Download WGU BIOCHEMISTRY OA CERTIFICATION SCRIPT 2026 QUESTIONS WITH SOLUTIONS GRADED A+ and more Exams Electrical Engineering in PDF only on Docsity!
WGU BIOCHEMISTRY OA
CERTIFICATION SCRIPT 2026
QUESTIONS WITH SOLUTIONS
GRADED A+
◍ A contractor wants to raise the car speed from 100fpm to 125fpm, it currently has a 12" sheave. What sheave is required?. Answer: Diam=12" 12/4=3" 25fpm=3" 100fpm + 25fpm= 12"+3"= 15" sheave
◍ A MOV (Metal Oxide Varistor) burns out. You replace it, but cannot read voltage or resistance. What should you do?. Answer: Replace it with a larger MOV
◍ You have been provided a unfamiliar brand of solvent to clean brake drums, What is the best source to determine whether it is safe to use ?. Answer: SDS
◍ A ladder needs to be extended 20' from the ground floor to the next landing. How far from the wall should the base of the ladder be ?. Answer: 5'
◍ How would you get into a pit to service the oil buffer?. Answer: Operate the Hostway access switch
◍ On a Ward-Leonard circuit the break is set, but the motor is trying to slip through the break. What is the issue?. Answer: Suicide Circuit
◍ You have an old DC motor and are adding an SCR drive, what do you do to the interpoles?. Answer: Leave the interpoles alone. When adding a SCR drive to the
generator, the series loop is removed, as are the 3 resistors. Everything else remains the same
◍ When you are installing pit equipment, which 2 items are required by AMSE A17.1 code ?. Answer: Pit switch and light switch
◍ A hydro runs up with no load, but will not run with a full load. What is the issue?. Answer: The relief valve is set too low
◍ you are working on scaffolding installing brackets, as you approach the end of the scaffolding, the plank starts to slip, what should have been done to prevent this?. Answer: End cleat should have been nailed to the underside of the plank.
◍ You are installing a car hitch plate and need to determine the correct rope drop from the machine drive sheave, how would you do this?. Answer: Drop a plumb line
◍ If a valve shown on the layout drawing is measured at 1 3/8 and the scale is a 1 to 4 ratio. What is the actual size of the valve spring ?. Answer: 5 1/
◍ Runby for a 1:1 hits the CWT buffer 4" below the top landing. CWT runby should be set at 18". How much should the ropes be shortened?. Answer: 22"
◍ You need to work on a freight door retiring cam, you LOTO the main line but there is still power on the cam. What circuit is still hot?. Answer: Door Operator Disconnect/ Main Line Disconnect
◍ The contractor requests that the vertical center of a Rack and Pinion hoist be moved. How do you do this?. Answer: Adjust Tie Downs and Wall Ties
◍ You direct your helper to get a standard rail, what size should they return with?.
◍ You are assigned to move job boxes and welding equipment to another job site, what procedure should be takin to transport gas cylinders?. Answer: Remove gauges, install protective caps and secure in vertical position.
