Mechanic Exam Questions and Answers Rated A

Mechanic Exam Questions and Answers Rated A E=__ IR P=__ IE Pie r^2 = Area of a circle 231 in^3 /____ gal. 25.4mm/__ in. 2.2kg/ lb 3 phase rectifier output = 1.33 x input single phase output = 0.9 x input RMS (effective voltage) = 0.707 (PEAK V) TC = R x C (5)??? RPM = 60 (frequency) / (poles/2) door overlap minimum = 5/8" min door gaps maximum = 3/8" max Gibs minimum = 1/4" min Gate Switch maximum = 2" Passenger Sill to Sill ____ to ______" 1/2 to 1-1/2" Platform Lift Sill ____ to _____" 3/8" to 3/4" Moving Walk maximum = 12 degree max Governors (Car Trip Speed =______ & Overspeed Switch =______) Car trip speed 15-20% greater than contract speed. Overspeed Switch less than or equal to 90-95% of trip speed CWT (____%) Up to 10% greater than car trip speed 1) A contractor wants to raise the car speed from 100FPM to 125FPM. It currently has a 12" sheave. What size sheave is required? 15" ----Diam = 12, 12"/4=3, 25FPM=3in : 100FPM + 25FPM = 12"+3" =15" 2) An MOV (metal oxide varistor) burns out. You should replace it, but cannot read the Voltage or resistance. What should you do? Replace it with a larger MOV. (630) 3) On a Ward-Leonard circuit, the brake is set, but the motor is trying to slip through the break. What circuit is the issue? Suicide Circuit. (425) 4) You have an old DC motor and you are adding an SCR Drive. What do you do with the interpoles? Leave the interpoles alone. (425). NOTE: When adding the SCR Drive to the generator, the series loop is removed, as are the 3 resistors. Everything else stays the same. 5) A hydro runs up with no load, but does not run up with a full load. What is the issue? The relief valve is set too low. (805). 6) 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? 22" and for a 2:1 with the same issue -- 44" 7) 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? Mainline disconnect. (535) (3.2.6) 8) The contractor requests that the vertical center of the rack and pinion hoist be moved. How is this accomplished? Adjust tie downs/ wall ties (850). 9) Working pressure on a Hydro is a 400 psi. What is the correct relief valve setting? 600 psi max. (805), 400psi x 150% = 600psi 10) What must first be installed on a false car before operation? Safeties (110) note: handrails & buffers also required 11) There is a slight arcing at the brush and commutator. What actions must be taken? None. (430) Note: Heavy arcing due to light brush pressure, mechanical wear indicates heavy brush pressure. 12) If rigging gear is roped 3:1 and a beam clamp is used to lift a 6000 lb load. What is the beam capacity requirement? 18000 lb. (210). note: When rigging all blocks, rope, and clamps will be EQUAL to the lowest load rating capacity. 13) How much resistance is normally measured across a normally closed switch? 1.2 ohms 14) A car traveling in the hoistway always stops at the same point and blows a fuse. What is the problem? Traveling cable has a cut or short. 15) How is a class I (yearly) buffer test performed? At slow speed and the buffer must return in 60 sec. (555) NOTE: 5 yr Test (class 5) for car is rated load and speed and buffer returns in 90 sec., CWT is empty car at rated speed and buffer must return in 90 sec. 16) How many strain supports are required on a 350 foot raceway? 4, 1 for every 100ft. 17) How is stainless steel drilled out? Slow speed constant pressure (205) 18) What are the required amounts of clips required for wedge shackles and what is their spacings? At least 2, with the first being 4 times the diameter of the rope from the top of shackle max and the second 8 times the diameter of the rope from the first. 19) A 300ohm resistor burns out. You don't have a 300ohm resistor. What can you use to make up the resistor? TWO 600ohm resistors in parallel, (600) the resistance is the half of the highest rating in a parallel circuit. As is THREE 225ohm resistorsin parallel equal 75ohms. 20) When cutting laminated panels, which direction should the finished side face? Finished face of the material should face the cutting edge of the tool (255). The blade has a tendency to burr the back side. 21) A 480 vac step down 240 vac transformer is connected to a 3 phase rectifier. What will be the output? 320 vdc 22) How do you cut a finished floor material? Cutting blade away from the finish (255) 23) Car is loaded with 125% and sinks. Why? Slipped through the brake 24) If you find a broken or missing barricade, what do you do? Write up a formal inspection request. 