Limit Switches

Question 1

Limit Switches

Answer 1

-located at the ends of the shaftway
-slowdown, normal and final limits
-normally closed and will open when activated by the car cam

Question 2

Up normal limit switch

Answer 2

-forces elevator to change direction to down
-activated once the elevator is level with the top landing

Question 3

Down normal limit switch

Answer 3

-forces the elevator to change direction to up
-activated once elevator is level with lowest landing

Question 4

Up final limit switch

Answer 4

-uppermost switch in the shaftway
-removes all power from safety circuits
-above Up Normal Limit switch
-should never be activated under normal operation

Question 5

Down final limit switch

Answer 5

-lowermost switch in the shaftway
-removes all power from safety circuits
-located below the Down Normal Limit switch
-should never be activated under normal operation

Question 6

Slowdown limit switches

Answer 6

-amount of switches will vary based on elevator speed
-slow moving elevators will have one before the Up Normal and one before the Down Normal
-located 5-7 feet before normal switches

Question 7

High speed limit switch

Answer 7

-on high speed elevators exceeding 250fpm
-added safety to slow the elevator down in emergency conditions
-the faster the car, the more high speed limits are added