Square D Load-Center Circuit Breakers
Match these circuit breakers to Square D breaker boxes or panel boards of the same manufacturer series. They meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits. 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.
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.
Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
For technical drawings and 3-D models, click on a part number.
| Current, A | Voltage | Frequency, Hz | Breakthrough Current | Mounting Location | Wire Connection Type | Wd. | Specifications Met | Each | |
QO Series | |||||||||
|---|---|---|---|---|---|---|---|---|---|
1 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 00000 |
| 30 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 0000000 | 00000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 00000 |
2 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 30 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 50 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 60 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 70 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 0000000 | 000000 |
3 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
QO Series with 6mA Ground Fault Sensitivity | |||||||||
1 Pole—Toggle Style | |||||||||
| 20 | 120V AC | 50/60 | 10,000 A @ 120 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC | 50/60 | 10,000 A @ 120 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
2 Pole—Toggle Style | |||||||||
| 20 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 000000 |
Siemens Load-Center Circuit Breakers
Use with Siemens EQ series breaker boxes. These circuit breakers meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits. Because they 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.
Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
| Current, A | Voltage | Frequency, Hz | Breakthrough Current | Wire Connection Type | Wd. | Specifications Met | Each | |
2 Pole—Toggle Style | ||||||||
|---|---|---|---|---|---|---|---|---|
| 70 | 120V AC/240V AC | 60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Screw-Clamp Terminals | 2" | UL 489 | 000000 | 000000 |
Cutler-Hammer Load-Center Circuit Breakers
Install these circuit breakers into Cutler-Hammer CH series breaker boxes. They meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits. 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.
Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
| Current, A | Voltage | Frequency, Hz | Breakthrough Current | Wire Connection Type | Wd. | Specifications Met | Each | |
2 Pole—Toggle Style | ||||||||
|---|---|---|---|---|---|---|---|---|
| 70 | 120V AC/240V AC | 60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Screw-Clamp Terminals | 1 1/2" | UL 489 | 000000 | 000000 |
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 rated boxes are for indoor use.
Circuit breakers meet UL 489 requirements for branch circuit protection, so they protect downstream equipment and wiring from overloads and short circuits. 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.
Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
Cover | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Number of Spaces | Current, A | Voltage | Frequency, Hz | Breakthrough Current | Mounting Style | Bus Bar Material | Attachment Style | Closure Method | Ht. | Wd. | Dp. | Specifications Met | Each | |
NEMA 1 Rated | ||||||||||||||
| 2 | 70 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Surface | Tin-Plated Copper | Lift Off | Screws | 9 1/4" | 4 7/8" | 3 1/4" | UL Listed | 0000000 | 000000 |
| Current, A | Voltage | Frequency, Hz | Breakthrough Current | Mounting Location | Wire Connection Type | Wd. | Specifications Met | Each | |
QO Series | |||||||||
|---|---|---|---|---|---|---|---|---|---|
1 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 00000 |
| 30 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 0000000 | 00000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 00000 |
2 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 30 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 50 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 60 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 00000 |
| 70 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 0000000 | 000000 |
3 Pole—Toggle Style | |||||||||
| 15 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 20 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
| 40 | 120V AC/240V AC/48V DC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC 5,000 A @ 48 V DC | Breaker Box | Snap On | 2 1/4" | UL 489, UL Listed | 00000000 | 000000 |
QO Series with 6mA Ground Fault Sensitivity | |||||||||
1 Pole—Toggle Style | |||||||||
| 20 | 120V AC | 50/60 | 10,000 A @ 120 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC | 50/60 | 10,000 A @ 120 V AC | Breaker Box | Snap On | 3/4" | UL 489, UL Listed | 00000000 | 000000 |
2 Pole—Toggle Style | |||||||||
| 20 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 000000 |
| 30 | 120V AC/240V AC | 50/60 | 10,000 A @ 120 V AC 10,000 A @ 240 V AC | Breaker Box | Snap On | 1 1/2" | UL 489, UL Listed | 00000000 | 000000 |
Harsh-Environment Circuit Breakers
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.
Breakthrough current is the maximum current that the circuit breaker can safely stop in the event of a short circuit.
Push-pull button and lever style breakers can be used as an on/off switch.
Place UL1077 rated breakers downstream from a branch circuit breaker to protect a single piece of equipment. They are also known as supplemental protectors.
For technical drawings and 3-D models, click on a part number.
| Current, A | Voltage | Breakthrough Current | For Panel Cutout Dia. | Dp. Behind Panel | Mount Type | Mounting Fasteners Included | Wire Connection Type | Temp. Range, °F | Specifications Met | Each | |
1 Pole | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 70 | 28V DC | 6,000 A @ 28 V DC | 0.49" | 2.48" | Screw On | Yes | Screw Terminals | -65° to 165° | UL 1077, UL Recognized Component | 0000000 | 000000 |
Mounting Holes | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Current, A | Voltage | Breakthrough Current | Ht. | Wd. | Dp. | Mount Type | No. of | Dia. | Mounting Fasteners Included | Wire Connection Type | Temp. Range, °F | Specifications Met | Each | |
1 Pole | ||||||||||||||
| 70 | 48V DC | 1,500 A @ 48 V DC | 3.44" | 2.32" | 1.72" | Screw On | 3 | 0.19" | No | Screw Terminals | -40° to 185° | CE Marked | 00000000 | 000000 |
Mounting Holes | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Current, A | Voltage | Breakthrough Current | Ht. | Wd. | Dp. | Mount Type | No. of | Dia. | Mounting Fasteners Included | Wire Connection Type | Temp. Range, °F | Specifications Met | Each | |
1 Pole | ||||||||||||||
| 70 | 48V DC | 1,500 A @ 48 V DC | 2.89" | 1.9" | 1.44" | Screw On | 2 | 0.25" | No | Screw Terminals | -40° to 185° | CE Marked | 00000000 | 000000 |