25) What are the consequences of a misaligned rack and pinion hoist joint? Broken gear teeth (850) 26) If a dumbwaiter has 9 sq ft in area, 4 ft high and the rated capacity is 13.9 lb/ft3, what is the total capacity? 500 lb/ft 3 (3.2.9) NOTE: The area of the dumbwaiter is 9 sq ft max and is 4ft high, multiply that by 13.9 27) You must enter a pit where toxic fumes are present. How do you proceed? Follow proper procedure. NOTE: Confined space entry procedures now are guided by OSHA for pit entry. 28) When changing a 1:1 car rated at 600 FPM and 2000 lb capacity to a 2:1, what will the new ratings be? 300 FPM and 4000lb capacity NOTE: Halves the speed and doubles the capacity. 29) A vertical platform lift has a clearance of 1 in. How much will it have to be moved to meet code? 1/4 in. 30) A car weighs 2500 lbs with a capacity of 2500 lbs, the CWT is weighted at 40%. How much is the motor lifting at 100% load? 1500 lbs. 2500x40%= 1000 lbs 2500+1000 = 3500 = 1500 lbs 31) How must oxygen and acetylene tanks be stored? Must be stored vertically 12 ft apart, or on a cart w/ a 1/2 hr fire rated barrier between them 32) What does the code state about sill to sill distance? 3/4" to 1 1/2" spacing 33) If the sill to sill distance is 1 3/4". What will bring it into code spec? -.5" 34) When drilling a jack hole in sandy conditions what type of drill rig is required? Rotary or Auger bit (805) NOTE: Rotary - compacted soil, percussion - rocky conditions, and percussion rotary - solid rock 35)A customer does not want an escape hatch on his residential elevator. Under what conditions is this legal? Manual operation must be provided (850) 36) You wired down direction and final limit switches. Now the car only runs up. What is the problem? You wired the down direction limit wrong. 37) What are the effects of one rope sitting deeper in the sheave groove? The rope wears out and breaks faster (250) 38) There is noise coming from a freight door. The sheave is moving but the chain is not. What is the problem? Oil on the chain 39) What is the effect when you change a sling angle from 60 deg. to 30 deg. when hoisting and rigging? More tension, less capacity 40) How many points of contact must be maintained on a ladder? 3 points at all times. 41) What is the conversion formula when measuring in to mm? 25.4 in to cm 2.54 42) You open a dumbwaiter access panel and it still runs. What is the cause? Pit access switch is not working (550) 43) You perform a static load test with the pit valve in the closed position. The car sinks 6" in 15 min. What is the cause? Cylinder leak (520) 44) Where should you point a fire extinguisher when putting out a fire? at the base of the fire. 45) A car with a selective collective controller is moving to the lobby to pick up a call. An up call is put in at the second floor. What happens? Call is bypasse til the car is moving in the up direction. 46) During construction you land an escalator, but it is 10mm too low. What is wrong? Pit is too deep or column mark is off (825) 47) During construction the omega CWT rails have been damaged. Why? Overtightened from rail to bracket (215) 48) How do you handle a coworker who shows up to work intoxicated? Speak to the MIC (Foreman), union BA, or call your supervisor 49) How do you attach brackets to brick? Inserts 1/4" back from brick 50) What is a selective collective control system? A controller that allows an elevator to bypass calls in the opposite direction of travel 51) Given a generator runs at 600 RPM and has 4 poles, what is the output frequency? 600/6 sec = 10 x 20 = 20hz 52) If an XOR gat was connected to a NOR gate and attached to an AND gate with a high output, what must the input be at the XOR gate A & B? BOTH must be high. 53) Using binary logic, what DIP switches need to be in the on position of a 128 bit 30 sec timer set for 150%? 