Specification
Series
Screw terminal where a wire is connected to a
receptacle may become loose as it is pushed back into
the work box
Combination AFCI
“Combination” does NOT mean an AFCI + GFCI
Provides protection against the high-energy
parallel (line-to-neutral and line-to-ground)
arcing and low-energy series arcing.
햳
Combination = parallel + series arcing
Protects downstream branch circuit wiring, cord
sets, and power supply cords.
햳 Branch/Feeder AFCI only protects against
high energy arcing
Parallel
Arc
75A
≥
Series
Arc
5A
≥
Line to
Ground
Branch/ Feeder AFCI Combination Type AFCI
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120 V
60 Hz
120 V
60 Hz
120 V
60 Hz
The Branch/Feeder AFCI can only detect line-to-neutral and
line-to-ground arcing faults, as illustrated above.
A Combination Type AFCI detects all three types of arcing: line-to-neutral, line-to-
ground, and series arcing. The Combination Type AFCI differs from the Branch/
Feeder AFCI in its ability to detect series arcing faults.
120 V
60 Hz
120 V
60 Hz
Parallel
Arc
75A
≥
Line to
Ground
Branch/Feeder AFCI
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What is an arc-fault?
An arc-fault is an unintentional discharge of
electricity in a circuit.
Arcing exists in two basic varieties:
Natural, or normal occurring arcing:
- Occurs when a light is switched on or a
vacuum cleaner or any motor driven appliance
is turned on.
Unsafe arc-faults:
- Occurs either as series or parallel faults in wire,
electrical devices, or connected loads.
Arcing faults, which can and generally do go undetected
by traditional circuit protection means, can reach
extraordinarily high temperatures – upwards of 9,000
degrees Fahrenheit.
The heating of surrounding materials creates a carbon
remnant that acts as a high impedance conductor. As the
carbon path extends, the by-products of the arc increase
the available fuel source, magnifying the likelihood of a
fi re.
What causes an arc-fault?
Arc-faults may occur anywhere in the home’s
electrical system in several ways:
Line-to-Neutral
Damaged power supply cord (Example: door continually
“pinches” cord)
Pushing furniture against cords plugged into outlets
Line-to-Ground
Accidentally piercing electrical cable behind drywalls with
drill bit, nail, or screw
Hammering electrical cable staples too tightly into studs
during rough wiring