◍ If rigging gear is roped 3:1 and a BEAM CLAMP is used to lift a 6,000lb load. What is the beam capacity?. Answer: 18,000lbs. Beam capacity is cut in half with use of clamp, when rigging all blocks, rope, and clamps will be Equal to the lowest load rating
◍ If a building exceeds 150' of travel, what is used to improve traction between the hoist ropes and the machine driver ?. Answer: compensation ropes
◍ When servicing the governor tension sheave, what switch should be used to prevent the elevator from moving?. Answer: Pit Stop Switch
◍ How much resistance is measured over a normally closed switch?. Answer: 1.2ohms. should be zero, but will never be that low
◍ You find a A/C Contactor chattering when energized, what could be the problem?. Answer: Missing or broken shading coil
◍ A car traveling in the hoistway always stops at the same spot and blows a fuse. What causes this?. Answer: Traveling cable has a cut/exposed wire or a short
◍ You are plumbing a Hoistway for a bank of elevator's, what lines are dropped first?. Answer: The two outside main rails farthest apart
◍ When filing rail joints, what is the distance you must file above and below the rail joint?. Answer: 18"
◍ While hoisting a motor generator, what should you use to stabilize the load
to prevent it from spinning?. Answer: Hoisting jack
◍ While reviewing your final layout drawing of machine room, you notice that a change in the location of the generator is needed. What is the correct action?. Answer: The MIC will submit a change to the company supervisor
◍ How is a class 1 yearly buffer test preformed?. Answer: Car at bottom landing and on inspection, jump out direction and final limits. With pit clear, run down to compress buffers, buffers should fully extend within 90 seconds. 5yr: Full load Full speed CWT: Full speed Empty
◍ How many strain supports are required on a 350ft raceway?. Answer: 4. 1 every 100ft
◍ How is stainless steel drilled out?. Answer: Slow speed and constant pressure
◍ When would you expect safeties on a counterweight ?. Answer: When the below space is occupied
◍ What is the required amount of retainer clips for wedge shackles and what is the spacing?. Answer: Minimum 2 clips. 1st at a maximum 4x the diameter of the rope 2nd at a maximum 8x the diameter above the 1st clip
◍ What is the min speed at which the governor should trip on a elevator with a contract speed of 200 FPM ?. Answer: 230 FPM min 115% 200x1.15 =
◍ since there are 231 cubic inches in a gallon, how many gallons are needed to fill a tank -which measures 4' long by 3' wide to a depth of 30". Answer: 225 gallons 4'= 48' 3'=36" 48x36x30= 51840" / 231= 224.
◍ A 300ohm resistor burns out, but you don't have another one. How can you make one?.
Answer: Slipping through the break
◍ When pulling hatchway wiring, a 10% wire spare is desirable. if the wiring requires 12-#14 AWG, 36-#16 AWG and 52-#18 AWG what is the best selection of spares?. Answer: 2-#14 AWG, 4-#16 AWG, and 6-#18 AWG
◍ if a pump operating at 2000 RPM moves a elevator 100 FPM, What RPM must the pump run to attain 150 FPM ?. Answer: 3000 RPM 100/2000 = 150/X
◍ If a hoist rope slips 0.1% how much slippage would be in a 120' run?. Answer: 1 7/16"
◍ If you find a broken or missing barricade what should you do?. Answer: Write up a formal inspection request
◍ What are the consequences of misaligned joints on a Rack and Pinion?. Answer: Broken Gear teeth. CWT derailment. Excessive wear/ crease the surface of the tube
◍ An elevator weighing 4200 lbs has a capacity of 3000 lbs. How much counterweight is required to balance the car at 40% ?. Answer: 5400 LBS elevator weight plus 40% of capacity
◍ A dumbwaiter is 9sqft in area, 4ft high, and capacity is 13.9lb/ft3. What is total capacity?. Answer: 9 x 4 x 13.9= 500lbs Max capacity
◍ How is the resistance of a conductor affected if the length and cross section is doubled ?. Answer: Resistance is not changed
◍ You must enter a pit with a toxic atmosphere, how do you proceed?. Answer: Following proper OSHA procedure with proper training and PPE
◍ A gearless machine with a 32" drive sheave roped 2:1 is leveling an elevator at 10 FPM what is the motor armature RPM ?. Answer: 24 RPM
◍ When changing a 1:1 car rated at 600fpm and 2,000lb capacity to a 2:1, what are the new ratings?. Answer: 300fpm 4,000lbs capacity Half the speed, Double the capacity
◍ How many fish plate bolts are needed to install standard main rails with 124' of travel and a 5' pit?. Answer: 112 bolts
◍ A vertical platform lift has a clearance of 1 inch. How much will it have to move to meet code?. Answer: Move in ¼ inch. Code is ¾ inch
◍ An empty hydraulic elevator with a 6" diameter jack has a line pressure of 150 psi. What is the pressure if we add an additional 2800 lb load?. Answer: 249 psi force = pressure/area
◍ A car weighs 2500lbs with a capacity of 2500lbs, the CWT is weighted at 40%, how much is the motor lifting when the car is fully loaded?. Answer: 2500(car) + 1000(40%) 3500. 5000-3500=1500lbs lifted by the machine
◍ If a elevator moves seven floors with an average height of 9'. How far does the carriage move on a selector with a 60:1 ratio?. Answer: 12.6"
◍ How must Oxygen and Acetylene tanks be stored?. Answer: Vertically, 12 feet apart, or on a cart with a ½ hour fire barrier between them
◍ if you where checking a motor field the operates on 150 vdc at 10 amps what is the motor field resistance ?. Answer: 15 ohms E/I=R
◍ If you needed to check coil voltage on the up direction , How would you connect your voltmeter ?. Answer: In parallel with the relay coil, power on.
