Study
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- A contractor wants to raise the car speed from 100fpm to 125fpm, it currently has a 12” sheave. What sheave is required?
100fpm / 125fpm = 12” / X
= 15”
- A MOV (Metal Oxide Varistor) burns out. You replace it, but cannot read voltage or resistance. What should you do?
Replace it with alarger MOV 630
- On a Ward-Leonard circuit the break is set, but the motor is trying to slip through the break. What is the issue?
SuicideCircuit 425
- You have an old DC motor and are adding an SCR drive, what do you do to the interpoles?
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.
- A hydro runs up with no load, but will not run with a full load. What is the issue?
The relief valve is settoo low 815
- 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?
22” 235
- 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?
Door Operator Disconnect/ MainLineDisconnect 535
- The contractor requests that the vertical center of a Rack and Pinion hoist be moved. How do you do this?
Adjust Tie Downs andWallTies 850
- Working pressure on a Hydro is 400psi. What is the maximum relief valve setting?
400psi x 150%= 600psi 815
- What must be installed on a false car before operation?
Spring Loaded Safeties 110
- There is slight arcing between the brush and commutator. What action must be taken?
None
Note: Heavy arcing=Lightbrushpressure, Heavy bush pressure=mechanical wear 430
- If rigging gear is roped 3:1 and a BEAM CLAMP is used to lift a 6,000lb load. What is the beam capacity?
18,000lbs.
Note:Beam capacity is cut in half with use of clamp, when rigging all blocks, rope, and clamps will be Equal to the lowest load rating210
13. How much resistance is measured over a normally closed switch?
1.2ohms. should be zero, but will never be that low
14. A car traveling in the hoistway always stops at the same spot and blows a fuse. What causes this?
Traveling cable has a cut/exposed wire ora short 515
15. How is a class 1 yearly buffer test preformed?
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.
Note: 5yr: Full loadFullspeed CWT: Fullspeed Empty 555
16. How many strain supports are required on a 350ft raceway?
4. 1every 100ft 505-510
17. How is stainless steel drilled out?
Slow speed and constant pressure 205
18. What is the required amount of retainer clips for wedge shackles and what is the spacing?
At least 2. First clip being 4 times the diameter of the rope from the top of the shackle, and the second clip is 8 times the diameter of the rope away from the shackle. 245
19. A 300ohm resistor burns out, but you don’t have another one. How can you make one?
2-600ohm resistors in parallel is 300ohms. Resistance is half of highest resistor in parallelcircuit. 3-225ohm resistors in parallelis 75ohms.345
20. When cutting laminated panels, which direction should the finish side face?
Finish side facing the cutting edge of the tool. Blade will burrthebackside255
21. How do you cut a finished floor?
Cutting blade away fromfinishedside255
22. A 480vac stepdown 240vac transformer is connected to a 3 phase rectifier, what is the output voltage?
320vac 3 phase full wave = 1.33xoutputvoltage. 715
23. A car is loaded with 125% and sinks, why?
Slipping through the break
24. If you find a broken or missing barricade what should you do?
Write up a formal inspection request
25. What are the consequences of misaligned joints on a Rack and Pinion?
Broken Gear teeth. CWT derailment. Excessive wear/ crease the surface ofthetube 850
26. A dumbwaiter is 9sqft in area, 4ft high, and capacity is 13.9lb/ft3. What is total capacity?
9 x 4 x 13.9= 500lbs Max capacity
27. You must enter a pit with a toxic atmosphere, how do you proceed?
Following proper OSHA procedure with proper trainingand PPE133
28. When changing a 1:1 car rated at 600fpm and 2,000lb capacity to a 2:1, what are the new ratings?
300fpm4,000lbs capacity Half the speed, Double thecapacity
29. A vertical platform lift has a clearance of 1 inch. How much will it have to move to meet code?
Move in ¼ inch. Code is ¾ inch
30. 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?
2500(car) + 1000(40%) 3500. 5000-3500=1500lbs lifted bythemachine240
31. How must Oxygen and Acetylene tanks be stored?
Vertically, 12 feet apart, or on a cart with a ½ hour fire barrierbetween them 205
32. What is code for sill to sill distance?
Minimum ½ inch Maximum 1½inches525
33.When drilling a jack hole in sandy conditions what type of drill rig is required?
