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Molded & Insulated Case Circuit Breakers

Home > Store > Circuit Breakers > Molded & Insulated Case Circuit Breakers

Manufacturer
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Fixed Mount or Draw Out
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Indoor/Outdoor
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Poles
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Shunt Trip
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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.
Picture of SPB100 Westinghouse Pow-R Breaker 3000A 3P 600 VAC M/O F/M

SPB100 Westinghouse Pow-R Breaker 3000A 3P 600 VAC M/O F/M

Westinghouse SPB100 Pow-R breaker; 3000 amp, 600 volt AC, 3 pole. With 3000 amp rating plug DigiTrip 510, LSIG functions, ground fault, shunt trip- 120 volt AC, manually operated (M/O), used tested with report.
SKU: MCCB1173
$5,500.00
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Picture of SPB100 Westinghouse Pow-R-Way Breaker 2500 Amp 600 VAC E/O D/O

SPB100 Westinghouse Pow-R-Way Breaker 2500 Amp 600 VAC E/O D/O

Westinghouse SPB100 Pow-R-Way breaker; 2500 amp, 600 volt AC, 3 pole. With Digitrip RMS 600 cat.# T64ALIG, LIG functions, ground fault, 2500 amp rating plug cat.# PD6S25A250, shunt trip cat.# SPBSTEO024D- 24 VDC-8.0 @ .25 sec. DC, E/O (electrically operated)- cat.# SPBEO120A 120 VAC- 1.2 amps, 50/60 Hz, spring release- 120 VAC--2.5 amps, 50/60 Hz. D/O ( draw out), used tested with report.
SKU: MCCB1717
$4,800.00
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Picture of SPB100M Cutler- Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

SPB100M Cutler- Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

Cutler- Hammer/Westinghouse SPB100M breaker; cat.# SPBMR330C 3000 amp, 600 Volt AC, 3 pole. With Digitrip RMS 910 cat.# S95LSG, LSG functions, ground fault, 3000 amp rating plug cat.# RP6S30A300, electrically operated (E/O) cat.# SPBEOC120A, auxiliary switch cat.# SPBAUXC304, shunt trip cat.# SPBSTC024D, power relay module cat.# SPBAATR, draw-out (D/O), used tested with report.
SKU: MCCB1611
$8,100.00
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Picture of SPB100M Cutler-Hammer/Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

SPB100M Cutler-Hammer/Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

Cutler-Hammer/Westinghouse SPB100M circuit breaker; cat.# SPBMR316C, 1600 amp, 600 volt AC, 3 pole. With Digitrip RMS 910 cat.#S95LSG, LSG functions, ground fault, 1600 amp rating plug cat.# RP6S16A160, electrically operated (E/O) cat.#SPBEOC120A, spring release- 120 VAC, 2.5 amp, 50/60 HZ. With shunt trip- 24 VDC, cat.#SPBSTC024D, auxiliary switch cat.# SPBAUX164, power relay module cat #SPBAATR, draw-out (D/O), used tested with report.
SKU: MCCB1481
$3,000.00
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Picture of SPB100M Cutler-Hammer/Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

SPB100M Cutler-Hammer/Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

Cutler-Hammer/Westinghouse SPB100M circuit breaker; cat.# SPBMR316C, 1600 amp, 600 volt AC, 3 pole. With Digitrip RMS 910 cat.#S95LSG, LSG functions, ground fault, 1600 amp rating plug cat.# RP6S16A160, electrically operated (E/O) cat.#SPBEOC120A, spring release- 120 VAC, 2.5 amp, 50/60 HZ. With shunt trip- 24 VDC cat.#SPBSTC024D, auxiliary switch cat.# SPBAUX164, power relay module cat.# SPBAATR, draw-out (D/O), used tested with report.
SKU: MCCB1485
$3,000.00
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Picture of SPB100M Cutler-Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

SPB100M Cutler-Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

Cutler-Hammer/Westinghouse SPB100M breaker; cat.# SPBMR330C, 3000 amp, 600 volt AC, 3 pole. With 3000 amp rating plug cat# RP6S30A300, Digitrip RMS910 cat# S95LSG (D), auxiliary switch cat.# SPBAUXC304, shunt trip cat.# SPBSTC024D, power relay module cat.# SPBAATR, electrically operated (E/O) cat.# SPBEOC120A, spring release, draw-out (D/O), used tested with report.
SKU: MCCB1570
$7,500.00
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Picture of SPB100M Cutler-Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

