Quote:
Originally Posted by NiHaoMike
That is true if the motor is a resistive load. But it's not. Motors draw more current to start than to run. If enough resistance is added in series, the motor will not start. Then it can draw more current than if it was running normally at full power. Obviously, that does not intentionally happen in our case. But with age, the motor bearings might tighten up such that it will fail to start on reduced current. The result is usually a blown fuse, but it's possible for the motor to be damaged by prolonged operation in "locked rotor" mode.
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True. A running motor is not a purely resistive load.
A motor draws the most current when it's not turning. That goes for universal, induction, and synchronous motors. Many high-current motors use resistors in their startup circuitry to prevent excessive current draw.
As for an automotive HVAC blower motor - if it burns up, it's relatively cheap to replace.