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ELEVATOR MECHANIC EXAM-
WITH 100% VERIFIED SOLUTIONS-
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 the mechanical 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
10 X 52 ÷ 100 = 5.
Pulling Spare Wires (Example) 10% of 52 Wires 515 Pg. 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. 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 10
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 Pg 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 30 By 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
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 36 Exposed 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?
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 up 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 1 This 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.
175 Pg 8 12 Floors x 3 Elevators= 36 PI's - (3 from 3 floors)9 = 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, 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, 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.
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 = 16 total rails are now 16 16 lbs. x 16 ft. (Length of standard rail) = 256 Lbs. 256 Lbs x 16 = 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.
- 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, L How do you test incoming power 715 Pg 8 The 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
