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    13 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
    6048V 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
    		6782K217000000
     
    QOB Series
    Image of Product. QOB Series, 3 Poles. Front orientation. Circuit Breakers. Square D Load-Center Circuit Breakers, QOB Series, 3 Poles—Toggle Switch.

    QOB Series,

    3 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
    Wd.
    Specs.
    Met
    Certification
    Each
    3 Poles—Toggle Switch
    6048V DC
    120V AC
    240V AC    		50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    5,000 amp @ 48V DC    		Panel BoardScrew-Clamp Terminal2 1/4"UL 489UL Listed
    		6782K3140000000
     
    Homeline Series
    Image of Product. Homeline Series, 3 Poles. Front orientation. Circuit Breakers. Square D Load-Center Circuit Breakers, Homeline Series, 2 Poles—Toggle Switch.

    Homeline

    Series, 3

    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, V AC
    Freq., Hz
    Breakthrough Current @ Voltage
    Mounting
    Location
    Wire Connection
    Method
    Wd.
    Specs.
    Met
    Certification
    Each
    2 Poles—Toggle Switch
    60120
    240    		50/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxSnap On2"UL 489UL Listed
    		69225K103000000
     

    High-Power Circuit Breakers

    Image of Product. Shunt Trip. Front orientation. Circuit Breakers. High-Power Circuit Breakers.

    Shunt

    Trip

    Image of Product. Circuit Breaker. Front orientation. Circuit Breakers. High-Power Circuit Breakers.

    Circuit

    Breaker

    Image of Product. Undervoltage Trip. Front orientation. Circuit Breakers. High-Power Circuit Breakers.

    Undervoltage

    Trip

    Protect an area of a facility that has high-powered equipment. These circuit breakers are also known as molded case circuit breakers. Because these breakers are thermal-magnetic, they trip two ways. They either trip when heat is generated slowly by consistent low-level overload current, or they trip quickly when the magnetic coil senses a high-current short circuit. A switch lets you adjust when these breakers magnetically trip, so you don't need to replace them as your application changes. These breakers have internal accessory slots to fit shunt trips, auxiliary contacts, and undervoltage trips, saving space in your setup.
    Undervoltage trips protect equipment from operating with less than their intended voltage by tripping a circuit breaker when the supply voltage drops below a set level. 30 amp to 250 amp breakers can only have one shunt trip or undervoltage trip installed. 400 amp to 600 amp breakers can accommodate one shunt trip and one undervoltage trip at the same time.
    Shunt trips receive a signal from equipment to trip your circuit breaker in situations other than overload or short circuit conditions. For example, use them with a smoke detector to shut off power to a system in the event of a fire. 30 amp to 250 amp breakers can only have one shunt trip or undervoltage trip installed. 400 amp to 600 amp breakers can accommodate one shunt trip and one undervoltage trip at the same time.
    UL 489—They meet UL 489 requirements for branch circuit protection.
    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
    Freq., Hz
    Breakthrough Current @ Voltage
    Inrush Current Setting, amp
    For DIN
    Rail Size, mm
    Mounting
    Location
    No.
    of
    Dia.
    Mounting Fasteners
    Included
    Wire
    Connection
    Ht.
    Wd.
    Dp.
    Temp. Range,
    ° F
    Specs. Met
    Certification
    Each
    3 Poles—Toggle-Switch Style
     
    Thermal/Magnetic
    60600V DC
    480V AC
    600YV AC/347V AC    		50/6065,000 amp @ 240V AC
    25,000 amp @ 480V AC
    14,000 amp @ 600V AC
    14,000 amp @ 125V DC
    50,000 amp @ 250V DC
    50,000 amp @ 500V DC
    50,000 amp @ 600V DC    		300, 360, 420, 480, 540, 60035DIN Rail411/64"YesTab5.5"3"3"-10 to 155UL 489, IEC 60947-2, IEC 81346-2UL Listed, CE Marked
    		4434N120000000
     
    Accessories for Circuit Breakers
    Shunt Trips
    Voltage,
    V AC
    Current @
    Voltage
    Freq., Hz
    Wire Connection
    Ht.
    Wd.
    Dp.
    Temp. Range,
    ° F
    Specs. Met
    Certification
    Each
    110 to 1277.4 amp @ 110V AC50/60Screw-Clamp Terminal2.56"0.85"1.23"-10 to 155UL 489, IEC 60947-2UL Listed
    		4434N220000000
    Auxiliary Contacts
    Image of Product. Front orientation. Circuit Breaker Auxiliary Contacts. High-Power Circuit Breakers.
    Auxiliary contacts send a signal to other equipment when the circuit trips. They can activate a warning light, initiate a shutdown, or start a backup power source. Multiple auxiliary contacts can be used within one circuit breaker and can be placed in any of the accessory slots.
    Voltage
    Current,
    amp
    Freq., Hz
    Switch
    Designation
    No. of Circuits
    Controlled
    Switch Starting
    Position
    Wire Connection
    Ht.
    Wd.
    Dp.
    Temp. Range,
    ° F
    Specs. Met
    Certification
    Each
    24V AC to 300V AC/24V DC to 250V DC650/60DPST
    		21 Off and 1 On
    		Screw-Clamp Terminal2.57"0.28"1.36"-10 to 155UL 489, IEC 60947-2UL Listed
    		4434N230000000
    Undervoltage Trips
    Voltage,
    V AC
    Current @ Voltage
    Freq., Hz
    Wire Connection
    Ht.
    Wd.
    Dp.
    Temp. Range,
    ° F
    Specs. Met
    Certification
    Each
    120 to 1270.01 amp @ 120V AC50/60Screw-Clamp Terminal2.56"1.01"1.13"-10 to 155UL 489, IEC 60947-2UL Listed
    		4434N240000000
    Circuit Breaker Handles
    Image of Product. Front orientation. Circuit Breaker Handles. High-Power Circuit Breakers.
    Install handles on the front cover of an electrical cabinet to turn these breakers on, off, or reset them without having to open the cabinet. Yet, these handles won’t prevent you from opening the electrical cabinet normally. You can also lock the handles in the on or off position with a padlock (not included) to prevent unauthorized changes to the circuit breaker.
    For Circuit Breaker
    Current, amp
    Ht.
    Wd.
    Projection
    Mounting Fasteners
    Included
    For Max. Padlock
    Shackle Dia.
    Padlock
    Included
    Temp. Range,
    ° F
    Enclosure Rating
    Specs. Met
    Each
    30, 60, 100, 1252.95"2.95"2.16"Yes3/8"No-10 to 155IP65, NEMA 4X, NEMA 12
    		IEC 60947-24434N250000000

    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
    60120
    240    		6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxScrew-Clamp Terminal2"UL 4895259T56000000
     

    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
    60286,000 amp @ 28V DC0.49"2.48"Panel——YesScrew Terminal———-65 to 165UL 1077UL Recognized Component
    		6608T17000000
     
    1 Pole—Lever Style
     
    Thermal
    60481,500 amp @ 48V DC———30.19"NoScrew Terminal3.44"2.32"1.72"-40 to 185—CE Marked
    		4514K22500000
     
    1 Pole—Push-Button Style
     
    Thermal
    60481,500 amp @ 48V DC———20.25"NoScrew Terminal2.89"1.9"1.44"-40 to 185—CE Marked
    		4514K13400000
     

    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
    60120
    240    		6010,000 amp @ 120V AC
    10,000 amp @ 240V AC    		Breaker BoxScrew-Clamp Terminal1 1/2"UL 4895259T86000000
     
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