Elevator Mechanic Exam 2018, questions with accurate answers, 100% proven pass rate.

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Elevator Mechanic Exam 2018 A Latching relay: Used for call registration,direction selection or as selector relays Two types are: Set/Rest are electrical and Mechanical Latching relays Need to know... latching relay symbol, Its a box with shaded triangle in lower right hand corner. - ✔✔Which relay do you need to Order 710 Pg, 7 RPM = 60 ∙ ƒ ÷ P÷2 = Step 1. 60 x Frequency (Hz.) = Step 2. Poles ÷ 2 = Take answer 1 and ÷ by answer 2 = - ✔✔Know the formula for RPM 435 Pg. 5 If you are referring to a megohm meter, it is a test of the insulation properties of such things as electric wiring, motor windings and high power antenna mounts. We use a "megger" or "meg out" electrical wiring and equipment to see if it is shorted to ground or the frame in any way. The megger uses much higher voltages to check resistance than a normal Volt-ohm meter. Minimum resistance is 1 Meg Ohm - ✔✔Know what a Megger is and what it does 636 Pg. 13 (1) A parallel connection. (2) A resistive element placed across the terminals of an armature to bypass a portion of the current. (3) A flexible electrical conductor designed to conduct current around themechanical joint between two conductors. (4) The resistive element (Usually of very low resistance) used in parallel with a DC ammeter movement to bypass a calibrated portion of the total circuit current. - ✔✔Shunt Overloads 425 All Pages Bad Ground - ✔✔You are using a Temp Run Box and you get shocked! Why! 520 Pg. 4 The bridle hitch can consist of two,three, or four single hitches (fig. 3-22), used together to form a bridle hitch for hoisting an object A sling with two legs used to lift a 1,000 pound object will have 500 pounds of the load on each leg when the sling angle is 90 degrees. The load stress on each leg increases as the angle decreases; and if the sling angle was 30 degrees lifting the same 1,000 pound object, the load will be 1,000 pounds on each leg. Try to keep all sling angles greater than 45 degrees; sling angles approaching 30 degrees are considered extremely hazardous and must be avoided at all cost. - ✔✔Bridal Hitch 128 Pg 17 Scaffolding should be tied to the structure using #9 wire or tie-in devices. The first vertical tie should be at the maximum height of 4 times the narrowest base dimension. Additional ties are not to exceed 26' vertically. Maximum horizontal distance between ties is not to exceed 30'. - ✔✔Scaffolding, You have 32' of rise, you are using 3x5 scaffolding. Where will the tie off points be ? 140 PG. 287-288 Counterweights (Typically) are hung to counter balance the weight of the car PLUS 40% of Capacity Load. - ✔✔How much should Counterweight way?240 Pg. 14 Note: We do not use wire smaller than #20 in travelling cables and #24 outside travelers. Largest wires are feeders to Hoist /Pump motor We always have 10 % spares 10% of 52 = 5.2 On a calculator Multiply the percent 10 by the number you have and ÷ by 100 10 X 52 ÷ 100 = 5.2 - ✔✔Pulling Spare Wires (Example) 10% of 52 Wires 515 Pg.26 The correct lube must be used on chains. - ✔✔The freight door motor is spinning but the door wont move, Why? 535 Pg. 9 Lula: Limited use/Limited Access (Example Wheelchair Lifts) Max Rise 25' Max Speed 30 Ft/Min Max Capacity 1400 Lbs. Max Platform Area 18 Sq/Ft. Residential Elevator: Max Rise 50 ' Max Speed 40 Ft/min Max Capacity 940 Lbs. Max Platform Area 19 Sq/Ft 840 Pg 2 Dumbwaiters:Platform limited to 9 Sq/Ft Inside height is limited to no more than 4 Feet Capacity is limited to 500Lbs No Riders - ✔✔Read Lula and Dumb waiters 545 Pg 1 You never get on top and you work only partially in with the main line OFF - ✔✔If you get on top of Dumbwaiter what must be done? 545 Pg 14 Notes:(Pi) π is 3.1416 and 231 Cubic inches to the Gallon Area: Remember to ÷ 6" ÷ 2 = 3 to get Radius Area = π∙ r² Area = 3.1416 x 3 x 3 = 28.27 inches or 3.146 x 9 = 28.27 Volume Multiple are times height to solve for Volume V = A∙H V = 28.27 x 300 (25" feet x 12" = 300) V = 8481 Cubic Inches Since we already know there are 231 cubic inches to the gallon 8481 ÷ 231 = 36.71 Gallons - ✔✔PSI Formula and Gallons (Example) How much oil to move a 6" jack 25' 815 Pg 10Relief Valve : Must be tested Annually Its is simply Pressure relief (If car strikes obstruction,Overloaded Car,Car hits stop ring) If set to light Car may not move! Check Valve: It is simply a one way valve permitting oil to flow in one direction Up Valve: The most complicated valve in system Controls Up Start and acceleration to high speed, up slow down, up