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ELEVATOR MECHANIC EXAM
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ELEVATOR MECHANIC EXAM ACTUAL LATEST UPDATED TEST
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ELEVATOR MECHANIC EXAM ACTUAL LATESTUPDATED TEST
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? - ANSWER The pump motor
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? -
ANSWER Permeability: the ability of a substance to pack in magnetic lines of flux
in a given space
You suspect a phasing issue with building power. Which controller device should
you check 1st? - ANSWER Reverse phase relay: detects if incoming power has a
loss of phase or phase reversal
How do you measure AC voltage on a Digital Multimeter? - ANSWER Function to
VAC Red lead to Volt ohm
Black lead to common
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? - ANSWER Saturated: cannot produce
any more magnetic lines of flux
,What hydro piece uses electrical power using the principle of electromagnetism? -
ANSWER Hydro Valve Solenoid: electro-mechanical device operated by a coil and
having an iron core steel plunger As an armature
Which of the following maintenance procedures addresses the issue of proper DC
generator commutation? - ANSWER Continued contact between brushes and
commutator
Customer is complaining that an older SCR drive powered elevator, is causing
noise in the building power lines. What can help reduce the noise? - ANSWER
Isolation Transformer: Used to minimize electrical noise from being reflected back
to supply lines
In a series circuit with a 10K ohm resistor and a 2mA current, what is Voltage? -
ANSWER 20v
E=R x I
10,000 x .002= 20v
How would you connect an ohm-meter to check load resistance? - ANSWER Black
to common Red to V ohm Switch at Ohm.
No power, take one lead off, connect in parallel Analog needs to be Zeroed 1 st
Exciter voltage comes from what source? - ANSWER Generator
Your pulling 15 #14awg 27 #16awg 57 #18awg wires. How many spares needed? -
ANSWER 2 #14
, 3 #16
6 #18
10% spares required
You have 26 16' 22lb rails and 2 8' 22lb rails, what is the total weight of the rails? -
ANSWER 27 x 16 x 22 = 9504lbs
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? - ANSWER
KVa sizing must be calculated from primary or secondary volt + amp info
Single phase kVa=(VxI) / 1,000 kVa=220x5== 1.1
kVa 2.2 kVa needed to double
You have attempted to start up a 3 phase AC motor and stalls then hums or
growls? - ANSWER 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
Your fluke digital Multimeter reads 440vac, what value are you reading? - ANSWER
440vac RMS
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? - ANSWER 2hz
Frequency from time or Period F=1/T F=1/.5= 2hz
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