Specification

QO
®
and QOB Miniature Circuit Breakers
Special Application Circuit Breakers
9
07/2008
© 1998–2008 Schneider Electric
All Rights Reserved
QO-GFI and QOB-GFI Qwik-Gard
®
Ground-Fault Circuit Interrupters
Qwik-Gard
®
Ground-Fault Circuit Interrupters offer a means of providing ground-fault protection for
people. Qwik-Gard “people protection” ground-fault circuit interrupters are built as Class A devices in
accordance with UL Standard 489 and CSA C22.2 #144 for ground-fault circuit interrupters (GFCIs).
Class A devices must trip at 6 milliamperes of ground-fault current and above, and hold below 4
milliamperes of ground-fault current.
Qwik-Gard GFCIs provide the same branch circuit protection as standard QO circuit breakers. They
are longer than standard QO circuit breakers, and thus require more gutter space. All QO electrical
accessories except shunt trip and all QO mechanical accessories are available for QO-GFI and QOB-
GFI circuit breakers.
Qwik-Gard circuit breakers are UL Listed and CSA Certified and available in both one- and two-pole
constructions.
Qwik-Gard Ground-Fault Circuit Interrupter Operation
The ground-fault sensor in a Qwik-Gard GFCI continuously monitors the current flow in the load and
neutral conductors. The sensor compares the current flow in all directions. If the current flowing back to
the source is less than the current flowing out to the load, a ground fault exists. When the difference in
current flow exceeds 6 milliamperes, the sensor sends a signal to trip the GFCI. The trip will be
indicated by the Visi-Trip
®
indicator and the operating handle will move to the center tripped position.
Qwik-Gard Class A GFCIs include a self-contained means of testing the ground-fault circuitry. If the
GFCI is connected correctly, with the pigtail connected to the neutral assembly in the load center or
panelboard, pressing the test button will trip the GFCI and show a trip indication. UL requires that
GFCIs must be operational at 85% of the rated voltage.
07303093
07303092
2P QO-GFI
Circuit Breaker
1P QO-GFI
Circuit Breaker
B
Line
N
Ground
Trip
Solenoid
B
N
Load Terminals
Sensor
18,000 Ohm Resistor
Test
Button
B–"HOT" or Power Connection
N–Neutral Connection
Solid
State
Circuitry
07303101
Line
A
B
N
Sensor
Test
Button
Solid
State
Circuitry
Ground
Trip
Solenoid
Ground
Trip
Solenoid
18,808 Ohm
Resistor
Load
Terminals
A and B–"HOT" or Power Connection
N–Neutral Connection
A
B
N
07303101
One-Pole Qwik-Gard Circuit Breaker
Two-Pole Qwik-Gard Circuit Breaker