◍ What is code for sill to sill distance?.
15 minutes. What is the problem?. Answer: Cylinder leak
◍ Where should you aim a fire extinguisher to put out a fire?. Answer: At the base of the fire
◍ Car with selective collective system is moving to the lobby to take a call, an up call is put in at the 2nd floor, what happens?. Answer: The call is bypassed until the car is traveling up
◍ During construction you land an escalator, but it is 10mm low, what is wrong?. Answer: The pit is too deep or column MARK is off
◍ During construction the Omega CWT rails have been damaged, what happened?. Answer: The Omegas were over tightened
◍ How do you handle a co-worker who shows up drunk?. Answer: Speak with MIC, Call BA, call supervisor
◍ How do you attach brackets to brick?. Answer: Inserts set back a ¼ inch into the block. Code could call for through bolts
◍ What is Selective Collective System?. Answer: Controller that allows an elevator to bypass calls in the opposite direction of travel.
◍ Generator runs at 600rpm and has 4 poles, what is the output frequency?. Answer: 20hz600/60=10 10x2=20 RPM 60 x frequency / pole/
◍ If a XOR gate was connected to a NOR gate and attached to an AND gate with a High output. What is input of the XOR gate A&B?. Answer: Both must be High
◍ Using BINARY logic, what DIP switches must be on for a 128 bit 30 second timer set at 150%. Answer: 1,3,4,6=45 seconds
◍ How many wires are needed for the following circuit? Exclude spares. BCE---SPI/BCD---SP2/BCD---SP4/BCD---UR1/BCE---UR2/BCE---DR1/CRE--- DR2/GRD. Answer: 11 wires. You do not need the duplicates
◍ How must a 9 lead 480/240 motor be wired for High Voltage?. Answer: L1(1) L2(2) L3(3) Low Voltage L1(1-7) L2(2- 8) L3(3-9) 7-4 8- 9-5 4 5 6 + 120v______0-------0_______R2________A_________R1_______GRD
◍ There is voltage at the switch, but none at A, what is wrong?. Answer: Open at R2 or R
◍ What does a square with a darkened upper triangle represent?. Answer: DC Relay darkened lower triangle=Latching Relay arrow=Timer
◍ The close door limit switch is not working, you have power at points 35-8, no voltage at 1-S2 why?. Answer: Door limit switch malfunction
◍ Car is running normally, but the Fire Service buzzer will not shut off, Why?. Answer: EHP 3-2 shorted
◍ Relay STR has voltage, TRU has voltage, RU no voltage, why?. Answer: TRU 9/8 open
◍ 2nd floor PI lights then quickly shuts off, why?. Answer: X1 4-
◍ Car will not travel to 2 without a 3 call, and will not go down to 3 without a 2 call?. Answer: 2F1 4-
◍ Sheet 3, why wont the motor start?. Answer: MOL1 T/B
◍ The step level switch on an escalator has been tripped, where do you check?. Answer: Upper and Lower Truss assemblies, trips if step sags more than
Answer: Detects an imbalance between Hot and Neutral Wires
◍ Who is required to provide MSDS or SDS for a solvent you are using?. Answer: Your employer
◍ How do emergency doors swing?. Answer: Outwards
◍ You have an EMT run with 3-90s, 2-45s, and a saddle bend. What is required?. Answer: An Intermediate pull box. 360 degrees is most bends for a continuous pipe
◍ What is the maximum distance between vertical race way supports?. Answer: 15 feet
◍ What is the smallest wire used inside travelers and outside of travelers?. Answer: #20awg #24awg
◍ What is the maximum distance between strain relief supports?. Answer: 100 feet
◍ What is the maximum length Motor-Generator leads can be outside of a controller?. Answer: 6 feet
◍ In what section of NEC is elevator, escalator, moving walks, and dumbwaiters?. Answer: Article 620
◍ What is the ratio between the loop and diameter of a round traveler?. Answer: 30 times
◍ What are the most common features of Load Weigh?. Answer: Control generator field and Inside express operation
◍ What is required by ASME on the car top?. Answer: Inspection station, Light, and Duplex outlet.
