Browse Store Molded & Insulated Case Circuit Breakers
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- I - Instantaneous
- LI - Long-Time and Instantaneous
- IG - Instantaneous and Ground
- LIG - Long-Time, Instantaneous, Ground
- LS - Long-Time and Short-Time
- LSG - Long-Time, Short-Time, Ground
- LSI - Long-Time, Short-Time, Instantaneous
- LSIG - Long-Time, Short-Time, Instantaneous, Ground
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.
WLF3A340 Siemens 4000A Frame 4000A Rated 600V Power Circuit Breaker M/O D/O
Siemens low voltage AC integrally fused WLF3A340 power circuit breaker: 4000 amp frame, 600 volt, 4000 amp rating plug. Integrated cubicle bus trip unit ETU745, LSIG functions, manually operated (M/O), draw out (D/O) in cell - WLFG2340, used tested with report.
SKU: AB201421211
$15,000.00
WLF3A340 Siemens 4000A Frame 4000A Rated 600V Power Circuit Breaker M/O D/O
Siemens low voltage AC Integrally fused WLF3A340 power circuit breaker; 4000 amp frame, 600 volt, 4000 amp rating plug. Integrated cubicle bus trip unit ETU745, LSIG functions, manually operated (M/O), draw out (D/O) In cell - WLFG2340, used tested with report.
SKU: AB201421212
$15,000.00
WLF3A340 Siemens 4000A Frame 4000A Rated 600V Power Circuit Breaker M/O D/O
Siemens low voltage AC Integrally fused WLF3A340 power circuit breaker: 4000 amp frame, 600 volt, 4000 amp rating plug. Integrated cubicle bus trip unit ETU745, LSIG functions, manually operated (M/O), draw out (D/O) in cell - WLFG2340, used tested with report.
SKU: AB201421213
$15,000.00
TCYY9640E1C GE Power Break Molded Case Switch 4000 Amp 600 Volt E/O
General Electric TCYY9640E1C GE Power Break, molded case switch; 4000 amp, 600 Volt AC with auxiliaries, control voltage 120 volt AC, electrically operated (E/O) with shunt trip 120 to 240 volt AC, used tested with report.
SKU: MCCB1025
$7,200.00
TC4040TTE1CR GE Power Break Circuit Breaker 4000 Amp 600 VAC E/O D/O
General Electric TC4040TTE1CR Power Break circuit breaker; 4000 amp, 600 volt AC, 3 pole. With Micro Versa Trip cat.# C440LSIHGMR, 4000 amp rating plug. cat.# TR40B4000, shunt trip 120 to 240 volt AC, 50/60 HZ, auxiliary switches, bell alarm switch, electrically operated (E/O), draw-out (D/O), used tested with report.
SKU: MCCB1468
$15,000.00
TC4040TTE1CR GE Power Break Breaker 4000 Amp 600 VAC E/O D/O
General Electric TC4040TTE1CR Power Break; 4000 amp, 600 volt AC, 3 pole. Micro Versa Trip, cat.#TT40LSI, LSI functions, 4000 amp rating plug. Cat.# TR40B (2) auxiliary switches, bell alarm, shunt trip- 24 volt DC, electrically operated (E/O), 120 volt control voltage, draw-out (D/O), used tested with report.
SKU: MCCB1635
$9,000.00
TC4040TTE1CR GE Power Break Circuit Breaker 4000 Amp 600 VAC E/O D/O
General Electric TC4040TTE1CR Power Break circuit breaker; 4000 amp, 600 volt AC, 3 pole. With micro versa trip PM cat.#C440LSIM, 3000 amp rating plug. cat.# TR40B3000, shunt trip 120 to 240 volt AC, 50/60 HZ, auxiliary switches, bell alarm switch, control voltage 120 volt AC, electrically operated (E/O), draw-out (D/O), used tested with report.
SKU: MCCB1466
$15,000.00
THCMM9640 GE Power Break Breaker 4000 Amp 600 VAC M/O D/O
General Electric THCMM9640 Power Break Circuit Breaker; 4000 amp, 600 VAC, 3 pole, manually operated (M/O), draw-out (D/O) cubicle cat.# TDOS40, used tested with report.
SKU: MCCB1794
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SED364000LSGS1A8 Square D Breaker 4000 Amp 600 VAC
Square D SED364000LSGS1A8 breaker; 4000 amp with 3000 amp rating plug cat.#ARP075, shunt trip, micro logic full function series B with LSIG, ground fault, 600 VAC, used tested with report.
SKU: MCCB1377
$18,000.00
SBS4000 Siemens Breaker 4000 Amp 600 VAC MO/STA
Siemens SBS 4000 breaker; cat.# SBS4040F, 4000 amp, 600 volt AC, 3 pole. With trip unit cat.# SB40TLSIG, LSIG functions, ground fault, 3000 amp rating plug, manually operated, stationary, used tested with report.
SKU: MCCB24538
$18,000.00
SBH 4000 Siemens SBH4040 Circuit Breaker 4000 Amp 600 VAC MO/FM
Siemens SBH 4000 breaker cat.# SBH4040, 4000 amp trip unit cat.# SB40TLSIG with LSIG functions, 4000 amp rating plug, 600 VAC, manually operated, fixed mount, used tested with report.
