Book #8 Flashcards
Solid state devices:
Can be provided with an integral disconnect
When can a final inspection by the inspection department be done on the electrical installation in a single dwelling?
After the electrical installation has been completed
What is the top layer involved with a thermit weld?
Magnesium filings
To whom do you report an unsafe condition on a construction site?
Your supervisor
Which operation will a punch down tool perform?
cut and terminate
Which undesirable condition may result from encircling metal-covered single conductor cables with support made of ferrous materials?
Reduce conductor capacity
What would be used to check an element for an open condition in an energized electric hot water furnace?
Clamp-on ammeter
What are the two precents to remember when doing open delta calculations?
57.7% and 86.6%
A fuse has the following stamped on the body of the fuse, “2000a 600v HRCI-MISC, 20 kaic. what does the 20 kaic stand for?
Kilo-amps of interrupting capacity
What is required for personnel to work in an area where chemicals are in use?
WHMIS qualification and availability of MSDS information
When should rough-in wiring on any new single dwelling installation commerce?
After the walls and roof are installed
What type of drawing would show all the major components of a building’s electrical system
Single line
When connecting a residential extra-low voltage thermostat, what does the R terminal designate?
Transformer
Which type of split-phase motor would most efficiently drive an air compressor?
Capacitor starting
Which DC motor has the highest starting torque?
Series
An Ac induction motor is required to have dynamic braking, how would this be done?
Applying DC to the stator
Copper welding by the thermit process is permitted to be performed in:
Dry locations
What is the primary purpose of skirting on a high voltage semi-con stress cone?
Minimize corona build up
What is the function of a triac lamp dimmer
It varies the voltage cycle across each lamp
What do you require to operate a powder actuated tool?
Certificate
When installing a PLC system, how do you test your inputs and outputs?
Energize inputs and outputs one by one
When C phase on a ground fault indicating system is shorted to ground, how will the ground detection device lights indicate the presence of a ground fault?
Two bright, one dark
What is prevented by installing a heat shrink material over high voltage underground splice?
Moisture penetration
What is the most important consideration when disconnecting a meter from an energized current transformer?
CT secondary must be short-circuited
Why is high voltage cable shielded
To prevent corona build-up
A circuit is thought to have a problem with harmonic distortion. which test instrument should be used to confirm the problem?
A digital ammeter and a digital voltmeter
What would cause a Class A ground fault circuit breaker to trip and disconnect supply to a circuit?
Overload, short circuit, and ground fault
When doing welds for a ground grid, what is placed at the top of the thermit weld mould?
Ignition powder
What happens to a squirrel cage motors slip and torque as a load is added?
Torque goes up, slip goes up
A DC motor obtains its supply from a half wave rectifier and a solid-state starter. if one diode of the rectifier opens, what will happen to the motor?
The motor would stop
If an analog DC voltmeter deflects in the wrong direction, the probable cause is:
Reversed polarity
How are sheath currents prevented on a 26.6kv high voltage cable?
drain one end and isolate the other
What is the term for the voltage produced in a photocell, module or an array of solar cells?
Photovoltaic
What is the function of the condenser in an air-conditioning unit?
Transfer heat to the outside
What is the function of the Furnace in an air-conditioning unit?
Transfer heat to the inside
What pumps refrigerant through the system on an air-conditioning unit?
Compressor
What transfers cold to the inside of an air-conditioning unit?
Evaporator
An apprentice wants more complex work, what shall you do?
Work with the apprentice, to assist you with more complex work
What shall be included in the job specifications?
Completion date
What should be used to clean DC machine Brushes?
Sandpaper