Rotary orAuger bit.
Note: Rotary=Soft Percussion=Rocky Combo=Solid810
34. A customer does not want an escape hatch on a residential elevator, under what condition is this legal?
Manual operation mustbeprovided840
35. Your helper wired the down direction and final limit switches, now the car will only travel up, what is the issue?
The down direction limit was wired incorrectly.
36. What are the effects of one rope sitting deeper in the sheave groove?
The rope wears out andbreaks faster 245
37. There is a noise coming from a freight door. The sheave is moving, but the chain is not. What is the problem?
Oil on thedrivechain535
38. What is the effect when you change a sling angle from 60 degrees to 30 degrees?
More tension, less capacity. Any angle 30 or lessisdangerous100s
39. How many points of a contact must be maintained on a ladder? How far above landing must it extend? What is proper Ratio? What steps don’t weuse?
3 points of contact. 3 foot above. 4:1. Top2steps132
40. What is the conversion formula when measuring inches to millimeters?
1” = 25.4mm
41. You open a dumbwaiter access panel and it still runs, what is the problem?
Pit access switch is not working properly. 550
42. You perform a static load test with the pit valve closed. The car sinks 6” in 15 minutes. What is the problem?
Cylinderleak 805 520
43. Where should you aim a fire extinguisher to put out a fire?
At the base ofthefire 100s
44. 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?
The call is bypassed until the car istravelingup. 740
45. During construction you land an escalator, but it is 10mm low, what is wrong?
The pit is too deep or column MARKisoff. 825
46. During construction the Omega CWT rails have been damaged, what happened?
The Omegas wereovertightened. 215
47. How do you handle a co-worker who shows up drunk?
Speak with MIC, Call BA,callsupervisor. 100s
48. How do you attach brackets to brick?
inserts set back a ¼ inch into the block. Code could call forthrough bolts 220
49. What is Selective Collective System?
Controller allows elevator to bypass calls in the opposite directionof travel 740
50. Generator runs at 600rpm and has 4 poles, what is the output frequency?
(RPM / 60sec) x (number ofpoles / 2)
=(600rpm / 60sec) x (4 / 2)
=20hz
51. 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?
Both mustbeHigh 645
52. Using BINARY logic, what DIP switches must be on for a 128 bit 30 second timer set at 150%
Note: 1 2 3 4 5 6 7 8 = on or off
Note: 1 2 4 8 16 32 64 128 = number of seconds
Note: 32 + 8 + 4 +1 = 45 seconds
1,3,4,6=45 seconds
53. 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
11 wires. You do not need the duplicates
54. How must a 9 lead 480/240 motor be wired for High Voltage?
L1 (1,7) L2 (2,8) L3 (3,9) (4,5,6)
55. There is voltage at the switch, but none at A, what is wrong?
Open at R2 or R1 635
THE FOLLOWING QUESTIONS (56-62) REQUIRE THE USE OF PRINT 730
56. What does a square with a darkened upper triangle represent?
DCRelay
Note: Square with darkened lowertriangle = LatchingRelay
Note: square with arrow through it = Timer relay 730
57. The close door limit switch is not working, you have power at points 35-8, no voltage at 1-S2 why?
Door limitswitch malfunction Sheet 1
58. Car is running normally, but the Fire Service buzzer will not shut off, Why?
EHP3-2 shortedSheet 2
59. Relay STR has voltage, TRU has voltage, RU no voltage, why?
TRU9/8 openSheet 3
60. 2nd floor PI lights then quickly shuts off, why?
