Why Does a Motor Overheat When Running at Low Frequency?
2026-08-17
When a motor is driven by a VFD at low frequency, it may run much hotter than expected. Why? 1️⃣ The Motor's Cooling Fan Runs Slower For a standard induction motor, the cooling fan is usually mounted directly on the motor shaft. When the VFD reduces the frequency: Lower Frequency → Lower Motor Speed ...
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Why Do VFD IGBTs Fail? 5 Real Causes Behind Overcurrent Faults
2026-08-11
An IGBT failure is often the result, not the root cause. When a VFD trips on overcurrent—or an IGBT is damaged—simply replacing the IGBT may not solve the problem. Here are 5 common causes engineers should check: 1️⃣ Output Short Circuit A phase-to-phase short circuit, motor winding fault, or ...
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Why Does a VFD Trip on Overvoltage During Deceleration?
2026-08-07
Why Does a VFD Trip on Overvoltage During Deceleration? Have you ever noticed that a motor runs normally during acceleration and constant-speed operation, but the VFD trips on Overvoltage as soon as the motor starts to decelerate? Why does this happen? When a motor is running at high speed, the ...
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Why Does a Variable Frequency Drive (VFD) Need a Reactor?
2026-07-30
When selecting a Variable Frequency Drive (VFD), many customers focus on power rating, voltage, and control mode. However, one important component is often overlooked—the reactor. So, what exactly does a reactor do, and when should you install one? Let's take a closer look. What Is a Reactor? A ...
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Beyond VFDs: What More Can ZFENG Electric Provide for Your Industrial Automation Needs?
2026-07-27
Beyond VFDs: What More Can ZFENG Electric Provide for Your Industrial Automation Needs? When people think about variable frequency drives (VFDs), they usually think about speed control and energy saving. However, in modern industrial applications, a VFD is often only one part of a complete motor ...
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