Why does my three-phase motor draw unbalanced current across phases
Unbalanced current in a three-phase motor usually means a problem with the power supply, motor windings, or connections. Common causes include a…
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Industrial Equipment & Machinery
Practical, step-by-step fixes for industrial equipment & machinery problems — 55 published so far.
Why does my three-phase motor hum but not start when I press the button?
A three-phase motor that hums but won't start usually has a missing phase, a bad capacitor, or a seized bearing preventing rotation.…
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Why does my three-phase motor hum but not start when I press the start button?
A three-phase motor that hums but won't start usually has a missing phase, a bad capacitor, or a mechanical bind. Check for…
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Why does my three-phase motor hum but not start?
A three-phase motor that hums but won't start usually has a missing phase, a bad capacitor (if single-phase), or a mechanical bind…
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Why does my three-phase motor hum but won't start?
A three-phase motor that hums but won't start usually means one phase is missing, a starter contact is bad, or the motor…
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Why does my three-phase motor hum loudly but not turn when I press start?
A three-phase motor that hums but won't rotate typically indicates a single-phased power supply, a blown fuse, or a mechanical binding like…
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Why does my three-phase motor trip the overload relay after running for 10 minutes?
A three-phase motor that trips its overload relay after 10 minutes usually has a high-resistance connection, a failing bearing, or an undervoltage…
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Why does my three-phase motor trip the overload relay after running for 20 minutes?
A three-phase motor that trips its overload relay after 20 minutes usually has a mechanical binding, voltage imbalance, or an undersized overload…
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Why does my three-phase motor trip the overload relay intermittently during startup?
A three-phase motor trips its overload relay during startup because the motor draws excessive current due to mechanical binding, low voltage, a…
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Why does my VFD display overcurrent fault during acceleration
A VFD overcurrent fault during acceleration usually means the motor is demanding more current than the drive can supply, often caused by…
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Why does my VFD fault on overcurrent during acceleration?
A VFD faults on overcurrent during acceleration when the motor demands more current than the drive's limit, usually from too-short ramp time,…
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Why does my VFD fault on overcurrent during motor acceleration
A VFD faults on overcurrent during acceleration when the motor demands more current than the drive's limit, usually from too-short ramp time,…
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