X1 4-6Sheet 2
61. Car will not travel to 2 without a 3 call, and will not go down to 3 without a 2 call?
2F1 4-6Sheet 1
62. Using Sheet 3, why wont the motor start?
MOL1 T/BSheet 3
63. The step level switch on an escalator has been tripped, where do you check?
The Upper and Lower Truss assemblies, trips if step sags more than1/8 inch825
64. You get a trouble call for an inoperable freight door. What must you do before you begin work?
Block open the door.LOTO.Barricades 540
65. You get shocked when attempting to move a car with a temp run bug, what is the problem?
Ground wire nothooked up 810
66. A motor needs a sleeve bearing replaced, what type of bearing do you need?
Friction bearing AKASleevebearing. 420
67. With a 7-foot platform and an inside cab wall clearance of 6’8”, what is the thickness or take up of the cab walls?
2-inch-thick walls
68. You notice Roughing on the Govenor and Tail Sheave. What should you check?
RopeDiameter 250
69. Car doors are dragging in the sill, how high should the car doors be above the sill?
¼inch 525
70. What type of safeties are required on a 300fpm car?
Type Bwedgeclamp 240
71. What stopping devices are required on vertical platforms?
2 pan switches. 15lbs max pressure
72. What type of oil is required for sleeve bearings?
Single viscosity SAE 20
73. What is the maximum inclination for moving walks?
12degrees 830
74. How does a GFI work?
Detects an imbalance between Hot andNeutral Wires 205
75. Who is required to provide MSDS or SDS for a solvent you are using?
Your employer 100
76. How do emergency doors swing?
Outwards
77. You have an EMT run with 3-90s, 2-45s, and a saddle bend. What is required?
An Intermediate pull box. 360 degrees is most bends for acontinuouspipe 505
78. What is the maximum distance between vertical race way supports?
15feet505
79. What is the smallest wire used inside travelers and outside of travelers?
#20awg #24awg 505
80. What is the maximum distance between strain relief supports?
100feet 510
81. What is the maximum length Motor-Generator leads can be outside of a controller?
6feet 505
82. In what section of NEC is elevator, escalator, moving walks, and dumbwaiters?
Article620 505
83. What is the ratio between the loop and diameter of a round traveler?
30 times 515
84. What are the most common features of Load Weigh?
Control generator field and Insideexpressoperation 515
85. What is required by ASME on the car top?
Inspection station, Light, andDuplex outlet. 515
86. At what distance from closed does the gate switch operate?
2inches 515
87. What is the minimum number of spares that should be pulled?
10% 515
88. At what speed should the Gov. switch contact be set to open?
Electrical 90% of Tripping speed for 150fpm-500fpm. 95% for +500fpm
89. If the DC output of a 3 phase rectifier is lower than specified, what is the problem?
AC fuseis blown. 1 input phaseis missing. 715
90. What is the overlap minimum on 2 & 3 speed doors?
Horizontal½inch Vertical1inch 530
91. What are minimum and maximum clearance between sill and car doors?
¼inch Minimum 3/8-inchMaximum 530
92. What is maximum leading edges for center opening doors?
½inch 530
93. What is minimum sill to gib engagement?
¼inch 530
94. What is minimum and maximum sill to sill gap?
½ inch to 1½ inch 525
95. 1 gallon equals how many cubicfeet?
231 815
96. How many gallons are needed to run a 6” plunger 30’?
Area = 3.14 x R2 = 3.14 x 6” = 18.84
Height = (12” x 30’) = 360”
Volume = Area x Height = 18.84 x 360” = 6,782.4
Gallons = 6782.4 / 231 = 29.36 gallons 815
97. A force of 5,000lbs is applied to a plunger with an area of 25 sq in. What is system pressure?
Pressure = Force / Area
Area= Force / pressure
5000lbs / 25 sq in = 200psi 815
98. Whatbestdescribestheoperationofa typical hydro block valvewiththeelevator parked atthelobby?
Downvalve:Closed Checkvalve:Closed Up valve: Open 815
99. What is the definition of working pressure?
Fully loaded to capacity, Full speedrunning up 815
100. What is the conversion for kg to pounds?
1kg=2.205lbs
101. On a geared machine the worm and worm gear are made out of what materials?
Steel and Bronze
102. What is the purpose of a gear reduction unit on a geared machine?
Increased lifting capacity
103. What holds a stopped Hydraulic elevator?
Check valve
104. What must be done if you get on top of a dumbwaiter?
Never fully get on top. Work only partially on with the mainlinedisconnect off 545
