Medium Voltage Motor Control Center

The Medium Voltage Motor Control Center (MV MCC) houses centralized motor starters, control devices, and protection relays for medium voltage AC motors operating from 2.3kV to 15kV. Built on modular, compartmentalized metal-enclosed structures, it consolidates high-voltage motor circuits while isolating operational hazards.

Standard Busbar Rating: Up to 4000A

Short-Circuit Withstand: Up to 50kA for 3s

Enclosure Options: NEMA 1, NEMA 3R, IP41, IP54

Internal Arc Rating: IEEE 3c/Type 2B (Accessibility B)

Modular Compartmentalization: Physical metal barriers separate the busbar chamber, breaker/contactor compartment, and low-voltage control cabinet to prevent internal fault propagation.

Arc-Resistant Containment: Pressure-relief flaps and top-mounted exhaust plenums direct arc flash energy away from operators, satisfying IEEE C37.20.7 criteria.

Mechanical Interlocks: Interlock systems physically prevent racking the drawout vacuum contactor while the circuit is under load.

Thermal Monitoring: Integrated fiber-optic sensors continuously track temperature points at main busbar joints and cable terminations.

Oil & Gas: Main pipeline export pumps, gas injection compressors, and refinery raw water systems.

Mining & Minerals: High-torque grinding mills, slurry transport pumps, and underground ventilation fans.

Water & Wastewater: High-lift raw water pumps and large municipal booster stations.

Power Generation: Boiler feed pumps, forced draft fans, and scrubber circulation systems.

Assemblies are built directly to project Single-Line Diagrams (SLDs) and client technical specifications. Custom engineering options include:

Starter Types: Vacuum Contactor (FVNR/RVAT), Solid-State Soft Starters, or Medium Voltage Variable Frequency Drives (MV VFD).

Protection Relays: Integration compatibility with numerical protection relays from SEL, ABB, Schneider Electric, and Siemens.

Cable Entry: Configurable for top or bottom cable entry, or bus duct transitions.

Footprint Layouts: Back-to-back or front-access-only arrangements for space-restricted electrical rooms.

Cabinet frames are fabricated using CNC turret punches and laser cutting systems, maintaining structural dimensional tolerances within plus/minus 0.1 mm. Copper busbars undergo CNC bending, deburring, and silver plating at joint interfaces to restrict contact resistance.

Every assembly passes mandatory factory testing prior to release:

Dielectric Withstand Voltage Test: Power-frequency test applied across main and auxiliary circuits.

Main Circuit Resistance Measurement: Micro-ohm meter verification of busbar joints and contactor connections.

Mechanical Operation Test: Minimum 50 mechanical cycles of drawout mechanisms, safety shutters, and door interlocks.

Secondary Wiring Verification: Continuity and insulation resistance testing of all control logic circuits.

Standards Compliance: Engineered and type-tested in accordance with IEEE C37.20.3, IEEE C37.20.7, and IEC 62271-200.

Quality Management: Manufactured under ISO 9001:2015 certified operational processes.

Project Documentation Package Supplied:

General Arrangement (GA) and Floor Plan Drawings

Schematic and Wiring Diagrams

Bill of Materials (BOM) with component data sheets

Factory Acceptance Test (FAT) inspection reports and calibration certificates

Protection: Units are bolted to heavy-duty structural steel skids, sealed in moisture-barrier foil bags with proportional silica gel desiccant packs, and covered with heat-shrunk polyethylene shrouds.

Handling: Integrated lifting lugs and base channels are engineered for standard crane rigging and forklift transport.

Shipping Documentation: Packing lists, commercial invoices, and certificates of origin are enclosed in weatherproof exterior document holders.