SPB100M Cutler-Hammer/Westinghouse Breaker 3000 Amp 600 VAC E/O D/O

Cutler-Hammer/Westinghouse SPB100M breaker; cat.# SPBMR330C, 3000 amp, 600 volt AC, 3 pole. With Digitrip RMS 910 cat.#S95LSG, LSG functions, ground fault, 3000 amp rating plug cat.# RP6S30A300, electrically operated (E/O) cat.#SPBEOC120A, spring release- 120 VAC- 2.5 amp- 50/60 HZ, shunt trip- 24 VDC cat.#SPBSTC024D, auxiliary switch cat.# SPBAUXC304, power relay module cat.# SPBAATR, draw-out (D/O), used tested with report.
SKU: MCCB1488
$7,500.00
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Picture of SPB65 Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

SPB65 Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

Westinghouse SPB 65 circuit breaker; 1600 amp, 600 volt AC, 3 pole. With Pow-R Trip 7, LSIG functions, ground fault, 1600 amp rating plug cat.# 16SPB1600, shunt trip, auxiliary switch, electrical operator, spring release, electrically operated (E/O), draw out (D/O), used tested with report.
SKU: MCCB1768
$2,100.00
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Picture of SPB65 Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

SPB65 Westinghouse Breaker 1600 Amp 600 VAC E/O D/O

Westinghouse SPB 65 circuit breaker; 1600 amp, 600 volt AC, 3 pole. With Pow-R Trip 7, LSIG functions, ground fault, 1600 amp rating plug cat.# 16SPB1600, shunt trip, auxiliary switch, electric operator, spring release, electrically operated (E/O), draw out (D/O), used tested with report.
SKU: MCCB1770
$2,100.00
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Picture of SPBSR321R Cutler-Hammer Breaker 2000 Amp 600 VAC LI

SPBSR321R Cutler-Hammer Breaker 2000 Amp 600 VAC LI

Cutler-Hammer SPBSR321R Breaker SPB 65; 2000 amp, 600 volt AC, 3 pole. With digitrip RMS510 cat# S51LI (D), LI functions, 2000 amp rating plug cat# RP6S21A200, spring release, used tested with report.
SKU: MCCB1856
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Picture of Square D (Schneider) Masterpact NW50H Circuit Breaker 5000 Amp 600 VAC E/O F/M

Square D (Schneider) Masterpact NW50H Circuit Breaker 5000 Amp 600 VAC E/O F/M

Square D (Schneider) NW50H MasterPact circuit breaker: cat.#YG3LLX64A3SCBBXXXXY002 (Schneider) cat.# 244-9977, 5000 amp, three pole, 600 volt AC, 5000 amp rated. With Micrologic 6.0P trip unit with LSIG functions, ground fault protection, 100ka @ 480 volt, Modbus communication, spring charging motor - 24 VDC, shunt trip - 24 VAC/24 VDC, closing coil - 24 VAC/24 VDC, electrically operated (E/O), fixed mount (F/M), used tested with report.
SKU: MCCB1532
$35,000.00
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Picture of Square D (Schneider) Masterpact NW50H Circuit Breaker 5000 Amp 600 VAC E/O F/M

Square D (Schneider) Masterpact NW50H Circuit Breaker 5000 Amp 600 VAC E/O F/M

Square D (Schneider) NW50H MasterPact breaker: cat# YG3LLX64A3SCBBXXXXY002 (Schneider), cat.# 244-9977, 5000 amp, 5000 amp rated, 600 volt AC, three pole. With Micrologic 6.0P trip unit with LSIG functions, ground fault protection, 100ka @ 480 volt, Modbus communication, spring charging motor- 24 VDC, shunt trip - 24 VAC/24 VDC, closing coil - 24 VAC/24 VDC, electrically operated (E/O), fixed-mount (F/M), used tested with report.
SKU: MCCB1533
$35,000.00
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Picture of Square D MasterPact MP08H1 Circuit Breaker 800 Amp 600 Volt AC E/O D/O