105. How do you measure an escalator hand rail?
Mark the top and bottom of the inclination, measure in between and move the car until the bottom mark isat the top, measure again and continue doing this until you see your 1 mark. The last measurement will be shorter. Add all the measurements together to getyourlength. 835
106. A moving walk has an inclination of 10degrees, what is the highest angle it can be?
12degrees escalator31degrees 830
107. In a Ward-Leonard system, if all 3 contacts close what will happen?
The car will run atfull speed. 415
108. What type of oil do you put in a machine?
Gear oil, non-detergent, single viscosity
109. A 75ohm resistor has blown, no replacement, how do you fix it?
3-225ohm resistorsin parallel. 3-25ohm resistors inseries
110. If a Rack and Pinion hoist is not plumb, level and square. What can happen?
SettheSafeties 850
111. What are extension tubes used for?
Necessary clearance for placement ofconcreteforms. 850
112. If a hoist motor is making noise, what is the problem?
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 onnotcheffect. 625
113. What is the area of a 10” plunger?
Area = Pie x RadiusSquared = 3.14 x 5 x 5 = 78.5 815
114. The escape hatch opens in what direction?
From the outside of the car up, preventing people from getting on top of the car
115. What drawing will show how many and location of fixtures?
Theelevator Abstract. Rails, lanterns, push buttons, etc. and quantity, color,material, etc. 175
116. 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?
12 x 3 = 36total floors
3 floors withno P.I. = 9
36 – 9 = 27 P.I. needed
117. If an elevator travels 1760rpm @ 60hz, how many hz needed to run at 600fpm?
20hz
600fpm / 60hz = 10
Note: assume 4poles 10 x 2 = 20 425
118. You see a saw tooth wave form when using an oscilloscope out of the encoder, is that good?
NO.
A perfect encoder shows a square wave. Saw tooth, when encoder hasfault. 350 630
119. What are the hand signals for crane operation?
Thumbsout = Boomout, Thumbsin = Boomin
Thumb up = Boomup, Thumb down = Boomdown
Finger upclockwise = Hoist up, Finger down counter clockwise = Hoist down
Arm out = Stop 128
120. 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?
Use a larger gauge of wire
121. What is the weight of 15 full 16’ rails and 2 – 8’ normal rails?
16 x 16’ x 15lbs= 3840lbs 220
122. What is an acceptable substitute for the top rail of a barricade?
¼ inch thick wire rope.
123. What is the proper way to test incoming voltage?
3 phase AC using digital meter: L1-L2, L1-L3, L2-L3
Hydro at pump starter. Traction at L1,L2,L3 715
124. When replacing a PCB in a controller what precautions must be taken?
Use a grounding wrist strap, and never remove anything with thepower on. 645
125. Who gives you a right to a safe work space?
OSHA 125
126. 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?
Underground. Annual static test required for unexposed cylinders. 800
127. What training must be done before you can enter a pit that has been classified as a confined space?
Confined spaceentranttraining. 133
128. Traction and Hydraulic machines have many hazards, what is most dangerous?
Rotating Equipment
129. You are installing a machine and sheave, where would machine and secondary sheaves be aligned?
In the center of theRail measurements. 230
130 You are testing an elevator with a rated speed of 500fpm. What is the minimum speed the safeties should set at?
Mechanical:115%x500=575 fpm
Electrical:90% x 575=517.5 fpm
131. What is one of the most dangerous Hazards in the trade and most obvious for us?
FALLS 105
132. You are installing machines, governors, and generators, and need to know the location where it needs installed. Where would you find the information?
The machine roomplan view 175
133. What is the minimum breaking strength of a wire rope used as Life Safety?
5,000 pounds
134. What is known as the silent killer?
CTW
135. You go to a trouble call and the building owner keeps asking when the car will be back up and if you can take any short cuts to get it up faster. What is your
response?
Give a reasonable response on time and safety factors. If that doesn’t work, he can FUCK OFF.
136. You are preparing to replace a resistor on an out of service car. What is the 1st thing do?
Make sure it is LOTO and verify no voltage.
137. What are 3 major factors in Hydraulic pit maintenance?
Oil, Tripping hazards, Electricity.
