Contactors for Industrial Applications
Power contactors are the backbone of switching equipment at any industrial facility. They provide reliable switching of electrical circuits under load, operating for millions of cycles without degradation. The Chastotnik.ua catalog features contactors from leading global manufacturers: ABB, Schneider Electric, LS Electric, and other industrial automation brands.
What Is a Contactor and Where Is It Used
A contactor is an electromagnetic switching device designed for frequent switching of power electrical circuits under load. Unlike a circuit breaker, a contactor is rated for high-frequency operation — up to several thousand cycles per hour.
Key application areas for contactors:
- Motor control — starting, stopping, and reversing induction motors in industrial drives, conveyor systems, and pumping stations
- HVAC systems — switching compressors, fans, and heaters in heating, ventilation, and air conditioning systems
- Pumping equipment — controlling centrifugal and submersible pumps, borehole equipment
- Lighting systems — switching high-power lighting groups in production halls, warehouses, and stadiums
- Capacitor banks — switching capacitor batteries for reactive power compensation
- Heating equipment — switching electric furnaces, drying chambers, and industrial heaters
How to Choose a Contactor
Proper contactor selection determines the reliability and longevity of your electrical system. Key selection parameters:
Rated current and utilization category. Contactors are classified by categories: AC-1 (resistive or slightly inductive load), AC-3 (motor starting and stopping), and AC-4 (reversing and braking). For motors, always select a contactor rated for AC-3 with a 20–30% current margin.
Coil voltage. The coil supply voltage must match the control circuit: 24V AC/DC for PLC-based systems, 110V for industrial panels, 220V (most common) for general industrial applications, 380V for direct connection to the power network.
Number of poles. 3-pole contactors are the standard for three-phase motors. 4-pole contactors are used for switching three-phase circuits with neutral or in single-phase systems requiring double-break disconnection.
Auxiliary contacts. Most contactors feature front-mounted and side-mounted auxiliary contacts (NO — normally open, NC — normally closed). These are essential for signaling circuits, interlocking, and self-holding schemes.
Mounting. Modern contactors mount on 35 mm DIN rail, enabling fast installation in distribution boards and control cabinets.
Popular Contactor Brands
The Chastotnik.ua catalog features contactors from manufacturers with decades of experience in industrial switching:
ABB — the A-line series (A9…A300) for general industrial use and the AF series with electronic coil for wide voltage range operation. ABB contactors stand out for their compact dimensions and high reliability under intensive operation.
Schneider Electric — TeSys D and TeSys K ranges for different power levels. TeSys D is the industrial standard for motors up to 75 kW; TeSys K is a compact solution for light-duty applications up to 5.5 kW.
LS Electric — the MC series (MC-9a…MC-800a) covering a wide range of rated currents. LS contactors offer an optimal price-to-reliability ratio for industrial facilities.
Contactors for Use with Variable Frequency Drives
Contactors are frequently used alongside variable frequency drives (VFDs) in two primary configurations:
Input contactor (before the VFD). Installed between the circuit breaker and the VFD input. Provides safe power disconnection during emergencies or on command from the safety system. Mandatory in schemes requiring functional safety compliance (STO, SIL).
Bypass scheme (bypass contactor). Allows switching the motor to direct mains power if the VFD fails. Critically important for continuous processes — pumping stations, ventilation systems, and conveyor lines.
Important: installing a contactor on the VFD output for switching under load is not recommended — it may damage the inverter's output IGBT transistors. If output-side switching is required, the contactor must operate only at zero frequency with the motor stopped.
Why Buy from Chastotnik.ua
- Genuine equipment — we work directly with authorized distributors of ABB, Schneider Electric, and LS Electric
- Technical consultation — we help select the right contactor for your specific application, considering load category and control scheme
- Complete supply — contactors, soft starters, variable frequency drives, sensors, and auxiliary equipment from a single supplier
- Fast delivery — popular ratings from stock; custom orders from 5 business days
- Manufacturer warranty — official warranty on all contactors with full documentation package
