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Mechanics Exam
** An MOV burns out, you replace it but cannot read voltage or resistance. What should you do? - Replace it with a larger one (630)
- On a Ward-Leonard circuit, the brake is set but the motor is trying to slip through the brake. What circuit is the issue? - Suicide circuit (425) ** 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) ** 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" 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? - Mainline disconnect (535) ** The contractor requests that the vertical center of the Rack and Pinion hoist be moved. How is this accomplished? - Adjust Tie downs/Wall ties (805) ** Working pressure on a Hydro is 400 PSI. What is the correct Relief Valve Setting? - 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? - 15" (125 /100 = 1.25 1.25 x 12 = 15) ** There is slight arcing at the Brushes and Commutator. What actions must be taken? - 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? - 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?
- Traveling cable has a cut or short ** How is a Class 1 (yearly) buffer test performed? - 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? - 4 One for every 100' ** How is Stainless steel drilled out? - Slow speed and constant pressure (205) ** What are the required amount of clips for Wedge Shackles and what is their spacing? - 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? - 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? - 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. ** A 480 VAC Step Down Transformer is connected to a 3 phase rectifier. What will the output be? - 320 VDC 480 - 33.33% = 320 ** If you find a broken or missing barricade, what do you do? - Write up a formal inspection request.
Percussion = Rocky conditions Percussion Rotary = Solid rock ** A customer does not want an Escape Hatch on his residential elevator. Under what conditions is this legal? - Manual Operation must be provided (850) ** You wired the Down Direction and Final Limit switches. Now the car only runs up. What is the problem? - You wired the Down Direction Limit wrong. ** What are the effects of one rope sitting deeper in the sheave groove? - The rope wears out and breaks faster (250) ** There is a noise coming from a freight door. The sheave is moving but the chain is not. What is the problem? - Oil on on the chain ** What is the effect when you change a sling angle from 60* to 30* when hoisting and rigging? - More tension, less capacity. ** How many points of contact must be maintained on a ladder? - 3 points at all time.
- What is the conversion formula when measuring Inch to MM? - 25.4 Inch to MM (.03937) 2.54 Inch to CM (.3937) ** You open a Dumbwaiter access panel and it still runs. What is the cause? - Pit Access switch is not working. (550) ** You perform a static load test with the pit valve in the closed position. The car sinks 6" in 15 minutes. What is the cause? - Cylinder leak (520) ** Where should you point the fire extinguisher when putting out a fire? - At the base of the fire
** 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 bypassed till the car is moving in the up direction. ** During construction, you land an escalator but it is 10mm to low. What is wrong? - Pit is too deep or Column Mark is off. (825) ** During construction, the Omega CWT rails have been damaged. Why? - Overtightened from rail bracket. (215) ** How do you attach brackets to brick/concrete blocks? - "Inserts" 1/4" back from brick/concrete blocks ** Given a generator that runs at 600 rpm and has 4 Poles, what is the output frequency? - 600/60seconds = 10x2 = 20 HZ ** If an Exclusive OR gate was connected to a NOR gate and attached to a AND gate with a high out put, what must the input at the Exclusive OR gate A and B be? - Both must be high ** Using Binary logic, what DIP switches need to be in the " On" position of a 128 bit 30 second timer set for 150%? - 1,3,4,6 = 45 ** How must a 9 lead 480/240 motor be wired for low voltage setting? - L1 (1,7). L2 (2,8). L3 (3,9). (4,5,6) ** What does a square with a darkened upper triangle represent? - DC Relay Square with lower triangle = Latching Square with an Arrow through it = Timer ** 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. ** You get a trouble call for In-Op freight door. What must you do first before you begin work? - Block the door open.
** You have to run an EMT run with 3 - 90s, 2 - 45s and a Saddle bend. What will be required? - An Intermediate Pull Box. No more than 360 degrees.
- What is the Max distance between Raceway supports? - 15'
- What is the Max distance from Strain Bars? - 100' ** What is the ratio between diameter and Loop of a Traveler? - 30 times. ** What is the minimum amount of Spares that should be pulled? - 10% ** At what speed should the Governor Switch contact be set to open? - 90 - 95% of Governor tripping speed.
- What is the Max clearance between Door and Sill? - 3/8". (1/4" - 3/8") ** What is the minimum Gib to Sill? - 1/4"
- What is the minimum gap Sill - Sill? - 1/2" ** What is the Max gap Sill - Sill? - 1 1/2"
- A Force of 5000 lbs is applied to a plunger with an area of 25 sq inches. What is the system pressure? - 200 psi. (5000 lbs/ 25 sq inches = 200 psi ** How many gallons are needed to run a 4" plunger 25'? - 16.3 gallons (V = A(H)
- In Bi-Parting doors, what gap is allowed before Gate switch is opened? - 3/4" Max
** What do you do before running a Hydro elevator after the car is built? - Check piston for debris and make sure Head is tight.
- What is going on if you add power to a generator but motor doesn't gain more speed? - Generator is Saturated.
