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MECHANICS EXAM QUESTIONS WITH CORRECT ANSWERS
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MECHANICS EXAM QUESTIONS WITH CORRECT ANSWERS
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MECHANICS EXAM QUESTIONS WITHCORRECT ANSWERS
** An MOV burns out, you replace it but cannot read voltage or resistance. What should
you do? - Answer-Replace it with a larger one (630)
* On a Ward-Leonard circuit, the brake is set but the motor is trying to slip through the
brake. What circuit is the issue? - Answer-Suicide circuit (425)
** A Hydro runs up with no load but does not run up with a full load. What is the issue? -
Answer-The relief valve is set too low (805)
** Runby for a 1:1 car hits the CWT buffer 4" below the top landing. The CWT runby
should be set at 18". How much should the ropes be shortened? - Answer-22" for 1:1.
For a 2:1 with the same issue is 44".
** You need to work on a freight door retiring cam. You LOTO the mainline disconnect
but there is still power to the cam. What circuit is still hot? - Answer-Mainline disconnect
(535)
** The contractor requests that the vertical center of the Rack and Pinion hoist be
moved. How is this accomplished? - Answer-Adjust Tie downs/Wall ties (805)
** Working pressure on a Hydro is 400 PSI. What is the correct Relief Valve Setting? -
Answer-600 PSI Max. (805)
400 psi x 150% = 600 psi
** A contractor wants to raise the car speed from 100 FPM to 125 FPM. It currently has
a 12" sheave. What size sheave is required? - Answer-15"
(125 /100 = 1.25 1.25 x 12 = 15)
** There is slight arcing at the Brushes and Commutator. What actions must be taken? -
Answer-None. (430)
"Heavy arcing is due to light brush pressure. Mechanical wear indicates heavy brush
pressure.
** How much resistance is normally measured across a normally closed switch ? -
Answer-1.2 ohms or 1 to 2 ohms
** A car traveling in the hoistway always stops at the same point and blows a fuse. What
is the problem? - Answer-Traveling cable has a cut or short
** How is a Class 1 (yearly) buffer test performed? - Answer-At slow speed and the
buffer must return in 90 seconds. (555) *(60 seconds is acceptable) (90 seconds is
code)
, 5 year test (Class 5) is car at rated load and speed. Buffer must return in 90 seconds.
CWT at rated speed and buffer must return in 90 seconds.
** How many Strain Supports are required on a 350' raceway? - Answer-4
One for every 100'
** How is Stainless steel drilled out? - Answer-Slow speed and constant pressure (205)
** What are the required amount of clips for Wedge Shackles and what is their spacing?
- Answer-At least 2, with the first being 4 times the diameter of the rope from the top of
shackle.
Second is 8 times the diameter of the rope from the first.
** Car is loaded with 125% and sinks. Why? - Answer-Slipped through the brake.
** A 300 Ohm resistor burns out. You don't have a 300 Ohm resistor to replace it. What
can you use to make up the resistor? - Answer-2 600 Ohms resistors in Parallel. "The
resistance is half of the highest rating in a parallel circuit.
3, 225 Ohm resistors in parallel equal 75 Ohms.
** A 480 VAC Step Down Transformer is connected to a 3 phase rectifier. What will the
output be? - Answer-320 VDC
480 - 33.33% = 320
** If you find a broken or missing barricade, what do you do? - Answer-Write up a formal
inspection request.
** If a Dumbwaiter has 9 square feet in Area,
4 ' High and the rated Capacity is 13.9 lb/ft3, what is the total capacity? - Answer-500
lb/ft3.
"The area of a Dumbwaiter is 9 sq' max and is 4' High. Multiply that by 13.9.
9x4 = 36. 36 x 13.9 = 500
** What are the consequences of a misaligned Rack and Pinion hoist joint? - Answer-
Broken Gear Teeth (850) Motor not aligned.
** You enter a Pit where toxic fumes are present. How do you proceed? - Answer-
Follow proper procedures.
"Confined Space entry procedures are now guided by OSHA for pit entry".
** When changing a 1:1 car rated at 600 FPM and 2000 lb capacity to a 2:1, what will
the new ratings be? - Answer-300 FPM and 4000 lb capacity.
"Halves the speed and doubles the capacity ".
** A "Vertical" platform lift has a clearance of 1". How much will it need to be moved to
meet code? - Answer-Deduct 1/4".
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