leveling speed, and up stopping. Down Valve: Because the elevator is not running when on the down direction the down valve depends on system pressure. Bypass and Relief Valve: Have been combined into one - ✔✔Valve Operation 815 Pg 16,17 Simply: In a Inverting Op Amp (INPUT) is supplied to the Negative In a Non Inverting Op Amp (INPUT) is supplied to Positive - ✔✔Amplifiers (Inverting and Non Inverting) 640 Pg 11 Minimum is 2 switches 15 lbs. and must stop the lift within 2" - ✔✔In a vertical lift how many sensors are required (Pan Switches)845 Pg Unknown SCRs are used in DC door motor control and more commonly in Direct Drives (Replacing DC Generators) SCR is a three terminal device. It basically acts as an on/off switch by pulsing the gate of the SCR with a positive voltage. Once an SCR is turned on it remains on, till anode and cathode voltages equalize or the anode and cathode are reversed biased or voltage is removed from the anode and cathode. - ✔✔SCR's 635 Pg12 A Meter with the positive lead on the Anode and the negative lead on the Cathode. A jumper is placed across the Anode and Gate as well This should show .7 Volts an indication of a Good SCR - ✔✔SCR Example: 635 Pg 14 Figure 26 In this figure 11 (Pg 7 Unit 625) it shows R¹ which controls the rate that the magnetic field builds. R¹ controls the time it takes for the brake to energize after BR contact closes. R² is in the discharge path of the brake coil. It controls the time it takes for the brake to set after the BR contact opens. R² also controls voltage spikes from the collapsing magnetic lines of the brake coil when discharging. Thus reducing spikes from reaching other parts of the circuit. - ✔✔Inductance In A DC Brake Circuit 625 Pg 7 Figure 11 Off Delay Timing Circuit: A typical door timing circuit is shown Figure 30By installing the diode across the discharge resistor(RD) The capacitor will charge fast.This ensures full door timing should the closing cycle be interrupted. When the contacts are open the capacitor discharge can not flow thru the diode but must flow thru the (RD) resistor. The timer described is OFF Delay which means the relay picks as soon as the switch or contact closes. Timing begins when the current from the feed is removed. ON Delay Timing Circuit: Figure 31 When the switch or contacts close the relay is delayed being energized until the capacitors charged.In an On Delay circuit the capacitor is connected in parallel. - ✔✔Off Delay and On Delay Timer Cicuits 710 Pg 16 When the Generator and Hoist motor armature are connected in parallel they form a closed loop.In this configuration car speed is controlled by controlling the amount of current passing thru the generator shunt field. To achieve nearly constant speed under changing loads , The Ward Leonard System of automatic armature voltage control has been in use for 1/2 century. This system also regenerates power back thru the generator to the AC mains, and an energy cost is realized. - ✔✔Ward Leonard System 425 Pg 7,17 Extension tubes and ties - ✔✔Rack and Pinion Hoist (Outside Hoist) Contractor wants to move the hoist, what do you need? 850 pg 11,12 Incorrect column line or incorrect benchmark - ✔✔Escalator is 10 inches too low, what was wrong? 825 Pg 12 Mark along the top portion of incline and bottom. (Not on curved section)Measure in between.Measure Down! Advance the escalator till the bottom line is at the top and place new line at bottom using first measurement. Continue to do this till you reach first measurement. Add all together. Note: Last measurement will be shorter than the rest. - ✔✔How do you measure an Escalator Hand Rail 835 Pg 14 (Figure 14) Moving walkway Max angle is 12° Escalator Max angle is 30° - ✔✔What is Maximum Incline of Moving Walkway? (Example) The moving walkway is at 10° in the field, how much more of an angle could it be at? 830 Pg 6 Run High Speed - ✔✔Ward Leonard System (See unit 425 Pg 18 Figure 17) Question : If all three contacts close what will happen? 