Molded & Insulated Case Circuit Breakers

While our website showcases a large assortment of our products, it does not reflect the complete inventory of products currently available. For real-time availability and to ensure we can meet your specific needs, please contact our sales team at 1-800-328-1842. New products arrive daily and our knowledgeable staff are happy to assist you in locating the exact item(s) you need.

LH36125 Square D I-Line Circuit Breaker

Square D LH36125 I-Line circuit breaker; 125 amp, 600 volt, three pole, used tested with report.
SKU: LH36125
$2,200.00

LH36150 Square D I-Line Circuit Breaker

Square D LH36150 I-Line circuit breaker; 150 amp, 600 volt, three pole, used tested with report.
SKU: LH36150
$2,200.00

LH36175 Square D I-Line Circuit Breaker

Square D LH36175 I-Line circuit breaker; 175 amp, 600 volt, three pole, used tested with report.
SKU: LH36175
$2,200.00

LH36200 Square D I-Line Circuit Breaker

Square D LH36200 I-Line circuit breaker; 200 amp, 600 volt, three pole, used tested with report.
SKU: LH36200
$2,200.00

LH36225 Square D I-Line Circuit Breaker

Square D LH36225 I-Line circuit breaker; 225 amp, 600 volt, three pole, used tested with report.
SKU: LH36225
$2,200.00

LH36250 Square D I-Line Circuit Breaker

Square D LH36250 I-Line circuit breaker; 250 amp, 600 volt, three pole, used tested with report.
SKU: LH36250
$2,200.00

LH36300 Square D I-Line Circuit Breaker

Square D LH36300 I-Line circuit breaker; 300 amp, 600 volt, three pole, used tested with report.
SKU: LH36300
$2,200.00

LH36350 Square D I-Line Circuit Breaker

Square D LH36350 I-Line circuit breaker; 350 amp, 600 volt, three pole, used tested with report.
SKU: LH36350
$2,200.00

LH36400 Square D I-Line Circuit Breaker

Square D LH36400 I-Line circuit breaker; 400 amp, 600 volt, three pole, used tested with report.
SKU: LH36400
$2,200.00

Merlin Gerin Masterpact MP08 H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat# 54745, STR 28 D trip unit, auxiliary switches, overcurrent trip switch, alarm, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1779
$1,500.00

Merlin Gerin Masterpact MP08 H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat.# 54745, STR 28 D trip unit, auxiliary switches, overcurrent trip switch, alarm, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1780
$1,500.00

Merlin Gerin Masterpact MP08 H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat.# 54745, STR 28 D trip unit, auxiliary switches, overcurrent trip switch, alarm, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1782
$1,500.00

Merlin Gerin Masterpact MP08 H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat.# 54745, STR 58 U trip unit, LSI functions, auxiliary switches, overcurrent trip switch, alarm, shunt trip, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1783
$1,500.00

Merlin Gerin Masterpact MP08 H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat.# 54745, STR 28 D trip unit, auxiliary switches, overcurrent trip switch, alarm, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1786
$1,500.00

Merlin Gerin Masterpact MP08H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08 H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole. With 600 amp rating plug cat.# 54745, STR 28 D trip unit, auxiliary switches, overcurrent trip switch, alarm, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1781
$1,500.00

Merlin Gerin Masterpact MP08H1 Circuit Breaker 800 Amp 600 VAC M/O D/O

Merlin Gerin MP08H1 Masterpact circuit breaker; 800 amp, 600 volt AC, 3 pole With 600 amp rating plug cat # 54745, STR 58 U trip unit, LSI functions, auxiliary switches, overcurrent trip switch, alarm, shunt trip, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1784
$1,500.00

Merlin Gerin MasterPact MP08H1 Circuit Breaker 800 Amp 600 Volt AC E/O D/O

Merlin Gerin MasterPact MP08H1 Circuit Breaker; 800 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR 58 U trip unit, LSI functions. Used tested with a report.
SKU: MCCB2134
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Merlin Gerin MasterPact MP12H1 Circuit Breaker 1200 Amp 600 Volt AC E/O D/O

Merlin Gerin MasterPact MP12H1 Circuit Breaker; 1200 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR 58 U trip unit, LSI functions. Used tested with report.
SKU: MCCB2136
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Merlin Gerin MasterPact MP12H1 Circuit Breaker 1200 Amp 600 Volt AC E/O D/O