138. What is the tolerance for 3/8 at .003?
.372-.378 bilateral=2direction unilateral=1 direction
139. You are installing push buttons using snake eye screws. What type of screwdriver?
Tamper Proof 205
140. You are working with EYE BOLTS, where would you check for liftingcapacity?
NEVER use eye bolts for hoisting.
141. 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?
The mechanicaldetaildrawing. 175
142. 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?
Cup Screw
143. You have to measure the outside of a pipe. What tool would you use?
CaliperRule 205
144. You are installing spring buffers on a 200fpm car, what is the minimum buffer stroke?
200fpm = 4inch
Note: 100fpm = 1 ½ inch
Note:100fpm-150fpm = 2 ½ inch
145. You are going to replace the disc on your grinder, what test should you do before using?
Ringtest 130
146. How often do electrical cords need to be checked for continuity?
Every3 months 129
147. The DBG is 6’6” using 15lb rails with ¼ shim on the brackets, what is DBB?
(2) 15lb rails is 3 ½ deep = 7” total.
(2) ¼” shims = is ½”.
6’6” + 7 ½” =7 foot 1 ½inch
148. How does OSHA classify a competent person?
One who is capable of identifying existing and potential hazards, and who has authorization to take prompt, Correctivemeasurements. 125
149. Car weighs 7,000lbs with a capacity of 3,500lbs. what does the CWT weigh?
3,500lbs x 40%=1,400lbs
7,000lbs + 1,400lbs =
8,400lbs
150. You are stacking rails in a single hydro hoist way, with a rise of 48’ how many rails will you need?
48’ / 16’= 3 rail per side
3 x 2 sides = 6rails
151. Installing a 3,000lb capacity car, how much load will the break stop and hold?
125% ofratedcapacity = 3,000lbs x 125% =
3,750lbs 230
152. On traction elevators where are the bottom guide shoes mounted?
To thesafetyplank 240
153. 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?
6,000lbs 210
154. You need to find the DBG for the car, where would you find this information?
Final layout or Hoistway planviewdrawing 175
155. 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 iteasier?
Add another or more wraps to thecapstan hoist. 210
156. Responding to a call on a hydro, you determine that the 50amp circuit breaker that feeds the controller has tripped. What component of the elevator has the ability to cause this problem?
The pump motor
157. The motor field windings on a DC motor are wound around a laminated core. The composition of the core material is dependent upon which characteristics?
Permeability: ability of a substance to pack magnetic lines of flux in a space 415
158. You suspect a phasing issue with building power. Which controller device should you check 1st?
Reverse phase relay: detects incoming power loss of phase orphasereversal 820
159. How do you measure AC voltage on a Digital Multimeter?
Functionto VAC Red lead to Voltohm Black lead to common 405
160. Sometimes necessary to increase output of a DC generator to over speed an
elevator as part of the safety test. If maximum output is reached and speed cannot be increased, it is said to be what?
Saturated: cannot produce any more magnetic linesof flux 415
161. What hydro piece uses electrical power using the principle of electromagnetism?
Hydro Valve Solenoid: electro-mechanical device operated by a coil and having an iron core steel plunger asan armature. 815
162. Which of the following maintenance procedures addresses the issue of proper DC generator commutation?
Continued contact between brushesandcommutator 430
163. Customer is complaining that an older SCR drive powered elevator, is causing noise in the building power lines. What can help reduce the noise?
Isolation Transformer used to minimize electrical noise reflected to supply lines 410
164. In a series circuit with a 10K ohm resistor and a 2mA current, what is Voltage?
E = R x I =
E = 10,000ohm x .002A =
E = 20v
165. How would you connect an ohm-meter to check load resistance?
Blackto common Red toVohm Switch at Ohm. No power, take one lead off, connectin parallel, analog needs to be zeroed
166. How would you connect an ohm-meter to check load resistance?
Black to common, Red to V, ohm Switch at Ohm. No power, take one lead off, connect in parallel, Analog needs to be Zeroed1st 335
167. Exciter voltage comes from what source?
Generator 425
168. Your pulling (15) #14awg, (27) #16awg, (57) #18awg wires. How many spares needed?
(2) #14, (3) #16, (6) #18 = 10% spares required 515
169. You have (26) 16’ 22lb rails and (2) 8’ 22lb rails, what is the total weight of the rails?
27 rails x 16’ x 22lbs = 9504lbs
170. You need to replace an unmarked SINGLE PHASE transformer with primary voltage at 220vac current at 5amp. What size would you need to double it?
