Question 403Electricity/Electronics - Assistant Engineer70% to pass
As shown in the illustration of an electrically operated watertight door controller, how is the motor stopped automatically when the door is wedged open? Illustration EL-0115
AI Explanation
The correct answer is C) Action of door open limit switch (LSO).
When a watertight door is wedged open, the door open limit switch (LSO) is activated, which automatically stops the motor that controls the door. This is a safety feature designed to prevent the door from closing on someone or something that is obstructing the doorway.
The other answer choices are incorrect because: A) Momentarily depressing the close push button switch would not automatically stop the motor, B) The motor overload (OL) protects the motor from overheating but does not automatically stop it when the door is open, and D) The door closed limit switch (LSC) is used to stop the motor when the door is fully closed, not when it is open.
Related Questions
#401 As shown in the illustration of an electrically operated watertight door controller, what type of motor is used to open and close the watertight door? Illustration EL-0115 #402 As shown in the illustration of an electrically operated watertight door controller, how is reversal of the direction of motor rotation achieved? Illustration EL-0115 #404 By what means is the burning of controller contacts due to arcing, when opening, prevented? #405 As shown in the illustration of an electrically operated watertight door controller, how is the motor stopped automatically when the door is wedged closed? Illustration EL-0115 #406 A digital multimeter is set up as shown in the illustration to test an individual element of a three-phase immersion heater. The elements are connected across terminals 1 and 4, 2 and 5, and 3 and 6 as shown. The reading across terminals 1 and 4 is 32 ohms. The reading across terminals 2 and 5 is 32 ohms. The reading across terminals 3 and 6 as shown is "OL" ohms. What condition is indicated? Illustration EL-0216