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    45 Products

    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.
    NEMA 3R Enclosure Rating—NEMA 3R rated boxes are for outdoor 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
    12125120/24050/6065,000 amp @ 120V AC
    65,000 amp @ 240V AC
    SurfaceTin-Plated CopperLift Off
    Screw17 7/8"14 1/4"3 3/4"UL Listed
    00000000000000
     
    NEMA 3R Enclosure Rating
    12125120/24050/6065,000 amp @ 120V AC
    65,000 amp @ 240V AC
    SurfaceTin-Plated CopperHinged
    Quick-Release Latch18 7/8"14 3/4"4 1/2"UL Listed
    0000000000000
    24125120/24050/6065,000 amp @ 120V AC
    65,000 amp @ 240V AC
    SurfaceTin-Plated CopperHinged
    Quick-Release Latch22"14 3/4"4 1/2"UL Listed
    0000000000000
     
    Breakers

    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
    125600V 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
    625; 750; 875; 1,000; 1,125; 1,25035DIN Rail411/64"YesTab Terminal5.5"3"3"-10 to 155UL 489, IEC 60947-2, IEC 81346-2UL Listed, CE Marked
    0000000000000000
     
    Accessories for Circuit Breakers

    Square D Homeline Secondary Circuit Breaker Boxes

    Image of Product. Front orientation. Circuit Breaker Boxes. Square D Homeline 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
    Profile
    Mounting
    Location
    Bus Bar Material
    Attachment
    Style
    Closure
    Method
    Ht.
    Wd.
    Dp.
    Certification
    Each
    NEMA 1 Enclosure Rating
    12125120/24050/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    RecessedSurfaceTin-Plated AluminumLift Off
    Screw17 7/8"14 1/4"3 3/4"UL Listed
    0000000000000
    20125120/24050/6010,000 amp @ 120V AC
    10,000 amp @ 240V AC
    RecessedSurfaceTin-Plated AluminumLift Off
    Screw26"14 1/4"3 3/4"UL Listed
    000000000000
     
    Breakers

    Square D Homeline Main Circuit Breaker Boxes

    Image of Product. Front orientation. Circuit Breaker Boxes. Square D Homeline Main Circuit Breaker Boxes .
    With a main breaker installed and main service knockouts, these boxes are the entry point for electricity into your facility and the first step in protecting your electrical systems. 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—Boxes are rated NEMA 1 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
    Profile
    Mounting
    Location
    Bus Bar Material
    Attachment
    Style
    Closure
    Method
    Ht.
    Wd.
    Dp.
    Certification
    Each
    NEMA 1 Enclosure Rating
    24125120/24050/6022,000 amp @ 120V AC
    22,000 amp @ 240V AC
    RecessedSurfaceTin-Plated AluminumLift Off
    Screw26"14 1/4"3 3/4"UL Listed
    00000000000000
     
    Breakers
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