◍ At what distance from closed does the gate switch operate?.
Answer: 2 inches
◍ What is the minimum number of spares that should be pulled?. Answer: 10 %
◍ At what speed should the Gov. switch contact be set to open?. Answer: Electrical 90% of Tripping speed for 150fpm-500fpm. 95% for +500fpm
◍ If the DC output of a 3 phase rectifier is lower than specified, what is the problem?. Answer: AC fuse is blown.1 input phase is missing
◍ What is the overlap minimum on 2 & 3 speed doors?. Answer: Horizontal ½ inch Vertical 1 inch
◍ What are minimum and maximum clearance between sill and car doors?. Answer: ¼ inch Minimum 3/8-inch Maximum
◍ What is maximum leading edges for center opening doors?. Answer: ½ inch
◍ What is minimum sill to gib engagement?. Answer: ¼ inch
◍ What is minimum and maximum sill to sill gap?. Answer: ½ inch to 1 ½ inch
◍ 1 gallon equals how many cubic feet?. Answer: .134 cubic feet
◍ How many gallons are needed to run a 6" plunger 30'?. Answer: 30' to inch= 360" 3x3x3.14=28.26 28.26x360=10,173.6/231=44. gallons 4" 25': 25x12=300 2x2x3.14=12.56x300=3768/231=16.3 gallons
◍ A force of 5,000lbs is applied to a plunger with an area of 25sqin. What is system pressure?. Answer: 200psi500/25 PRESSURE=FORCE/AREA AREA=FORCE/PRESSURE
Answer: Gear oil, non-detergent, single viscosity
◍ A 75ohm resistor has blown, no replacement, how do you fix it?. Answer: 3-225ohm resistors in parallel.3-25ohm resistors in series
◍ If a Rack and Pinion hoist is not plumb, level and square. What can happen?. Answer: Set the Safeties
◍ What are extension tubes used for?. Answer: Necessary clearance for placement of concrete forms.
◍ If a hoist motor is making noise, what is the problem?. Answer: To help prevent distortion to the building AC supply, INDUCTORS can be used on AC input of a solid state drive. Inductors can serve double duty, they operate as Transformers, to match input voltage, or provide voltage isolation. As well as performing filtering on notch effect.
◍ What is the area of a 10" plunger?. Answer: Pie x Radius Squared= Area 3.14x5x5=78.
