309A Wiring Methods and Materials

Question 1

What is the maximum fill ratio for a conduit containing three or more conductors according to the CEC?

Accepted Answer

40%

Answer

25%

Answer

31%

Answer

53%

Question 2

What type of cable is designated TECK90 used for in Canadian electrical installations?

Accepted Answer

Exposed industrial wiring in wet or dry locations

Answer

Underground residential distribution

Answer

Low-voltage communication circuits

Answer

Temporary construction wiring only

Question 3

What is the minimum bending radius for a 1-inch rigid metal conduit?

Accepted Answer

6 times the conduit diameter

Answer

4 times the conduit diameter

Answer

8 times the conduit diameter

Answer

10 times the conduit diameter

Question 4

Which conductor insulation type is rated for both wet and dry locations at 90°C?

Accepted Answer

RW90

Answer

TW75

Answer

T90

Answer

R90

Question 5

What is the purpose of a bonding bushing on a conduit entering an electrical panel?

Accepted Answer

To ensure electrical continuity across the connection

Answer

To reduce vibration

Answer

To prevent water ingress

Answer

To support the conduit weight

Question 6

According to the CEC, what is the minimum cover required for a junction box mounted flush with a non-combustible surface?

Accepted Answer

6 mm maximum gap

Answer

No gap permitted — must be flush

Answer

3 mm maximum gap

Answer

12 mm maximum gap