Permissible Loads in a Branch Circuit
What is a branch circuit?
Any circuit ran off of a breaker or a fuse.
How much is 1 mL in inches
Which wire type is more conductive?
Copper
what are the usual solid wire sizes for residential wiring?
14, 12, and 10 AWG
What is it called when a circuit stops working?
A "short" circuit.
What is a 30 amp circuit used for?
dryers, stoves, water heaters, and other devices similar.
What does KCMIL mean?
Thousand mils
Which wire is more resistant?
Aluminum
what is ampacity
maximum amperes a conductor can carry without exceeding temperature rating
What are some of the dangers of having a loose connection in a circuit?
electric shocks or fires.
What can a 40-50 amp circuit be used for?
Cooking equipment fastened in place and HVAC equipment.
What does a branch circuit rating do?
Determines the minimum ampacity of branch circuit conductors.
How does temperature impact Aluminum wire?
It will expand or contract
What kind and size of wire is commonly used in a raceway
10 AWG stranded
What type of material should be used on a wire connector labeled with "AL"?
Aluminum.
What are 50+ amp circuits used for?
Supplying electric furnaces, large heat pumps, air conditioning, large double ovens, and similar equipment
What NEC rule permits the use of the next highest standard of the overcurrent device rating?
240.4 (B)
What is corrosion?
Contact between dissimilar wires with moisture present.
what is the ambient temperature the wire cant exceed
86 degrees F
What materials can be used with a wire connector labeled with "AL/CL"?
Copper and aluminum.
What percentage must utilization equipment not exceed on a branch circuit?
80%
If a 6 AWG conductor with type THWN insulation rated for conductor with 75 degree celcius has an allowable ampacity of what?
65 amperes
What is the conductivity of a 8 AWG type THHN copper wire compared to aluminum?
Copper: 55 amps
Aluminum:45 amps
when are wires generally solid
when used in armored cable
What could happen over time if copper and aluminum are joined together in a circuit.
Weaken the wire or joint by corrosion, causing the electrical current to weaken.