In industrial and commercial power systems, the importance of electricity is second to none. This being the case, the risks associated with handling electric power also rank above those involved in many other types of work. To sum it up, power must be distributed in a manner both safe and reliable. A device called a contactor helps keep it safe and right by switching the load on and off as conditions may demand.
What is a Contactor?
A contactor is in effect a small relay having an important part to play in the switching of an electrical power circuit. The electro magnet coil usually controls its action.
In power distribution, a contactor plays the same general part as in lighting and home power work, permitting motors, lights, and other loads to be power system, it’s critical that no personnel come in contact with live wires, as this can cause fatal accidents. Proper isolation will reduce the risk of shock and other dangers. This is ensured by contactors, such as circuit selectors, which open the circuit if someone opens the wrong switch.

Decreasing the Chance of Fire
Electrical fires are a possibility with all power systems in general, but are of great concern in industrial settings where a large amount of power is used. In case of a short circuit, faulty wiring, etc., contactors will cut the line from risk of overheating. They are thus indispensable to both power and fire department officials as an adjunct to their perfect duty in heavy-duty circuits.

Increasing the Reliability of the Power System
Modern power systems depend on reliable contactor systems to prove the circuits live only when in use. This saves not only power but unnecessary wear and tear on the components of the power system. In case of overload or other electrical fault, the contactor will trip and keep the rest of the system in use.
Providing Specialized Protection to Sensitive Equipment
Special great care has to be used when dealing with power inverters, photovoltaic and other sensitive equipment. They require special protection from damage by power surges and other faults. A contactor will automatically cut the circuit and protect the sensitive equipment in case of irregular conditions developing.Increasing Fault Detection and Response Time
“Quick draw contactors” come with features such as fault detection and enable the contactor to detect a system fault and disconnect the problematic circuit within a fraction of a second, thus minimizing the chance of widespread damage and keeping damaged circuits from causing havoc throughout the rest of the system.
Where We Use Contactors
Contactors are ubiquitous from small residential applications through heavy industrial machines. Some applications include the following:
Motor Control: Contactors are widely used in motor control circuits and throughout electrical motors to provide sensible switching-based protection.
HVAC Applications: In HVAC applications contactors control electrical fans, compressers, and pumps to ensure that they never lose power due to an electrical hiccup.
Power Inverters & Solar: In renewable power applications the “solar array contactor” creates switching between the solar array and the inverter, and maintains a clean safe connection to the grid.
Battery Energy Storage Systems: Contactors are heavily utilized for switching power to and from the batteries
Choosing The Right Contactors
When it comes to choosing contactors for your power distributing system several factors will come into play:
Current/Voltage Ratings: Make sure that the chosen contactor has a compelling current carrying capability versus what you actually plan on running through it. Too low a rating and you’ll wind up with smoke in the controller.
Manual, Semi-Automatic, Fully Potential-Controlled: Choose the level of human control you want for the system, whether a manual “click or don’t click” and emergency shutoff, semi streamlined, or a fully computerized potential controlled version.
High Quality: Look for traditional, good, deep-rooted brands to ensure quality operation for your high-maintenance rig.
Safety: Look for contactors with some built-in thermal overload protection, fault detection, etc.
Conclusion
Contactor systems are a vital piece of the electrical safety and correct operation puzzle. Used throughout our power distribution systems the role they play in regulating, isolating, and protecting sensitive equipment and preventing overload and fault cascades means we may not even know we had a problem. Electricity did not kill thousands of people and destroy millions of dollars of equipment this year because of remediative techniques like this one. I hope you’ll decide that a good known, solid contactor would be a worthwhile piece of equipment to add to your power distribution system.