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

Square D MasterPact MP08H1 Circuit Breaker; 800 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR58U trip unit, LSI functions, 800 amp rating plug, auxiliary switches, over current trip switch, alarm LT, shunt trip, closing release, & motor and "charged" switch. Used tested with report.
SKU: MCCB2232
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Picture of Square D MasterPact MP08H1 Circuit Breaker 800 Amp 600 Volt AC E/O D/O

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

Square D MasterPact MP08H1 Circuit Breaker; 800 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR58U trip unit, LSI functions, 800 amp rating plug- cat # 54746, auxiliary switches, overcurrent trip switch, LT alarm, shunt trip, closing release, & motor and "charged" switch. Used tested with report.
SKU: MCCB2234
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Picture of Square D MasterPact MP08H1 Circuit Breaker 800 Amp 600 Volt AC E/O D/O

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

Square D MasterPact MP08H1 Circuit Breaker; 800 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR58U trip unit, LSI functions, 800 amp rating plug- cat # 54746, auxiliary switches, overcurrent trip switch, LT alarm, shunt trip, closing release, & motor and "charged" switch. Used tested with report.
SKU: MCCB2235
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Picture of Square D Masterpact MP12H1 Circuit Breaker 1200 Amp 600 VAC D/O E/O

Square D Masterpact MP12H1 Circuit Breaker 1200 Amp 600 VAC D/O E/O

Square D MP12H1 Masterpact circuit breaker; 1200 amp, 600 volt AC, 3 pole. With STR 58U trip unit with LSIG functions, ground fault, 1200 amp rating plug cat.# 54750, auxiliary switch, shunt trip, overcurrent trip switch, LT alarm, motor & charged switch, closing release, Ext. CT, draw-out (D/O), electrically operated (E/O), used tested with report.
SKU: MCCB1796
$4,500.00
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Picture of Square D MasterPact MP12H1 Circuit Breaker 1200 Amp 600 Volt AC E/O D/O

Square D MasterPact MP12H1 Circuit Breaker 1200 Amp 600 Volt AC E/O D/O

Square D MasterPact MP12H1 Circuit Breaker; 1200 amp, 600 volt AC, 3 pole, electrically operated (E/O), draw-out (D/O). With STR58U trip unit, LSI functions, 1200 amp rating plug- cat # 54750, auxiliary switches, over current trip switch, LT alarm, shunt trip, closing release, & motor and "charged" switch. Used tested with report.
SKU: MCCB2233
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Picture of Square D Masterpact MP12H2 Circuit Breaker 1200 Amp 600 VAC E/O F/M

Square D Masterpact MP12H2 Circuit Breaker 1200 Amp 600 VAC E/O F/M

Square D MP12H2 Masterpact circuit breaker; 1200 amp, 600 volt AC, 3 pole. With 800 amp rating plug cat.#54748, STR58U trip unit, LSI functions, shunt trip, auxiliary switches, overcurrent trip switch, under voltage release, alarm switch, electrically operated (E/O), motor and "charged" switch, closing release, fixed-mount (F/M), used tested with report.
SKU: MCCB1393
$4,500.00
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Picture of Square D Masterpact MP16H1 Circuit Breaker 1600 Amp 600 VAC E/O D/O

Square D Masterpact MP16H1 Circuit Breaker 1600 Amp 600 VAC E/O D/O

Square D MP16H1 Masterpact circuit breaker; 1600 amp, 600 volt AC, 3 pole. With STR 58 U trip unit, LSI functions, 1600 amp rating plug cat.# 54754, auxiliary switches, shunt trip- 24 VDC, electrically operated (E/O), draw out (D/O), used tested with report.
SKU: MCCB1665
$3,300.00
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Picture of Square D MasterPact MP16H1 Circuit Breaker 1600 amp 600 Volt AC D/O E/O

Square D MasterPact MP16H1 Circuit Breaker 1600 amp 600 Volt AC D/O E/O

Square D MasterPact MP16H1 Circuit Breaker; 1600 amp, 600 volt AC, 3 pole, draw-out (D/O), electrically operated (E/O). With STR58U trip unit, LSI functions, 1600 amp rating plug- cat # 54754, auxiliary switches, over current trip switch, alarm LT, shunt trip, closing release, under voltage release, & motor and "charged" switch. Used tested with report.
SKU: MCCB2231
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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.