Mechanics Exam
** An MOV burns out, you replace it but cannot read voltage or resistance. What should you do?
ANS: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? ANS:Suicide circuit (425)
** A Hydro runs up with no load but does not run up with a full load. What is the issue? ANS: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? ANS: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? ANS:Mainline disconnect (535)
** The contractor requests that the vertical center of the Rack and Pinion hoist be moved. How is this
accomplished? ANS:Adjust Tie downs/Wall ties (805)
** Working pressure on a Hydro is 400 PSI. What is the correct Relief Valve Setting? ANS: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? ANS:15"
(125 /100 = 1.25 1.25 x 12 = 15)
** There is slight arcing at the Brushes and Commutator. What actions must be taken? ANS: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 ? ANS: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? ANS:Traveling cable has a cut or short
** How is a Class 1 (yearly) buffer test performed? ANS: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? ANS:4
One for every 100'
** How is Stainless steel drilled out? ANS:Slow speed and constant pressure (205)
** What are the required amount of clips for Wedge Shackles and what is their spacing? ANS: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? ANS: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? ANS: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?
ANS:320 VDC
480 - 33.33% = 320
** If you find a broken or missing barricade, what do you do? ANS: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? ANS: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? ANS:Broken Gear Teeth
(850) Motor not aligned.
** You enter a Pit where toxic fumes are present. How do you proceed? ANS: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? ANS:300 FPM and 4000 lb capacity.
"Halves the speed and doubles the capacity ".
** An MOV burns out, you replace it but cannot read voltage or resistance. What should you do?
ANS: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? ANS:Suicide circuit (425)
** A Hydro runs up with no load but does not run up with a full load. What is the issue? ANS: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? ANS: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? ANS:Mainline disconnect (535)
** The contractor requests that the vertical center of the Rack and Pinion hoist be moved. How is this
accomplished? ANS:Adjust Tie downs/Wall ties (805)
** Working pressure on a Hydro is 400 PSI. What is the correct Relief Valve Setting? ANS: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? ANS:15"
(125 /100 = 1.25 1.25 x 12 = 15)
** There is slight arcing at the Brushes and Commutator. What actions must be taken? ANS: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 ? ANS: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? ANS:Traveling cable has a cut or short
** How is a Class 1 (yearly) buffer test performed? ANS: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? ANS:4
One for every 100'
** How is Stainless steel drilled out? ANS:Slow speed and constant pressure (205)
** What are the required amount of clips for Wedge Shackles and what is their spacing? ANS: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? ANS: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? ANS: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?
ANS:320 VDC
480 - 33.33% = 320
** If you find a broken or missing barricade, what do you do? ANS: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? ANS: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? ANS:Broken Gear Teeth
(850) Motor not aligned.
** You enter a Pit where toxic fumes are present. How do you proceed? ANS: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? ANS:300 FPM and 4000 lb capacity.
"Halves the speed and doubles the capacity ".