Note: kVa sizing must be calculated from primary or secondary volt + amp info.
Single phase kVa = (V x I) / 1,000
kVa = (220vac x 5amp) = 1100kVa
1100kVa / 1000 = 1.1 kVa
2.2 kVa needed to double
171. You have attempted to start up a 3 phase AC motor and stalls then hums or growls?
If the rotor bar becomes loose at the ring connection, or if the rotor bar cracks, current cannot flow through The bar and the entire rotor field is disrupted, causing loud growl or humming sound 435
172. Your fluke digital Multimeter reads 440vac, what value are you reading?
440vac RMS 615
173. You have determined that the period of an oscillation that you can feel in the car is .5 seconds. What is the frequency of the oscillation?
2hz Frequency from time or Period F=1/T F=1/.5=2hz 350
174. Customer complains that elevator is having door problem at every floor.
Where do you start trouble shooting?
The car doors 525
175. Freight doors are binding because they are hanging out of square, what adjustments can you make?
Adjust door track chains. 535
176. You are about to start installing your duct run in the hoist way. What is the best method to give you the straightest line?
Using a plumb bob, snap the line, and measure off of the rail. 510
177. When installing multiple Traveling cables, where is the 1st cable located?
1st is closest to the rail. 515
178. 2 controllers in a small machine room face each other, what is the minimum clearance between them?
36 inches 235
179. When installing travelers, what is the minimum length of vertical suspension at both ends before the loop starts?
4 feet 515
180. You attempt to adjust a new VV-VF door operator, but it operates in the wrong direction. How do you change the direction?
Change the phase sequence 530
181. You receive a call that a center opening car is running with one door partially open, how is this possible?
The gate switch is activated by door drive, but the relating device has failed. 530
182. In order to properly bond an isolation platform, where should you connect your bonding straps?
From the platform to the car sling. 515
183. As a mechanic you are sent to install an escalator, what point of reference would you use to square the unit?
Column LINE 825
184. Escalator demarcation lights are required by code for what reason?
Provides passengers a visual indication when entering and exiting the unit 185
185. While adjusting a passenger elevator door operator with a PERMANENT MAGNENT DC motor. Which operation would you perform to control the motor?
Speed and Torque control is accomplished by varying armature current and voltage
530
186. What does ASME code specify regarding clearance between skirt panel and the side of the step tread?
Skirt board switches required at upper and lower ends. Gap no more than 3/16” 825
187. After receiving an inspection report, one violation is door closing force. After checking you read 50lb of door force, is this code? How do you make it code compliant?
Not code. Code is <30lb. To fix you need to adjust the torque/speed of door operator. 530
188. You momentarily actuate the motor starting relay, the direction of rotation is not correct, what can be done to change rotation direction?
Reverse any 2 leads of incoming motor phases.
189. Before you can move a piston on a hydro, what precautions must be taken?
Check the piston for debris and tightness of the head, make sure pit is clear. 805
190. You are preparing to hoist the car for cable installation, before doing this, what needs to be installed?
The governor cable 520
191. While on service you observe the mechanical style safety edges on center opening doors bumping into each other, reopening the doors. Where do you need to look to repair this problem?
The safety edge retraction mechanism 530
192. You are about to trouble shoot an elevator that is off, what print would help to make it easier to trace the circuits?
Straight Line Diagram
193. The fuses on a 3 phase input to DC direct drive are open, and the elevator will not run, what needs to be done to check for a shorted SCR?
Remove the SCR, connect +lead to Anode, -lead to cathode, jumper between ANODE & GATE .7v if good. Remove jumper and it should stay on, remove a lead should read infinite 635
194. Trouble shooting a 3 input AND gate, all inputs are high, but the gate output is low. What is the problem?
Faulty gate. Truth table says output should be high. 645
195. Your going to a trouble call you find that the machine room has 2 inches of water in it, what is the first thing you do?