Merlin Gerin MasterPact MP12H1 Circuit Breaker; 1200 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR 58U trip unit, LSI functions. Used tested with a report.
SKU: MCCB2137
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Merlin Gerin MasterPact MP12H1 Circuit Breaker 1200A 600 VAC M/O D/O

Merlin Gerin MasterPact MP12H1 Circuit Breaker; 1200 amp, 600 volt AC, 3 pole. With STR 38 S trip unit, LSI functions, 1000 amp rating plug cat# 54749, shunt trip, auxiliary switches, LT alarm, overcurrent trip switch, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1967
Contact us for pricing:

New, Used, and Tested Molded & Insulated Case Circuit Breakers

EMSCO has been specializing in used and refurbished molded & insulated case circuit breakers for over 72 years.


Why Choose EMSCO for Molded Case or Insulated Case Circuit Breakers?

Want to match and replace your existing breakers? End the hassle of retrofitting your electrical system. Our extensive inventory includes a variety of Molded Case Circuit Breakers (MCCBs) and Insulated Case Circuit Breakers that are designed to seamlessly match and replace your existing breakers by brand, amp rating, voltage, frame size, or model.

New and Refurbished Products in Stock

We understand that budgets and preferences differ, so we give you the option of selecting between new and refurbished MCCBs or Insulated Case Breakers, both of which are readily available in our inventory. Choose brand-new circuit breakers for maximum performance and longevity, or look into our refurbished options, which have been rigorously tested and reconditioned to meet industry standards.

Popular Brands and Common Configurations

Our shelves are stocked with breakers from the most trusted and popular brands in the industry, ensuring you have access to dependable products. You'll find common configurations, such as different frame sizes and voltage ratings, making it simple to find the right circuit protection for your application.

Avoiding Costly Operational Downtime

Downtime can be an expensive situation. Our circuit protection products are designed for high performance and durability. You can avoid costly operational downtime due to electrical failures by using our fully-tested Molded Case or Insulated Case breakers. Our products provide reliable power and superior equipment protection.

Electrical Testing Equipment Certifying Quality and Performance

When it comes to the dependability and safety of your electrical systems, we leave nothing to chance. Our breakers are rigorously tested using current testing equipment to ensure that they meet or exceed industry standards. This ensures that your electrical installations are safe and efficient.

  • Overcurrent Protection: We verify that your breakers provide accurate overcurrent protection, guaranteeing the safety of your electrical systems.
  • Trip Time: We measure the time it takes for breakers to respond to overcurrent conditions, ensuring it operates within the specified trip time.
  • Short-Circuit Withstand Capacity: Our testing evaluates the breaker’s ability to withstand short-circuit currents, preventing damage and maintaining safety.
  • Interrupting Capacity: We determine the MCCB's capability to interrupt fault currents, ensuring the utmost protection for your electrical system.

Molded Case Circuit Breaker Specifications

A sample table of ampere ratings, corresponding voltage ratings, and frame sizes for molded case circuit breakers is shown below. Please keep in mind that frame sizes and ratings can differ between manufacturers and models. For precise details on a specific MCCB, always refer to the manufacturer's specifications.

Frame Size

Ampere Rating

Voltage Rating

A

15A

120V, 240V

A

20A

120V, 240V

B

30A

120V, 240V, 480V

B50A120V, 240V, 480V
C60A240V, 480V
C100A240V, 480V
D150A240V, 480V, 600V
D200A240V, 480V, 600V
E250A240V, 480V, 600V
E300A240V, 480V, 600V
F400A240V, 480V, 600V
F600A240V, 480V, 600V
G800A240V, 480V, 600V
G1200A240V, 480V, 600V
H1600A240V, 480V, 600V

This table is a sample representation of frame sizes, ampere ratings, and voltage ratings for Molded Case Circuit Breakers, not an exhaustive list.

Molded case circuit breakers (MCCBs) and insulated case circuit breakers (ICCBs) are two distinct types of circuit protection devices used in electrical systems. Both serve the purpose of interrupting electrical currents in case of faults or overloads, but they differ in construction, application, and performance characteristics. Need Help Now? Call 800-328-1842.