ELEVATOR 245 250 PRACTICE QUESTIONS
AND DETAILED SOLUTIONS
◉ Lula: Limited use/Limited Access (Example Wheelchair Lifts)
Max Rise 25'
Max Speed 30 Ft/Min
Max Capacity 1400 Lbs.
Max Platform Area 18 Sq/Ft.
Residential Elevator:
Max Rise 50 '
Max Speed 40 Ft/min
Max Capacity 940 Lbs.
Max Platform Area 19 Sq/Ft
840 Pg 2
Dumbwaiters:
Platform limited to 9 Sq/Ft
Inside height is limited to no more than 4 Feet
Capacity is limited to 500Lbs
No Riders
Answer: Read Lula and Dumb waiters
,545 Pg 1
◉ You never get on top and you work only partially in with the main
line OFF
Answer: If you get on top of Dumbwaiter what must be done?
545 Pg 14
◉ Notes:(Pi) π is 3.1416 and 231 Cubic inches to the Gallon
Area:
Remember to ÷ 6" ÷ 2 = 3 to get Radius
Area = π∙ r²
Area = 3.1416 x 3 x 3 = 28.27 inches or 3.146 x 9 = 28.27
Volume
Multiple are times height to solve for Volume
V = A∙H
V = 28.27 x 300 (25" feet x 12" = 300)
V = 8481 Cubic Inches
Since we already know there are 231 cubic inches to the gallon
8481 ÷ 231 = 36.71 Gallons
,Answer: PSI Formula and Gallons (Example) How much oil to move a
6" jack 25'
815 Pg 10
◉ Relief Valve :
Must be tested Annually
Its is simply Pressure relief (If car strikes obstruction,Overloaded
Car,Car hits stop ring)
If set to light Car may not move!
Check Valve:
It is simply a one way valve permitting oil to flow in one direction
Up Valve:
The most complicated valve in system
Controls Up Start and acceleration to high speed, up slow down, up
leveling speed, and up stopping.
Down Valve:
Because the elevator is not running when on the down direction the
down valve depends on system pressure.
Bypass and Relief Valve:
Have been combined into one
Answer: Valve Operation
, 815 Pg 16,17
◉ Simply:
In a Inverting Op Amp (INPUT) is supplied to the Negative
In a Non Inverting Op Amp (INPUT) is supplied to Positive
Answer: Amplifiers (Inverting and Non Inverting)
640 Pg 11
◉ Minimum is 2 switches 15 lbs. and must stop the lift within 2"
Answer: In a vertical lift how many sensors are required (Pan
Switches)
845 Pg Unknown
◉ SCRs are used in DC door motor control and more commonly in
Direct Drives (Replacing DC Generators)
AND DETAILED SOLUTIONS
◉ Lula: Limited use/Limited Access (Example Wheelchair Lifts)
Max Rise 25'
Max Speed 30 Ft/Min
Max Capacity 1400 Lbs.
Max Platform Area 18 Sq/Ft.
Residential Elevator:
Max Rise 50 '
Max Speed 40 Ft/min
Max Capacity 940 Lbs.
Max Platform Area 19 Sq/Ft
840 Pg 2
Dumbwaiters:
Platform limited to 9 Sq/Ft
Inside height is limited to no more than 4 Feet
Capacity is limited to 500Lbs
No Riders
Answer: Read Lula and Dumb waiters
,545 Pg 1
◉ You never get on top and you work only partially in with the main
line OFF
Answer: If you get on top of Dumbwaiter what must be done?
545 Pg 14
◉ Notes:(Pi) π is 3.1416 and 231 Cubic inches to the Gallon
Area:
Remember to ÷ 6" ÷ 2 = 3 to get Radius
Area = π∙ r²
Area = 3.1416 x 3 x 3 = 28.27 inches or 3.146 x 9 = 28.27
Volume
Multiple are times height to solve for Volume
V = A∙H
V = 28.27 x 300 (25" feet x 12" = 300)
V = 8481 Cubic Inches
Since we already know there are 231 cubic inches to the gallon
8481 ÷ 231 = 36.71 Gallons
,Answer: PSI Formula and Gallons (Example) How much oil to move a
6" jack 25'
815 Pg 10
◉ Relief Valve :
Must be tested Annually
Its is simply Pressure relief (If car strikes obstruction,Overloaded
Car,Car hits stop ring)
If set to light Car may not move!
Check Valve:
It is simply a one way valve permitting oil to flow in one direction
Up Valve:
The most complicated valve in system
Controls Up Start and acceleration to high speed, up slow down, up
leveling speed, and up stopping.
Down Valve:
Because the elevator is not running when on the down direction the
down valve depends on system pressure.
Bypass and Relief Valve:
Have been combined into one
Answer: Valve Operation
, 815 Pg 16,17
◉ Simply:
In a Inverting Op Amp (INPUT) is supplied to the Negative
In a Non Inverting Op Amp (INPUT) is supplied to Positive
Answer: Amplifiers (Inverting and Non Inverting)
640 Pg 11
◉ Minimum is 2 switches 15 lbs. and must stop the lift within 2"
Answer: In a vertical lift how many sensors are required (Pan
Switches)
845 Pg Unknown
◉ SCRs are used in DC door motor control and more commonly in
Direct Drives (Replacing DC Generators)