I'm trying to debug a dehumidifier and found that the blower wasn't working.
Taking it apart, I find... a shaded pole motor.
These things usually don't fail?
Anyway, it's apparently a 2-speed with three wires: black red and orange.
Orange apparently is common, and the speed is changed by applying 120V to red or orange. Black appears to be "high", red is "low".
I see about 7 ohms DC resistance from black-orange, 11 ohms from red-orange, and about 4 ohms from red-black.
There does not appear to be any overheating indication on the plastic covering the windings and the shaft seems to turn freely when power is disabled.
With 120VAC from Black-Orange, the motor seems to try to turn but won't turn, I feel a bit of magnetic reluctance to turn. Spinning the rotor by hand, it still refuses to continue - always slows to a stop. When power is removed, the spindle turns freely once more. It seems to spin fewer times to stop when power is applied.
I don't get why this thing won't spin? Seems really odd here...shorted winding? But it didn't overheat?
I suspect I'm in the market for a new motor most likely but this is baffling.
Taking it apart, I find... a shaded pole motor.
These things usually don't fail?
Anyway, it's apparently a 2-speed with three wires: black red and orange.
Orange apparently is common, and the speed is changed by applying 120V to red or orange. Black appears to be "high", red is "low".
I see about 7 ohms DC resistance from black-orange, 11 ohms from red-orange, and about 4 ohms from red-black.
There does not appear to be any overheating indication on the plastic covering the windings and the shaft seems to turn freely when power is disabled.
With 120VAC from Black-Orange, the motor seems to try to turn but won't turn, I feel a bit of magnetic reluctance to turn. Spinning the rotor by hand, it still refuses to continue - always slows to a stop. When power is removed, the spindle turns freely once more. It seems to spin fewer times to stop when power is applied.
I don't get why this thing won't spin? Seems really odd here...shorted winding? But it didn't overheat?
I suspect I'm in the market for a new motor most likely but this is baffling.
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