IDEAL SureTest 61-164 Instruction Manual page 2

Arc Fault Circuit Interrupters
There are two main causes of fires to installed wiring within the electrical distribution
system. The first is arcing within the circuit. An arc fault is characterized by an erratic
flow of electricity. Because normal breakers were designed to protect against short
circuits, arc faults occurring in damaged cable can continue undetected. These leads to
hazardous situations such as high temperatures that could ignite nearby combustible
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materials
To offer protection against these conditions, the 2002 edition of he National Electrical
Code (NEC), requires the installation of Arc Fault Circuit Interrupters (AFCI) in bedroom
circuits in new residential circuits.
guidelines are Arc Fault breakers. These breakers, which are manufactured by a
number of companies, have a special circuit within the breaker to detect arc fault
conditions on the branch circuit.
These devices should be tested upon installation to ensure that the breaker will
adequately protect the circuit. An independent arc fault tester simulates an arc fault
condition on the line to determine if the breaker will protect the circuit.
High resistance connections
The second major cause of residential fires is a high resistance point in the circuit, such
as a loose connection, poor splice or defective electrical device. Current flowing through
these high resistance points causes heat to build up behind the wall. This can create a
smoldering fire if there are combustible materials nearby, and no way to dissipate the
heat.
Identifying potential problems
Most fixed wiring and receptacle hazards are hidden from inspection. A visual
inspection in the rough-in stage of residential construction may identify obvious
problems, such as a staple cutting through the conductors, but they may not identify a
loose wiring connection or a bad splice.
Normal instrument testing of a static circuit reveals little about the quality of wiring or the
integrity of the circuit. However, testing under load and calculating the voltage drop can
identify 90% of these hidden defects.
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IEC Fact Sheet, Arc-Fault Circuit Protection, Illinois Electric Council, Fact Sheet #28
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NEC code Articles {210.12 (A)}
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Currently, the only devices that meet the new NEEC
Loose wire connections create a high
resistance point within the electrical
system, which can lead to a breakdown
in insulation or even a fire.