Indicate the minimum cable size recommended for a 50A breaker installed on a 115/230V system. 

Assumptions:

• Cable Type - Single-core 70 deg C thermoplastic insulated cables, non-armoured, with or without sheath
• Installation is enclosed in conduit on a wall or in trunking etc.

TTS 171: Part 1 Clause 9.12.1 states that "In residential buildings receptacle outlets shall be installed in each room, except bathrooms, such that no point, measured horizontally along the floor line of any wall, is more than 1.8 metres (6 ft) from a receptacle outlet."

For a room of length of 14 feet and width 13 feet, with a 3 ft doorway, determine the minimum number of receptacle outlets required? 

The illustration below shows the circuit connections for a 230V 50A receptacle. If the live and neutral conductors are 10 mm squared, what is the size of the ground conductor?

A contractor wishes to implement a fixed cable, electric power and lighting installation for the wiring inside a house. Select an appropriate cable specification number from the options below. You may consult Table D.1B below, for further information on the specification numbers.

An electric range has the following specifications

• Voltage: 230V
• Current: 40 A
• Power: 13.6 kW

In addition, the electrical installation will have the following features

1. 50A DP circuit breaker
2. Cable type: Single-core 70 deg C thermoplastic insulated cables, non-armoured, with or without sheath
3. Cable Size: 10 mm squared
4. Cable Installation method: Enclosed in conduit on a wall  or trunking etc.
5. Length of cable run: 59 feet

A 6000 BTU air conditioning unit has the following specifications

• Voltage: 115 V
• Current: 4.9 A
• Power: 540 W

In addition, the electrical installation will have the following features

1. NEMA 5-15R receptacle and 15A SP circuit breaker
2. Cable type: Single-core 70 deg C thermoplastic insulated cables, non-armoured, with or without sheath
3. Cable Installation method: Enclosed in conduit on a wall  or trunking etc
4. Length of cable run: 23 feet

Considering the voltage drops, what is the minimum recommended cable size for this installation?

A contractor has purchased a SPDT switch for residential wiring. How many cable termination screws does this switch have?

Indicate the minimum cable size recommended for a 20A breaker installed on a 115/230V system. 

Assumptions:

• Cable Type - Single-core 70 deg C thermoplastic insulated cables, non-armoured, with or without sheath
• Installation is enclosed in conduit on a wall or in trunking etc.

Indicate the minimum cable size recommended for a 15A breaker installed on a 115/230V system. 

Assumptions:

• Cable Type - Single-core 70 deg C thermoplastic insulated cables, non-armoured, with or without sheath
• Installation is enclosed in conduit on a wall or in trunking etc.

A contractor has purchased a DPST switch for residential wiring. How many cable termination screws does this switch have?