425 Pg 18 Figure 17 Type B / Safeties which apply limited pressure on the guide rails during stopping interval. Continuous tension in the governor rope may or may not be required Note: Type A are for under 150 and are instantaneous type.. Type C are Type A with Oil Buffers. The stopping distance is equal to the effective stroke of the buffer. - ✔✔Safeties (What type of safeties would you have on a car that goes 300 FPM? 240 Pg 36Exposed traveling Cable - ✔✔A car keeps blowing a 3(Amp) fuse at the same point in the hoist way, What is the problem? Gear Oil, Non Detergent, Single Viscosity - ✔✔What type of oil do you put in a machine? DO NOT TORQUE them at joints Torque limits are required to maintain the shape of the rail. - ✔✔Omega Rails 220 Pg 8 3 - 225 Ohm resistors in parallel - ✔✔a 75 Ohm resistor has blow and you don't have a replacement, What can you use? You open contact E to reduce the current. Contact E opens when the brake is lifted and inserts more of the brake resistance in this series circuit, reducing the value of the brake current. This circuit places a small portion of the break resistor in series with the brake coil at the start to limit the initial current into the coil, After the coil is fully energized, the full resistor is introduced to further reduce the coil current. That is the current has to gradually build up in the coil and once it does ,it does not require as much current to keep it energized.Like a flywheel, it takes alot to get it going but once its rotating not much is needed, The final current value prevents the brake coil from saturating and thus allow it it to drop quicker and more gently when applying mechanical brake. - ✔✔Series Brake Circuit (345 Pg 8 Figure 11) 345 Pg 8 Figure 11 The hoist can go on safeties! - ✔✔If a Rack and Pinion Hoist (Outside Hoist) is not Plumb ,Level and Square what can happen? 850 Pg UnknownThe extension tubes provide necessary clearance for placement of concrete forms - ✔✔Extension tubes 850 Pg 16 To help prevent distortion to the building AC supply, INDUCTORS can be used on the AC input section of a solid state drive. These INDUCTORS can serve dbl duty. They operate as transformers to match input voltage or provide voltage isolation, as well as performing filtering on notch effect - ✔✔If a Hoist Motor is making noise, What is the problem 625 Pg 12 Figure 18 (Pi) 3.1416 x (R)radius ²(squared) Plunger diameter is 10" So you divide ÷ by 2 = 5 3.1416 x 5² (25)= 78.54 inches - ✔✔Area of a plunger 815 Pg 15 Block the doors up1 - ✔✔If you arrive at site with freight doors and one side is hanging down, what is the first thing that you do? The (AND) gate is manufactured so that its output is High ONLY with all Inputs HIGH Inputs Outputs A B C Low 0 Low 0 Low 0 Low 0 High 1 Low 0 High 1 Low 0 Low 0 High 1 High 1 High 1 The Exclusive Or Gate (XOR) is referred to as the any but not all gate.Note: That if any but not ALL of the inputs are High 1 ,Than the output will be High 1This is also called a Comparator Gate. Inputs Outputs A B C D Low 0 Low 0 Low 0 Low 0 Low 0 High 1 High 1 High 1 High 1 Low 1 High 1 High 1 High 1 High 1 High 1 Low 0 - ✔✔And Gates(And) and Exclusive Or Gates(XOR) 645 Pg 5 , 9 1 inch is equal to 2.54 cm 1 inch is equal to 25.4 mm - ✔✔Convert Inches to Millimeters 305 Pg Reference Card Step Level switches (Sometimes referred to as Sag Switches) are located within the step band of both upper and lower truss assemblies.The switches function is to prevent a step that is sagging more than 1/8 inch at the riser end of either side of the step. This is generally caused by worn, damaged or missing step wheels. This switch is manually reset to be able to run. - ✔✔Escalator Step Level Switch 825 Pg 37 The Micrometer is an instrument for measuring very small lengths using the movement of a finely threaded rotating screw. The Metric Mike is graduated and read in hundredths of a millimeter (0.01 mm) The US Mike is graduated and read in thousandths on an inch (0.001 in.) - ✔✔Micrometer Reading 170 Pg 17From the outside in, Preventing those in the cab from getting out on their own. - ✔✔The Escape Hatch opens which way? An Escape Hatch is not necessary UNLESS manual operation is not provided! - ✔✔Does a residential lift require an Escape Hatch 845 Pg 6 Elevator constructors receive the elevator Abstract. It Specifies the number of Rails,Hall lanterns,Push Buttons, Ect.... Included is details such as quantity,color,type of materials and special features unique to installation. - ✔✔What print will show you the location and how many fixtures? 175 Pg 8 12 Floors x 3 Elevators= 36 PI's - (3 from 3 floors)9 =27 - ✔✔12 Floor Building with three cars, 3 floors will not get PI's. How many PI's in total do you need to order for this job? - ✔✔If you have an elevator that goes 1760 RPM at 60Hz, What Hz do we need for it to go 600 RPM's If you see a co worker with any signs, you must take action. Talk to the mechanic in charge, call you business representative, or call your supervisor. - ✔✔If someone on the job smells of alcohol, what do you do? 120 Pg 5 Rotary (Auger Drill) It is generally used on dirt, clay, quicksand and other soft soils Rotary (Core Drill) is generally used on hard compacted soil such as clay, shale or slate and on some gravel