SKU: MCCB22309
$21,000.00
M40H1 Merlin-Gerin Masterpact Circuit Breaker 4000 Amp 600 VAC M/O D/O
Merlin-Gerin M40H1 Masterpact circuit breaker: 4000 amp, 600 volt AC. STR58U trip unit with LSIG, ground fault, manually operated (M/O), draw-out (D/O) with draw-out cubicle, used tested with report.
SKU: MCCB1379
$15,000.00
Square D Masterpact NW40H Circuit Breaker 4000 Amp 600 VAC E/O D/O
Square D NW40H MasterPact circuit breaker: cat.#YL3KKR64A3DFBBWPCAT, 4000 amp frame, 600 volt AC, three pole, 4000 amp rating plug, Micro logic 6.0P trip with LSIG functions, ground fault, mod bus, spring charging motor- 100-130 VAC, shunt trip- 24-30 VAC/DC, closing coil -24-30 VAC/DC, 2nd OC trip switch, electrically operated (E/O), draw-out (D/O), used tested with report.
SKU: MCCB1528
$21,000.00
Square D Masterpact NW40H2 Circuit Breaker 4000 Amp 600 VAC E/O D/O
Square D NW40H2 MasterPact circuit breaker: cat.# YA5KKR63A3SFBFXXXX, 4000 amp frame, 600 volt AC, three pole, 4000 amp rated. 85kA @ 480V, Micrologic 5.0 P trip unit with LSI functions, Modbus, spring charging motor- 100-130 Volt AC/DC, shunt trip- 24-30 Volt AC/DC, closing coil - 100-130 VAC/DC, electrically operated (E/O), draw-out (D/O), used tested with report.** Small Chip in Bottom RT. Corner**.
SKU: MCCB1506
$21,600.00
TC4040SSH GE Power Break Circuit Breaker 4000 Amp 600 VAC M/O D/O
General Electric TC4040SSH Power Break circuit breaker; Micro Versa Trip RMS-9 with LSIG functions, ground fault, 4000 amp rating plug cat.# TR40S4000, 4000 amp shunt trip, auxiliary switch, 600 VAC, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1473
$15,000.00
Square D MasterPact NW40H2 Circuit Breaker 4000 Amp 600 VAC M/O D/O
Square D NW40H2 MasterPact circuit breaker; cat # YA5KJR44A9SXXXXXXA, 4000 amp, 600 volt AC, three pole. With Micrologic 6.0 amp trip unit, LSIG functions, ground fault, 3200 amp rating plug, key interlock, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1930
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Square D MasterPact NW40H2 Circuit Breaker 4000 Amp 600 VAC M/O D/O
Square D NW40H2 MasterPact circuit breaker; cat# YA5KJR44A9SXFXXXXA, 4000 amp, 600 volt AC, three pole. With Micrologic 6.0 amp trip unit, LSIG functions, ground fault, 3200 amp rating plug, key interlock, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1931
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Merlin Gerin MasterPact MP40H1 Circuit Breaker 4000A 600 VAC M/O D/O
Merlin Gerin MasterPact MP40H1 Circuit Breaker; 4000 amp, 600 volt AC, 3 pole. With STR 38 S trip unit, LSI functions, 4000 amp rating plug cat# 54770, shunt trip, closing release, motor & charged switch, auxiliary switch, LT alarm, overcurrent trip switch, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1962
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Merlin Gerin MasterPact MP40H1 Circuit Breaker 4000A 600 VAC M/O D/O
Merlin Gerin MasterPact MP40H1 Circuit Breaker; 4000 amp, 600 volt AC, 3 pole. With STR 38 S trip unit, LSI functions, 4000 amp rating plug cat# 54770, shunt trip, closing release, motor & charged switch, auxiliary switch, LT alarm, overcurrent trip switch, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1963
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Merlin Gerin MasterPact MP40H1 Circuit Breaker 4000A 600 VAC M/O D/O
Merlin Gerin MasterPact MP40H1 Circuit Breaker; 4000 amp, 600 volt AC, 3 pole. With STR 38 S trip unit, LSI functions, 4000 amp rating plug cat# 54770, shunt trip, closing release, motor & charged switch, auxiliary switch, LT alarm, overcurrent trip switch, manually operated (M/O), draw-out (D/O), used tested with report.
SKU: MCCB1964
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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 |
| B | 50A | 120V, 240V, 480V |
| C | 60A | 240V, 480V |
| C | 100A | 240V, 480V |
| D | 150A | 240V, 480V, 600V |
| D | 200A | 240V, 480V, 600V |
| E | 250A | 240V, 480V, 600V |
| E | 300A | 240V, 480V, 600V |
| F | 400A | 240V, 480V, 600V |
| F | 600A | 240V, 480V, 600V |
| G | 800A | 240V, 480V, 600V |
| G | 1200A | 240V, 480V, 600V |
| H | 1600A | 240V, 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.
