Quiz 3 - Commercial Wiring - Unit 2

Question 1

Figure 2-3 is indicating

Answer 1

26-240(2) - the enclosure must be locked

12-012 - rules for underground conductors in conduit

6-300(3) - an underground entrance to a building must be sealed

All of the above

Question 2

Figure 2-4 is indicating,

Answer 2

A busway (bus duct) is connecting the utility transformer to the main switch

A busway (bus duct) is connecting the utility transformer to the secondary switches

A busway (bus duct) is connected underground

Question 3

Transformers use liquids (oil/synthetic) to reduce heat at the core of the transformer.

Answer 3

True
False

Question 4

Oils containing PCB’s require a safe steps for disposal.

Answer 4

True
False

Question 5

Dry-type transformers are cooled by open air flow and/or fans.

Answer 5

True
False

Question 6

Figure 2-6 is indicating a basic transformer connection between the high voltage primary and the distribution.

Answer 6

True
False

Question 7

Figure 2-9 is indicating,

Answer 7

A system that is grounded at the first point of distribution (secondary)

A 3 phase primary 600V to secondary 208/120V transformer connection

Primary feed is Delta configured and the Secondary is Wye configured

All of the above

Question 8

Figure 2-11 is indicating

Answer 8

A neutral is achieved by grounding the coil of a transformer

The neutral is grounded on the secondary

The neutral is grounded on the primary

Both A and B

Question 9

Figure 2-12 is indicating

Answer 9

The primary side is expressed as H1, H2

The secondary side is expressed as X1, X2

The primary and secondary are both Delta configurations

All of the above

Question 10

The most commonly used system for modern commercial buildings is the 3 phase, 4-wire wye system.

Answer 10

True
False

Question 11

Figure 2-14 is indicating,

Answer 11

Potential and Current transformers are connected around the high-voltage section of a substation

Watt-hour and Varhour meters are monitoring a delta configured autotransformer

The high voltage line feed is 4160V

All of the above

Question 12

Figure 2-16 is indicating,

Answer 12

A 1,200A 3 phase main

All sections of the switchboard must be bonded together

Bonding must be in accordance with 10-616

A #6 AWG is connected to the water main

Three 4” conduits containing 750MCM conductors are feeding the service

All of the above

Question 13

Table 2-3 is showing an underground configuration for conductors in raceways according to T-D11.

Answer 13

True
False

Question 14

Figure 2-16 and 2-17 are two images of the same service equipment.

Answer 14

True
False

Question 15

Grounding isn’t used for saving lives and protecting equipment.

Answer 15

True
False

Question 16

Grounding helps to,

Answer 16

Minimize voltage spikes

Stabilize voltage to ground

Provide a low impedance path to ground

All of the above

Question 17

Ground-fault damage is determined by the overcurrent device response time and the amount of fault current.

Answer 17

True
False

Question 18

Figure 2-20 is indicating,

Answer 18

The metal water pipe is used as a grounding electrode

The gas pipe and hot water pipe are bonded to ground

Service neutral is considered a grounded conductor

A bond bushing is connected to the service raceway

A bonding jumper is installed around the water meter

All of the above

Question 19

Figure 2-21 is showing how all parts being bonded together is known as ‘system grounding’

Answer 19

Question 19 options:
True
False

Question 20

Equipotentiality means conductive parts are at a substantially equal electric potential

Answer 20

True
False

Question 21

Exposed, non current carrying parts of a system must be bonded together according to section 10.

Answer 21

True
False

Question 22

Conductors used for grounding must be either protected or resistant to corrosive conditions.

Answer 22

True
False

Question 23

Figure 2-22 is indicating,

Answer 23

A concrete-encased electrode

A rod electrode

A plate electrode

All of the above

Question 24

Figure 2-23 is a ground bushing used at the end of raceways at a point of connection. This bushing requires a ground connected under the attached lug.

Answer 24

True
False

Question 25

Grounding the secondary side of a wye connected transformer will establish a new service.

Answer 25

True
False

Question 26

Figure 2-31 is indicating two different types of ground bushing interconnection. One is looped using one conductor between conduits, the other has separate bonding conductors for each conduit.

Answer 26

True
False

Question 27

Ground fault protection is provided on the line side of the service disconnecting means.

Answer 27

Question 27 options:
True
False

Question 28

Ground Fault Protection circuit devices,

Answer 28

Were developed to detect high voltage fault currents

Were developed to detect low value phase to ground arcing

Were developed to detect low value ground to bond arcing

Question 29

An arc fault that generates 600 amps may still be allowed to flow through (not trip) an overcurrent device rated for 1600 amps.

Answer 29

True
False

Question 30

GFP monitors sense phase to phase faults.

Answer 30

True
False

Question 31

GFP’s and GFCI’s are the same.

Answer 31

True
False

Question 32

The electrician can minimize the possibility of an arc by,

Answer 32

Ensuring conduit couplings and fittings are installed properly

Ensure conductor insulation isn’t damaged

Installing insulating bushings on all raceways

Properly grounding and bonding the electrical system

Ensuring all electrical connections are tight.

All of the above

Question 33

The electrician shouldn’t work on live panels because they could end up being the path to ground for a fault current.

Answer 33

True
False