Leave the Machine room 115
196. You find a blown fuse in the DC circuit feeding the door motor. When picking a replacement fuse what should you do?
Compare the blown fuse to the fuse rating in the straight line diagram 530
197. A DC door motor supplied from a 3 phase rectifier runs slow. The DC voltage is normally 320 is 220. What should you do?
Check the fuse feeding the AC rectifier 530
198. There is a call that a traction elevator is stuck in the overhead. In order to get the car down, what circuits do you need to jump out?
The primary safety circuits 720
199. You just pulled multi-cables down the hoistway of a high rise. How should you provide strain relief for the cables?
Required every 100’. Begin at the lowest and work upwards to adjust tension 510
200. Installing Horizontal sliding doors with guides in each door panel, how far must each guide engage the sill gauge?
1⁄4 inch 525
201. Your supervisor informs you to change software on a hydro microprocessor board. The software is a 24 pin DIP package. To properly orientate the new chip on the board, what must you do?
Verify that the notch on the dip chip matches the notch on the board 625
202. You need to speed up an AC motor that has a fixed number of poles. How can you speed it up using the RPM formula?
Change the frequency. RPM= 60 x F / P/2
203. You have finished digging a hole hydro, the jack is not on site. What must the hole have on it before you leave?
A welded cover 805
204. A CWT frame weighs 10,000lbs and needs to be increased by 5%. What is the new weight of the frame?
10,000lbs x .05 = 500lbs +10,000 = 10,500lbs
205. You have 32’ of rise in scaffolding and are using a 3’x5’ base. Where are tie offs?
1st at 12’ and cannot be more than 26’ apart vertically 30’ apart horizontally
206. How is a step level switch on an escalator reset?
Manually
207. What is the Law of Power?
P = E x I
208. What is the maximum voltage drop that can occur across a 500watt resistor carrying 2amps of current?
E = P / I
E = 500watt / 2amps = 250volts
209. While testing for a locked rotor condition, what could happen if the testing was carried on for too long?
Damage to the stator or rotor
210. What is needed to coordinate the movement and to dispatch hall calls?
A group controller
211. Where is weight added on a freight door for balancing?
On the top.
212. What door is heavier on bi-parting freight doors?
The lower door because of the tucking sill
213. What happens to the break when contact E opens?
Inserts more break resistance in the circuit, reducing the value of the break current. More resistance to hold the coil up and release current draw.
214. In a circuit with capacitance of 5mf 120v and 200K ohm, how long to fully charge?
5TC .005 x 200 = 1(TC) 1 x 5 = 5 to fully charge.
Note:1 time constant = 63.2% 5 time constant = 99%
Shunt Overloads:
Parallel connection. Designed to conduct current around mechanical joint
Resistive element used in parallel with DC armature movement to bypass calibrated portion of current
LULA RESI DUMB WAITER
Rise: 25’ 50’
Speed 30fpm 40fpm
Capacity 1400lbs 940lbs 500lbs or 13.9lbft3
Area 18sqft 19sqft 9sqft
Valve Operations:
Check valve: oil flow in 1 direction
Up valve: controls up start and accel to high speed, up slow down, up level, up stop
Down valve: Elevator not running so it depends on system pressure
Bypass and Relief: bypass oil if striking obstruction. If relief pressure is too low it will not pick SCR:
DC door motor control and commonly in direct drives.
3 terminal device acts as on/off switch by pulsing the gate with positive voltage Once on SCR remains on until Anode & Cathode voltage equalizes, or Anode & Cathode are reverse biased, or until voltage is removed from Anode & Cathode
Amplifiers:
Inverting: Op amp(input) supplied to. NEGATIVE
Non inverting: Input. POSITIVE Inductance in a DC Break:
R1 controls rate the magnetic field builds, R1 controls time it takes the break to energize after the BR contact closes. R2 is the discharge path for the break coil. R2 controls the time it takes the break to set when BR opens. R2 controls voltage spikes from the collapsing magnetic lines of the break coil when discharging, thus reducing spikes from reaching other parts of the circuit.
