SOS MECHANIC CERTIFICATION BRAKES
EXAM ACTUAL EXAM PAPER 2026
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
⩥ * 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.
EXAM ACTUAL EXAM PAPER 2026
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
⩥ * 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.
