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    25 Products

    Square D Load-Center Circuit Breakers

    Match these circuit breakers to Square D breaker boxes or panel boards of the same manufacturer series. Because they are thermal-magnetic, these breakers trip two different ways. They either trip when heat is generated by sustained low-level overload current or quickly when the magnetic coil senses a high-current short circuit.
    QO Series
    Image of Product. QO Series, 2 Poles. Front orientation. Circuit Breakers. Square D Load-Center Circuit Breakers, QO Series, 2 Poles—Toggle Switch.

    QO Series,

    2 Poles

    UL 489—They meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits.
    Breakthrough Current @ Voltage—Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
    Current,
    A
    Voltage
    Freq., Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Wire Connection
    Method
    Wd.
    Specs.
    Met
    Certification
    Each
    2 Poles—Toggle Switch
    7048V DC
    120V AC
    240V AC    		50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K220000000
     

    Siemens Load-Center Circuit Breakers

    Image of Product. Front orientation. Circuit Breakers. Siemens Load-Center Circuit Breakers, 2 Poles—Toggle-Switch Style.

    2

    Poles—Toggle-Switch

    Style

    Use with Siemens EQ series breaker boxes. Because they are thermal-magnetic, these circuit breakers trip two different ways. They either trip when heat is generated slowly by consistent low-level overload current or quickly when the magnetic coil senses a high-current short circuit.
    UL 489—These circuit breakers meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits.
    Breakthrough Current @ Voltage—Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
    Current,
    A
    Voltage, V AC
    Freq.,
    Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Wire Connection
    Wd.
    Specs.
    Met
    Each
    2 Poles—Toggle-Switch Style
     
    Thermal/Magnetic
    70120
    240    		6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxScrew-Clamp Terminal2"UL 4895259T6000000
     

    Square D Secondary Circuit Breaker Boxes

    Image of Product. Front orientation. Circuit Breaker Boxes. Square D Secondary Circuit Breaker Boxes.
    Connect these boxes to a main box—they do not have a main circuit breaker switch. They are single-phase, 3-wire, and can be mounted for top or bottom feed conduit connections. Also known as load centers.
    NEMA 1 Enclosure Rating—NEMA 1 rated boxes are for indoor use.
    Breakthrough Current @ Voltage—Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
    Cover
    No. of
    Spaces
    Current,
    amp
    Voltage, V AC
    Freq., Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Bus Bar Material
    Attachment
    Style
    Closure
    Method
    Ht.
    Wd.
    Dp.
    Certification
    Each
    NEMA 1 Enclosure Rating
    270120/24050/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		SurfaceTin-Plated CopperLift Off
    		Screw9 1/4"4 7/8"3 1/4"UL Listed
    		6790K57000000
     
    Breakers
    Image of Product. QO Series, 1 Pole. Front orientation. QO Series. 1 Pole.
    Image of Product. QO Series, 2 Poles. Front orientation. QO Series. 2 Poles.
    Image of Product. QO Series, 3 Poles. Front orientation. QO Series. 3 Poles.

    QO

    Series, 1

    Pole

    QO Series,

    2 Poles

    QO Series, 3

    Poles

    Circuit breakers meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits.
    Ground Fault Sensitivity—Circuit breakers with ground fault sensitivity will trip if they detect a current leak above 6mA. This minimizes the risk of electric shock to workers and equipment.
    Current,
    amp
    Voltage
    Freq., Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Wire Connection
    Method
    Wd.
    Specs.
    Met
    Certification
    Each
    QO Series
     
    1 Pole—Toggle Switch
    15120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On3/4"UL 489UL Listed
    		6782K112000000
    20120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On3/4"UL 489UL Listed
    		6782K11300000
    30120V AC/240V AC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxSnap On3/4"UL 489UL Listed
    		6782K1200000
    40120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On3/4"UL 489UL Listed
    		6782K30100000
     
    2 Poles—Toggle Switch
    15120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21200000
    20120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21300000
    30120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21400000
    40120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21500000
    50120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21600000
    60120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K21700000
    70120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On1 1/2"UL 489UL Listed
    		6782K22000000
     
