DC Contactors

At SMP Trombetta, we are an industry-leading designer and manufacturer of DC power switching and power management products. We offer an extensive range of electro-mechanical and electronic components suitable for use in mobile equipment, including robust and reliable DC contactors.

A DC contactor is an electro-mechanical device that switches high currents in direct current (DC) circuits. When carefully designed, selected, and installed with regard to environmental and operating conditions, they can be used in a variety of applications, including in the following industries: agriculture, automotive, construction, lawn and garden, marine, mobile hydraulics, and trucking.

Below we outline the basic operating principles of DC contactors and the product solutions we have available.

A Basic Overview of DC Contactors

DC contactors switch current in high current DC circuits. Their basic design consists of the following components: a coil, a plunger, and contacts.

At rest, a DC contactor is (generally) normally open. When power is applied to the coil, an electromagnet is created. When the coil is energized, the electromagnet field pulls the plunger into the coil and forces the contacts to close, completing the load circuit. When the contacts close, current is allowed to flow into the connected equipment. When power to the coil is interrupted, the electromagnet de-energizes, the magnetic field dissipates, and the contacts spring apart, reopening the circuit and ceasing power flow to the load.

These components facilitate the quick closing and opening of a circuit—i.e., turning a piece of equipment on and off. While they operate similarly to relays, they’re better suited for high-current applications than low-current applications, such as heavy-duty heating, lighting, motor, and energy storage systems.

Industrial DC Contactors From SMP Trombetta

Our DC contactors are designed and constructed to be robust and cost-effective. They accommodate current switching up to 48 VDC and, depending on the exact model, in-rush capacities up to 1000 A and continuous carry capacities up to 250 A. Typical applications for our DC contactors include vehicle battery systems in agricultural, construction, heavy trucking, lawn and garden, and marine equipment.

While we offer a broad selection of standard DC contactor designs, all of them can be customized to meet a customer’s exact specifications, including coil operation and mounting bracket configuration. They can be used as components in new systems or as OEM replacement parts in existing systems.

For additional information about DC contactors, check out our blog post, “What Are DC Contactors?”. For pricing or other details about one of our products, contact us today, and view our Product Families above.