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EMA Electro Mechanics
Since its establishment in 1952, EMA has built more than 70 years of expertise in the electrical equipment industry. With manufacturing operations in Texas since 2009, EMA supplies high-voltage circuit breakers up to 345 kV, combining proven technology, U.S. manufacturing capabilities, competitive delivery times, and extensive experience in critical power applications.
PRODUCTS
HVCB 362 DT
The HVCB 362 DT is an outdoor dead-tank, SF₆-insulated high-voltage circuit breaker designed for extra-high-voltage transmission lines and critical substations. It features independent single-pole operation, providing maximum flexibility and reliability for demanding grid applications. The unit is rated at 362 kV, with a rated nominal current of 4,000 / 5,000 A, a rated short-time current of 50 / 63 kA for 3 seconds, and a rated peak current of 130 / 164 kA.
HVCB 245 DT
The HVCB 245 DT is an outdoor dead-tank, SF₆-insulated high-voltage circuit breaker designed for transmission lines, substations, and heavy industrial, mining, and AI applications. It features a robust three-pole operating mechanism for reliable performance in demanding environments. The unit is rated at 245 kV, with a rated nominal current of 4,000 A, a rated short-time current of 50 / 63 kA for 3 seconds, and a rated peak current of 130 / 164 kA.
HVCB 170 DT
The dead-tank high-voltage circuit breaker is an outdoor, SF₆-insulated solution designed for transmission lines, substations, and heavy industrial, mining, and AI applications. With the interrupter enclosed in a grounded tank, it provides enhanced safety, excellent switching performance, and high reliability under severe environmental conditions. The unit is rated at 170 kV, with a rated nominal current of 4,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
HVCB 145 DT
The dead-tank high-voltage circuit breaker is an outdoor, SF₆-insulated solution designed for transmission lines, substations, and heavy industrial, mining, and AI applications. With the interrupter enclosed in a grounded tank, it provides enhanced safety, excellent switching performance, and high reliability under severe environmental conditions. The unit is rated at 145 kV, with a rated nominal current of 4,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
HVCB 72 DT
The HVCB 72 dead-tank circuit breaker is an outdoor, SF₆-insulated solution designed for substations, power plants, data centers, and industrial facilities. With the interrupter enclosed in a grounded tank, it provides enhanced safety, excellent switching performance, and high reliability under severe environmental conditions. The unit is rated at 72.5 kV, with a rated nominal current of 4,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
VDH 72 / VDH 145
Following EMA’s vacuum technology evolution, the VDH 72 and VDH 145 are dead-tank, SF₆-free circuit breakers being developed to reduce environmental impact and help customers future-proof their fleets as regulations evolve. The units are designed for rated voltages of 72.5 / 145 kV, with a rated nominal current of 3,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
VEE 145
The VEE 145 is the vacuum evolution of EMA’s proven SF₆ circuit breaker, providing an SF₆-free solution designed to meet newly established European regulations while anticipating future requirements in the American market. It delivers proven performance and reliability at a rated voltage of 145 kV, with a rated nominal current of 3,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
HVCB 145 LT
The 145 kV Live Tank High-Voltage SF₆ Circuit Breaker integrates a double-end-break, air-break disconnect switch with the circuit breaker in a single unit. The group-operated disconnect switch uses three insulators and operates through rotation of the center insulator, combining switching and isolation functions to reduce substation footprint and installation complexity. The unit is rated at 145 kV, with a rated nominal current of 3,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
HVCB 145 LT
The 145 kV High-Voltage Live Tank Disconnecting Circuit Breaker combines compact live-tank construction with enhanced measurement capabilities through six integrated bar-type current transformers, each supporting up to three cores. This configuration provides measurement functionality comparable to a dead-tank circuit breaker while maintaining the compactness and modularity of a live-tank design. The unit is rated at 145 kV, with a rated nominal current of 3,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 108 kA.
HVCB 145 LT
The 145 kV High-Voltage Live-Tank Circuit Breaker combines the functions of a circuit breaker and disconnector in a single compact unit. It features an advanced double-motion system, in which both arc-breaking contacts move in opposite directions, increasing their relative separation speed for faster and more efficient arc extinction with reduced mechanical energy. The unit is rated at 145 kV, with a rated nominal current of 3,000 A, a rated short-time current of 40 kA for 3 seconds, and a rated peak current of 104 kA.
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