    3 Poles—Toggle Switch
    15120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On2 1/4"UL 489UL Listed
    		6782K306000000
    20120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On2 1/4"UL 489UL Listed
    		6782K307000000
    30120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On2 1/4"UL 489UL Listed
    		6782K308000000
    40120V AC/240V AC/48V DC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Breaker BoxSnap On2 1/4"UL 489UL Listed
    		6782K309000000
     
    QO Series with 6 mA Ground Fault Sensitivity
     
    1 Pole—Toggle Switch
    20120V AC50/6010,000 amp @ 120V ACBreaker BoxSnap On3/4"UL 489UL Listed
    		6782K302000000
    30120V AC50/6010,000 amp @ 120V ACBreaker BoxSnap On3/4"UL 489UL Listed
    		6782K303000000
     
    2 Poles—Toggle Switch
    20120V AC/240V AC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxSnap On1.5"UL 489UL Listed
    		6782K304000000
    30120V AC/240V AC50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxSnap On1.5"UL 489UL Listed
    		6782K305000000
     

    Cutler-Hammer Load-Center Circuit Breakers

    Image of Product. Front orientation. Circuit Breakers. Cutler-Hammer Load-Center Circuit Breakers, 2 Poles—Toggle-Switch Style.

    2

    Poles—Toggle-Switch

    Style

    Install these circuit breakers into Cutler-Hammer CH series breaker boxes. Because these circuit breakers are thermal-magnetic, they trip two different ways. They either trip when heat is generated slowly by consistent low-level overload current or quickly when the magnetic coil senses a high-current short circuit.
    UL 489—They meet UL 489 requirements for branch circuit protection and are certified as current limiting, so they protect equipment by minimizing passing current during a short circuit.
    Breakthrough Current @ Voltage—Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
    Current,
    A
    Voltage, V AC
    Freq.,
    Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Wire Connection
    Wd.
    Specs.
    Met
    Each
    2 Poles—Toggle-Switch Style
     
    Thermal/Magnetic
    70120
    240    		6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxScrew-Clamp Terminal1 1/2"UL 4895259T9000000
     

    Harsh-Environment Circuit Breakers

    Image of Product. Front orientation. Circuit Breakers. Harsh-Environment Circuit Breakers, 1 Pole—Push-Pull-Button Style.
    Image of Product. Front orientation. Circuit Breakers. Harsh-Environment Circuit Breakers, 1 Pole—Lever Style.
    Image of Product. Front orientation. Circuit Breakers. Harsh-Environment Circuit Breakers, 1 Pole—Push-Button Style.

    1

    Pole—Push-Pull-Button

    Style

    1

    Pole—Lever

    Style

    1

    Pole—Push-Button

    Style

    Built to resist vibration and corrosion in harsh environments, these circuit breakers protect against overload and short circuits in low-voltage automotive and other electronic applications. All are thermal, so they use the heat generated in overcurrent situations to trip the breaker.
    Lever Manual Reset and Push-Pull Button Manual Reset—Push-pull button and lever style breakers can be used as an on/off switch.
    UL 1077—Place UL 1077-rated breakers downstream from a branch circuit breaker to protect a single piece of equipment. They are also known as supplemental protectors.
    Breakthrough Current @ Voltage—Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
    Mounting
    Holes
    Screw On
    Current,
    A
    Voltage,
    V DC
    Breakthrough Current
    @ Voltage
    For Panel
    Cutout Dia.
    Dp. Behind
    Panel
    Mounting
    Location
    No.
    of
    Dia.
    Mounting Fasteners
    Included
    Wire
    Connection
    Ht.
    Wd.
    Dp.
    Temp. Range,
    ° F
    Specs.
    Met
    Certification
    Each
    1 Pole—Push-Pull-Button Style
     
    Thermal
    70286,000 amp @ 28V DC0.49"2.48"Panel——YesScrew Terminal———-65 to 165UL 1077UL Recognized Component
    		6608T18000000
     
    1 Pole—Lever Style
     
    Thermal
    70481,500 amp @ 48V DC———30.19"NoScrew Terminal3.44"2.32"1.72"-40 to 185—CE Marked
    		4514K22600000
     
    1 Pole—Push-Button Style
     
    Thermal
    70481,500 amp @ 48V DC———20.25"NoScrew Terminal2.89"1.9"1.44"-40 to 185—CE Marked
    		4514K13500000
     
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