and rocks. NOTE:For rocky conditions we use (Percussion Drilling) A more efficient way is with : For hard rock we use (Percussion Rotary) Drilling. This method uses a special bit called a Button Bit which has water and compressed air coming out of bit. - ✔✔What kind of drill method do we use in soft soil? 805 Pg 5,6,7 A perfect Encoder Wave Form will have a square wave. A Sawtooth Wave Form is produced when the rise and fall of the Encoder has a fault, - ✔✔Encoder Waveform Question : You get a Sawtooth reading on oscilloscope out of encoder. Is it good? 350 Pg 16,17 630 Pg 18,19 Raise Boom / Arm out straight to side with thumb pointed up. Lower Boom / Arm out straight to side with thumb pointed down. Extend Boom / Thumbs pointed out Retract Boom / Thumbs pointed in Hoist up / Forefinger up rotating clockwise Hoist down / Forefinger out facing down rotating counterclockwise - ✔✔Hand Signals for Moving Boom of Crane and Extend signal. 128 Pg 12The Travelling cable is connected to the car hanger to form a loop.Generally this loop should be at least 30 times the diameter of the traveling cable,The Hanger may have to be adjusted POST WISE so the loop clears the edge of the platform.The cable must have a minimum of FOUR feet vertical suspension at both the hoist-way and car hanger attachments before it starts to form into its loop. - ✔✔Traveling Cable 515 Pg 8,9 Use larger Wire - ✔✔In a modernization, they plan on moving the controller 30 Feet away which ends up resulting in a voltage drop. What do you do? The main function of the governor is to grip the governor rope. This action applies the safety stopping device on the care or the counterweight. To do this the governor must first sense an over-speed condition and than apply a braking action. Tripping Speed: Minimum tripping speed to be not less than 115% of rated speed. A 400 Ft/min car would have a minimum governor tripping speed of 400 x 1.15 = 460 Ft/min Elevators having a speed over 150Ft/min shall also have a OVER SPEED Switch When the safeties have set,they can no longer move. Its necessary to stop the machine from turning and wearing the cables and drive sheave. Therefore all elevators with type A and B Safeties shall have a Over Speed switch which will open at not more than 90% of mechanical tripping - ✔✔Governor Info: 235 Pg 5 Finished side down! - ✔✔If your cutting something with a power saw, which way does the piece you are cutting face 225 Pg 5 15 (Rails) ,16 Lbs., 2 8Ft sections 2 x 8 = 16total rails are now 16 16 lbs. x 16 ft. (Length of standard rail) = 256 Lbs. 256 Lbs x 16 =4096 - ✔✔Weight of rails Question: I you have 15 full 16 lbs. rails and two 8' sections. How much do they weigh? 1/4 Inch wire rope - ✔✔What is an ok substitute for a top rail for a barricade? 131 Pg 9 Your elevator Company Superintendent/Manager - ✔✔Who can you demand a MSDS sheet from to check chemicals in a cleaning product. 110 PG 13 Safeties - ✔✔What is needed for a False Platform 225 Pg 9 The first voltage to check is incoming voltage, usuallly three phase AC. All three voltages should be checked with an AC voltmeter using the the following procedure. 1. Line 1 to Line 2 2 Line 1 to Line 3 3.Line 2 to Line 3 On most hydraulic elevators the easiest place to take these readings is at the Pump Starter. On a traction the the wires from the disconnect switch usually terminate at three terminals on the controller that are labeled L1, L2, L3 - ✔✔How do you test incoming power 715 Pg 8The car should be run down until it strikes the buffer plunger and compresses the plunger to the limit. The car is then raised rapidly and the return of the plunger to its normal operating position is observed. If the plunger returns to its normal position within 90 Seconds, the buffer is operating satisfactorily - ✔✔Category 1 Oil Buffer test, How many seconds should it take for the buffer to fully come back. 215 Pg 10 3 Points of contact shall be maintained.. Note. Ladder should extend 3 feet above upper landing. 1/4 away from height Step ladders: Never step on top two steps. - ✔✔How many points of contact should be maintained on a ladder? 132 Pg 13 Electrostatic discharge (ESD) is commonly known a static electricity. Any form of (ESD) can destroy solid state assemblies and components.Unless directed you should handle all PSBs using a ground strap. Never Remove or install a PCB unless the power is removed from the system! - ✔✔When replacing a circuit board in a controller, what should you do after the power is Off? 645 Pg 14 OSHA - ✔✔Who gives you a rite to a safe workplace? 