Why does a bent louver actuator crank arm lock the blades?

Do not keep powering a jammed actuator. Verify blade movement by hand, correct the linkage/crank arm, and replace bent hardware before commissioning.

['If an actuator hums but the blades stay frozen, the problem may be linkage alignment, a bent crank arm, a jammed torque bar, or frame distortion-not the controls alone.', 'Disconnect power/control as required, manually verify blade travel, and inspect the linkage. Replace bent hardware or reseat the linkage on the proper flat/shaft position, then cycle the actuator only after the blades move freely.']

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