Question 31
Which type of three-phase motor starter uses a transformer to reduce voltage during the starting sequence?
Question 32
Which device allows a motor to be started with reduced voltage by connecting windings in Star then Delta?
Question 33
What does the term 'ampacity' refer to when selecting conductors?
Question 34
When reading a floor plan, what does a dashed line between a switch symbol and a light symbol usually represent?
Question 35
A luminaire is flickering intermittently. You have confirmed that the lamp is good and the supply voltage is steady. Which of the following is the MOST likely cause?
Question 36
When installing a control circuit for a motor starter, what is typically used to provide low-voltage control from a higher-voltage supply?
Question 37
You find that a 3-phase motor occasionally trips its overloads when starting under heavy load. Which is the BEST corrective action consistent with typical motor protection rules?
Question 38
According to safe work practices, when should an electrician use a fiberglass or non-conductive ladder?
Question 39
When reading an electrical floor plan, what does the legend or symbol list provide?
Question 40
A three-way switching arrangement is used in a stairwell. What is the main advantage of using three-way switches in this location?
Question 41
While troubleshooting a motor that will not start, you find the control fuses are good and the overload relay is not tripped. What is a logical next step?
Question 42
Before starting work on a branch circuit in a dwelling unit, what is the first step an apprentice electrician should take?
Question 43
Which of the following is the safest method to move a heavy dry-type transformer across a finished floor?
Question 44
You are asked to add a new 40 A, 240 V two-pole breaker to an existing 120/240 V, single-phase, 200 A residential panelboard in Canada. The panel is already close to capacity, and several existing breakers are double-lugged on terminals not listed for two conductors. What is the most appropriate action before adding the new breaker?
Question 45
An industrial control panel contains variable frequency drives (VFDs) feeding several motors. Nearby instrumentation circuits are experiencing interference and erratic readings. What is the most appropriate mitigation strategy?
Question 46
Before starting work on a circuit that has been locked out, what should the electrician do after applying the lock and tag?
Question 47
What is the typical colour used in Canada for the insulated conductor identified as the grounded (neutral) conductor in a 120/240 V single-phase system?
Question 48
When terminating a stranded copper conductor under a screw terminal, what is the best practice?
Question 49
A motor fails to start when the start pushbutton is pressed. The control circuit fuse is intact and line voltage is present at the line side of the contactor. Which is the next most logical check?
Question 50
A motor control centre (MCC) lineup is shown on a one-line diagram with feeder breakers and several motor starters. When planning lockout for one motor, what is a critical step?
Question 51
A large variable frequency drive (VFD) is installed on a 480/600 V system with long motor leads. What is a key concern for the motor and cable?
Question 52
Which statement best describes a branch circuit?
Question 53
When reading a single-line diagram of a small commercial service, what does a symbol showing a transformer between the utility and the main switchboard represent?
Question 54
On a control schematic, what does a normally closed (NC) contact symbol represent in terms of its state when the device coil is de-energized?
Question 55
A 3-phase motor is overheating and drawing unbalanced currents on each phase. Line-to-line voltages are balanced. What is the MOST likely cause?
Question 56
On a complex lighting control schematic using contactors and multiple switches, a luminaire bank does not energize even though the control switch indicator light is on. Line voltage is present at the control transformer primary. What is the MOST logical next diagnostic step?
Question 57
A variable frequency drive (VFD) is installed to control a 3-phase motor. The motor leads are extended through a long run in metallic conduit. Excessive electrical noise is being observed on nearby communication cables. What mitigation measure is MOST appropriate?
Question 58
Which colour is typically used for the identified (neutral) conductor in Canadian residential wiring?
Question 59
When the ohmmeter function of a multimeter is used, what must be done before measuring a circuit component?
Question 60
In an industrial MCC, a new variable frequency drive (VFD) is installed for a motor. Which wiring practice is most critical to minimize electrical noise and interference?