◍ The escape hatch opens in what direction?. Answer: From the outside of the car up, preventing people from getting on top of the car
◍ What drawing will show how many and location of fixtures?. Answer: The elevator Abstract. Rails, lanterns, push buttons, etc. and quantity, color, material, etc
◍ You have to order P. I. for a 12 stop building with 3 cars. 3 floors do not have P. I. what is the total number of P. I. you need to order?. Answer: 12x3=36 total floors 3 floors with no p.i.=9 36-9=27 P.I. needed
◍ If an elevator travels 1760rpm @ 60hz, how many hz needed to run at 600fpm?. Answer: 20hz 600/60=10 assume 4 poles. 10x2=
◍ You see a saw tooth wave form when using an oscilloscope out of the encoder, is that good?. Answer: NO. A perfect encoder will show a square wave. Saw tooth, when encoder has a fault
◍ What are the hand signals for crane operation?. Answer: Thumbs out=Boom out Thumbs in=Boom in Thumb up=Boom up Thumb down=Boom down Finger up clockwise=Hoist up Finger down counter clockwise=Hoist down Arm out=Stop
◍ You are working on a MOD and have to move the controller 30 feet farther away, you notice voltage drop, what can be done to increase voltage?. Answer: Use a larger gauge of wire
◍ What is the weight of normal rails? 15 full 16' rails and 2 8' rails. Answer: 16 x 16' x 15lbs = 3840lbs
◍ What is an acceptable substitute for the top rail of a barricade?. Answer: ¼ inch thick wire rope
◍ What is the proper way to test incoming voltage?. Answer: 3 phase AC using digital meter: L1-L2 L1-L3 L2-L3Hydro at pump starter. Traction at L1, L2, L
◍ When replacing a PCB in a controller what precautions must be taken?. Answer: Use a grounding wrist strap, and never remove anything with the power on
◍ Who gives you a right to a safe work space?. Answer: OSHA
◍ On an ANNUAL static load test, the car drifts down 15" in 10 minutes. There is no visible oil in the pit, where is the leak coming from?. Answer: Underground. Annual static test required for unexposed cylinders
◍ What training must be done before you can enter a pit that has been classified as a confined space?. Answer: Confined space entrant training
◍ What are 3 major factors in Hydraulic pit maintenance?. Answer: Oil, Tripping hazards, Electricity
◍ What is the tolerance for 3/8 at .003?. Answer: 372-.378 bilateral=2 direction unilateral=1 direction
◍ You are installing push buttons using snake eye screws. What type of screwdriver?. Answer: Tamper Proof
◍ You are working with EYE BOLTS, where would you check for lifting capacity?. Answer: NEVER use eye bolts for hoisting
◍ You are installing the limit cam on the car and notice that the holes are not lining up. Where do you find the correct location for the cam?. Answer: The mechanical detail drawing
◍ You are on a call and find the pulley came off the pump motor and the set screw is missing, what kind of screw would you use to replace the set screw?. Answer: Cup Screw
◍ You have to measure the outside of a pipe. What tool would you use?. Answer: Caliper Rule
◍ You are installing spring buffers on a 200fpm car, what is the minimum buffer stroke?. Answer: 4inch 100fpm 1 ½ inch 100fpm-150fpm 2 ½ inch 200fpm 4 inch
◍ You are going to replace the disc on your grinder, what test should you do before using?. Answer: Ring test
◍ How often do electrical cords need to be checked for continuity?. Answer: Every 3 months
◍ The DBG is 6'6" using 15lb rails with ¼ shim on the brackets, what is
DBB?.
Answer: 7' 1 ½" 15lb rail is 3 ½ deep so 7" total. 2 ¼" shim is ½". 6'6" + 7 ½" =7 foot 1 ½ inch
◍ How does OSHA classify a competent person?. Answer: One who is capable of identifying existing and potential hazards, and who has authorization to take prompt, Corrective measurements
◍ Car weighs 7,000lbs with a capacity of 3,500lbs. what does the CWT weigh?. Answer: 8,400lbs 3500 x 40 / 100=1,400lbs 7,000 + 1,400 = 8,
◍ You are stacking rails in a single hydro hoist way, with a rise of 48' how many rails will you need?. Answer: 6 total rails 48' / 16' = 3 3 x 2 sides = 6 rails
◍ Installing a 3,000lb capacity car, how much load will the break stop and hold?. Answer: 3,750lbs 125% of rated capacity 3,000 x 125 = 375,000 / 100 = 3,
◍ On traction elevators where are the bottom guide shoes mounted?. Answer: To the safety plank
◍ You have a hoist rated at 3,000lbs, if you use a double block to single block reeving, what would your total lifting capacity be?. Answer: 6,000lbs
◍ You need to find the DBG for the car, where would you find this information?. Answer: Final layout or Hoistway plan view drawing
◍ You are hoisting rails into the hoist way using a capstan hoist, your apprentice is having a hard time pulling in rails. What can be done to make it easier?. Answer: Add another or more wraps to the capstan hoist
◍ Responding to a call on a hydro, you determine that the 50amp circuit
