The main reason is that the leakage current of the converter will lead to the wrong operation of the converter. If leakage current must be installed, 100 mA should be selected to prevent line insulation from being damaged by fire.
使用變頻器時,不得使用漏電保護器。這是使用變頻器的主要原則。
When using frequency converter, leakage protector should not be used. This is the main principle of using frequency converter.
有些客戶在使用變頻器時會為變頻器選擇相應的漏電保護器。最終結果是變頻器將一起移動,漏電保護器將運行,系統(tǒng)根本不運行。
Some customers will choose the appropriate leakage protector for the converter when using the converter. The end result is that the converter will move together, the leakage protector will run, and the system will not run at all.
為什么呢?
Why?
漏電保護器的原理是零級電流為零。使用變頻器時,零級電流不能為零。
The principle of leakage protector is zero current. When using the frequency converter, the zero-order current can not be zero.
變頻器的輸出側是pwm波。在電動機電纜和地面之間有一條長電纜的電容效應。當使用帶有屏蔽層的電纜時,電容效應更為明顯。在變頻器工作時,電容器充電放電,并有電流通過電容器流入地球,然后變頻器從入口線上的地線回流,形成電流回路。如果進口側使用泄漏保護器,它將起到切斷系統(tǒng)的作用。
The output side of the converter is the PWM wave. There is a capacitive effect of a long cable between the motor cable and the ground. When using cable with shielding layer, the capacitance effect is more obvious. When the frequency converter works, the capacitor is charged and discharged, and the current flows into the earth through the capacitor. Then the frequency converter flows back from the line on the entrance line to form a current loop. If the leakage protector is used on the import side, it will cut off the system.
所以,不要把你的變頻器配上漏電保護器。如果你想確保安全,做好接地設備。
So don't attach your converter to the leakage protector. If you want to ensure safety, do a good job of grounding equipment.