125 Pg 1,2 the annual cylinder test (Static Load Test) is required on unexposed cylinders.The test is performed after the relief pressure test by placing the empty car at any location and marking the location of the sill or jack to determine if there is any movement. Any movement that can not be accounted for bytemperature change,valve leakage,or visible leaks after 15 minutes indicates an underground leak. - ✔✔Static Load test (Hydraulic Elevator) A car is given a Annual Static Load Test. The car drifts down 15 inches in ten minutes with no noticeable oil leak. Where is it leaking? 820 Pg 12 Single Phase Transformers and Three Phase Transformers require 2 pieces of information: 1. The Load Line to Line voltage (V) volts 2. The Maximum Load phase current (I) current For a Single Phase Transformer (Calculation) KVA = (V x I) ÷ 1000 = For A Three Phase Transformer (Calculation) Note: (1.732) is the numerical value for the (square root of 3) or (3√) KVA = (V x I x 1.732) ÷ 1000 = KVA = (V x I x 3√) ÷ 1000= - ✔✔They give you a voltage of 480 on Primary and 216 on secondary and a current and asked which transformer you would need to order. 1KVA 1-1 , 2KVA 2-1 , 3KVA 2-1 To Answer Current is needed. also helps to know if Single Phase or Three Phase Entrant - ✔✔You are sent to an industrial plant to perform a repair in an elevator pit that has been determined to be a confined space, What general level of training must you have to perform your task? 133 Pg 14 Rotating Equipment - ✔✔Traction & Hydraulic elevator machines have many hazards, Which of the following would you consider the most dangerous? Center of Rail Measrements - ✔✔You are installing elevator machine and sheave. Where would the machine and secondary sheaves be aligned.230 Pg 17 15% 575Fpm 15% is the minimum tripping speed for safties 90 % for electronic trip device 15 x 500 ÷ 100 = 75 75 + 500 = 575 - ✔✔You are testing an elevator with a rated car speed of 500 fpm. At what minimum speed should the car safeties set. Falls - ✔✔One of the many hazards in the elevator industry is one of the most obvious dangers you could face in construction and modernization, Which of the following is that one? 105 Pg 2 The Machine Room Plan View Drawing - ✔✔You are installing Machines, Governors and Generators and need to know the location where this equipment is to be installed. Where do you Look? 175 Pg 7 42" 21" 3" toeboard - ✔✔What should the dimensions of the top rail, mid rail and toe board be on an Osha approved barricade? 131 Pg 9 5000 Lbs. - ✔✔When using personal fall protection, The life line should be made of a synthetic material or wire rope with a minimum breaking strength of ?#10 Shade - ✔✔When you are welding with less than 200 Amps. What shade glass should be in your welding hood? 120 Pg 34 Give a reasonable explanation as to what you must do and most customers will withdraw the request. - ✔✔You are working on a service job in an occupied building and the customer ask you much longer it will take before you finish and weather you can take a shortcut or something Which response would be appropriate? 155 Counterweight - ✔✔Which one of the following moving Hazards is called the silent killer? 120 Pg 6 Lock Out / Tag Out - ✔✔You are preparing to replace a resistor on a car out of service. What should you do first? Oil, Tripping and electricity - ✔✔During Hydraulic pit maintenance, what are the three major hazards? 3 Feet - ✔✔You are using a portable ladder to get from landing to the machine room level. How far above the upper level must the side rails of the ladder extend? 132 Pg 13 Less than .372 and more than .378Tolerance in one two directions is Bi Lateral while in one direction it is unilateral - ✔✔What is out of tolerance for 3/8 or .003 ? 180 Pg 11'12 Tamper Proof - ✔✔You are installing push buttons and notice they have snake eye screws. What tool must be used? 205 Pg 10 Before every pick - ✔✔When using hoisting materials, How often should they be checked for defects? We never use to hoist / Otherwise known as in line load - ✔✔You are working with eye bolts. What would you check to determine the safe working load? 210 Pg 24 last paragrah Mechanical detail Drawings - ✔✔Installing the limit cam on the car, you notice holes in different locations on the mount. Where do you find the correct measurements to set it? 175 Pg 8 Cup - ✔✔You are on a callback and you find the pulley came off the Pump Motor and the set screw is missing.What type of set screw is needed to replace the missing one? Caliper Rule - ✔✔You have been told to measure the outside diameter of a pipe. What tool would you use? 205 Pg 44" inches [Show More]

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