1,3,4,6=45 sec NOTE: 1 2 3 4 5 6 7 8 1 2 4 8 16 32 64 128 54) How many traveling wires are required for the following circuit? Exclude spares. BCE-----SPI/BCD-----SP2/BCD-----SP4/BCD----UR1/BCE-----UR2/BCD-----DR1/CRE-----DR2/GRD 11 +120v___________o---- o__________R2____________A__________R1__________GRD 55) There is voltage at the switch but none at point A. What is wrong? Either open R1 or R2 (635) 56) What does the square with a darkened upper triangle represent? **USE PRINT 730 TO SOLVE** DC Relay NOTE: Square with lower triangle = latching relay, and square with arrow through it = timer 57) The close door limit switch is not working. You have power from Term 35 to Term 8, no power from Term 1 to S2. Why? Door limit switch malfunction 58) Car is running normally but the buzzer will not shut off. Why? EHP 3 to 2 shorted 59) Relay STR has voltage, TRU has voltage, RU has no voltage. Why? TRU 11 9/8 60) 2nd floor PI illuminates then quickly extinguishes. Why? XI 4 and 6 61) Car will not travel to 2nd floor without a 3rd floor call, and will not go down from 3rd without a 2nd floor call. What is the problem? 2FI4/6 62) Using print #3, why wont the motor start? MOL 1 T/B 63) The step level switch on an escalator has been activated. Where do you check? Both top and bottom (825). Step switches are manual reset switches. They are activated if the step drops 1/4" or more. 64) You get a trouble call for in-op freight door. What must you do first before you begin work? Block the door open 65) You get shocked when you attempt to move a car using a temp button for the first time. Why? You forgot to hook up a ground wire (810) 66) A motor needs a sleeve bearing replaced. What type of bearing will you need? Friction bearing (420) 67) With a 7'0" platform your inside cab wall clearance is 6'8". What is the thickness or take up of the walls? 2" thick 68) You notice rouging on the governor and tail sheave. What should you do? Check the rope diameter (250) 69) Car doors are dragging on the sill. How high should they be raised to be code compliant. 1/4" 70) What type of safeties will a 300FPM car have? Wedge clamps 71) Vertical platform stopping devices? 2 switches, 15 lb max pressure 72) What type of oil do you need for sleeve bearings? SAE 20/20w (430) 73) How do you test the safety circuit? You test all switches independently 74) What is the maximum moving walk incline? 12 deg. (830) 75) How does GFI work? It detects an imbalance between the hot and neutral wires 76) Who is required to provide you with the MSDS or SDS of a solvent you're using to clean rails? Your employer (105) 77) How do emergency doors swing? outward 78) You have an EMT run with three 90's and a saddle bend. What will be required? An immediate pull box (505) 79) What is the max distance between the vertical raceway supports? 15 ft 80) What is the smallest wire permitted in an elevator install? #24 gage 81) What is the distance between strain bars? 100 ft. 82) In what section of NEC is elevator, escalator, dumbwaiters, and moving walks found? 620 83) What is the max length of a motor - generator leads can be to the controller without a raceway? 6 ft 84) What is the smallest wire allowed in a traveling cable? #20 gage 85) What is the ratio between diameter and loop of the traveler? 30 times 86) What are the most common features of load weigh? To control the generator field and inside express operation 87) What is the required by ASME on the car top? Inspection station, light, and a duplex receptacle 88) At what distance from closed does the gate switch operate? NOTE: Use your own imagination. Wife does not know this one and it was left blank. 89) What is the min of spares should be pulled? 10% 90) At what speed should the governor switch contact be set to open? 90-95% of the governor tripping speed 91) If the DC output of a three phase rectifier is lower then specified, what is the problem? On input phase is missing 92) What is the overlap min on 2 and 3 speed doors? 5/8" 93) What is the max clearance between door and sill 3/8" Note: 1/4 "min - 3/8" max 94) What is the max gap of the leading edges of center opening doors? 1/2" 95) What is the min gib (??) to sill engagement? 1/4" 96) What is the min gap sill to sill? 1/4" 97) What is the max gap sill to sill? 1/2" 98) 1 gal equals how many cubic in.? 231 99) A force of 500 lbs is applied to a plunger with an area of 25 sq in, what is the system pressure? 200 psi. 5000 lbs/25 sq in = 200 psi 100) How many gallons needed to run a 4" plunger 25 ft? 16.3 gal. NOTE: V= A(H) 101) What best describes the operation of typical hydro block valve with an elevator parked at the lobby? The DWN valve is closed, check valve closed, and the UP valve open 102) What is the definition of working pressure? Full load up pressure 103) What is the conversion from kg to lbs? kg (2.2) = lbs