As a branch circuit protection device, UL 489 circuit breakers are
tasked with protection of the circuit wiring
. Their purpose is to help prevent electric shock and fire, and to provide a means for electrical isolation during maintenance periods.
What provides branch circuit protection and where is it located?
The molded case circuit breakers
provide branch or feeder circuit protection against overload or short circuits using thermal-magnetic trip units to sense both temperature and current to operate the breaker.
What is a branch circuit?
:
the part of an electric wiring system that extends from any set of outlets as far back as the fuse box
, supplying and protecting them.
What is the purpose of a branch circuit?
General purpose branch circuits are 120 volts circuits
used for supplying lighting fixtures and receptacle outlets for most small portable appliances
. There are usually a number of general purpose branch circuits supplying lights and outlets in different rooms around a residence or commercial or industrial building.
What is meant by circuit protection?
What is circuit protection? Circuit protection is
the intentional installation of a “weak link” in an electrical circuit
. This is a fuse or circuit breaker, referred to here as a circuit protection device or CPD.
What are the types of branch circuit?
There are several different types of branch circuits in your home.
Dedicated appliance circuits. Lighting circuits. Outlet circuits
.
How many outlets can be on a branch circuit?
Technically, you can have as many outlets on a 15 amp circuit breaker as you want. However, a good rule of thumb is 1 outlet per 1.5 amps, up to 80% of the capacity of the circuit breaker. Therefore, we would suggest a maximum of
8 outlets for a 15 amp circuit
.
Why do we protect branch circuits?
As a branch circuit protection device, UL 489 circuit breakers are tasked with protection of the circuit wiring. Their purpose is
to help prevent electric shock and fire
, and to provide a means for electrical isolation during maintenance periods.
What is a branch circuit overcurrent device?
The definition of a branch circuit overcurrent device is outlined in Art. 100 as follows: “A branch circuit overcurrent device is a
device capable of providing protection for service, feeder, and branch circuits and equipment over the full range of overcurrents between its rated current and its interrupting rating
.
Do all motors need overload protection?
EVERY motor needs overload protection
of some type. Some small motors are impedance protected by design. Some motors can be overload protected by breakers or fuses.
What does a branch circuit consist of?
A branch circuit consists of
the conductors between the final overcurrent protection device and the outlet(s)
.
What is the rule of a branch circuit?
The basic rule:
The ampacity of branch-circuit conductors must not be less than the load to be served
.
What is an individual branch circuit?
Installed
in permanent locations
such as an electric range, a clothes dryer, or an air conditioner. These circuits usually lead directly from the distribution panel to the appliance and do not serve any other electrical devices. These circuits can be any amperage size.
What are 3 types of circuit protectors?
There are two general categories of circuit protection: 1) Fuses 2) Electro-mechanical circuit breakers. Each has its advantages which will be discussed here. Fuses break down into three convenient categories —
fast-blow, slow- blow, and semiconductor
.
What is an example of a circuit protection device?
Examples of overcurrent protection devices are many:
fuses, electromechanical circuit breakers
, and solid state power switches. They are utilized in every conceivable electrical system where there is the possibility of overcurrent damage.
How does a protection circuit work?
The circuit
monitors the voltage of a Li-Ion battery and disconnects the load to protect the battery from deep discharge when the battery voltage drops below the lockout threshold
. … In a discharged condition, current to the protection circuitry continuously discharges the battery.