- What is Relief set at? - 150% ** What is the Maximum door closing force? - 30 lbs (7 lb Kinetic Force) ** What do you do before replacing a relay on a controller? - Turn power off and Lock our Tag out
- When are Oil Buffers required? - Above 200FPM
- What amount of Crosby's do you use on 1/2" rope? - 3
- SCRs are good for what? - They are quieter and cause less vibration than an MG Set. ** If rigging a motor into the Overhead, what type of rigging to prevent it from spinning? - Hoisting Jack
- If changes need to be made during construction, who do you inform? - Mechanic In Charge ** If you get a complaint that all floors make noise, what should you check first? - Car doors ** What must a Pit have? - Stop Switch and Pit Light. *If a Handrail Switch is tripped and you reset it but the escalator immediately turns back on, what is the problem? - The Start Switch is stuck in an "On" position.
** What is a Selective Collective control system? - A controller that allows an Elevator to Bypass calls in the opposite direction of travel. ** What is the smallest wire permitted in an Elevator install? - # 24 gauge.
- In what section of the NEC is Elevator, Escalator, Dumbwaiter and Moving Walks found? - 620
- What is the Max length Motor- Generator leads can be to the controller without a raceway? - 6'
- What is the smallest wire allowed in a Traveling cable? - # 20 Gauge
- What are the most common features of Load Weigh? - To control the Generator field and express operation.
- What is required on the Cartop by ASME? - Inspection Station, Light, Duplex receptacle. ** If the DC output of a 3 phase rectifier is lower than specified, what is the problem? - One Input phase is missing.
- What is the Overlap minimum on 2 and 3 speed doors? - 5/8" ** What is the Max gap of the Leading Edges of Center opening doors? - 1/2"
- 1 gallon is how many cubic inches? - 231 ** What best describes the operation of a typical Hydro Block Valve with an Elevator parked at the lobby? - The Down Valve is closed. The Check Valve is closed. The Up Valve is open. *What is the definition of Working Pressure? - Full Load Up pressure
- What is the conversion from Kilograms to Lbs? - 1 Kilogram = 2.2 lbs Ohms Law - Circuit Symbol - Type of Gate - Logic Characteristics - Rules for Series Circuits - Rules for Parallel Circuits - AC Sine wave Frequency and Period - AC Sine Wave "Effective Value" - AC Sine Wave "Average Value" - AC Sine Wave "Peak Voltages and Currents" - Mechanical and Electrical Degrees - Ohms Law for AC "Phasing" -
- When are comp ropes (instead of comp chains) required? - 700 FPM ** What diameter cable can be used as a handrail? - 1/4" steel cable 3 phase rectifier Output? - 1.33 x Input
Refer to figure 22. If the brake contact E fails to open when the brake coil is energized, what will happen?
- The brake coil current will be unchanged Refer to figure 28. You observe that the brake time has shortened, preventing the car from leveling properly. Which of the following would cause this condition? - Diode open ** You need to replace a 3 phase , 60 cycle AC motor which is missing the data plate that once showed the RPMs. If you know the old motor had 6 poles, what is the approximate RPMs the replacement motor will be rated for? - 1200 ** If a rectifier with a 220 VAC input blows its 200 microfarad 300 VDC filter capacitor, what is the problem? - Intermittent high output current ** What do you use to keep a machine from moving side to side? - Kick Angle
- What do you hold a machine beam down with? - Tie downs
- What is the strongest type of rope? - Seale rope You are using a 4K capacity hoist reeves 4:1 what is the Max you can lift? - 16k ** What is the boom out signal? - Arms out, thumbs out
- If there is high screeching, what should you check? - SCR drive motor bushing ** You get to a job where there is low voltage to a motor after a MOD, during which the mainline disconnect was moved 30' away. What is the fix? - Increase wire size ** If a traveler is 1.25" in diameter, what is acceptable for a loop? - 1.25 x 30 = 37.5 (30 x diameter)
** Call cannot go to 2nd floor without 3rd floor call but won't go down from 3rd without 2nd floor call, what's the problem? - 2 F1 4/ ** 2nd floor PI turns on then quickly extinguishes, why? - X1 4/
- What's the Max over speed on a Moving Walk? - 20%
- Where is the Tension Sheave in a Moving Walk? - Tail end Freight Loading Classes - ** Transformer Efficiency? - Power out divided by power in (If a transformer rated at 500 watts is 96% efficient, the primary requires 520 watts at maximum output loading) ** 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 ** Car is running normally but the buzzer will not shut off. Why? - EHP 3/2 shorted. (Fire Service) ** Relay STR has voltage, TRU has voltage, RU has no voltage. Why? - TRU 9/8 (Wye, Delta, Transfer) ** Why won't the motor start? - MOL 1 T/B (Motor Leads) ** What must first be installed on a false car? - Spring loaded safeties ** A Hydro top call is placed and call returns to the bottom floor without making it up. What's wrong? - Low oil timer
