How Does a Fused Disconnect Switch Differ from a Circuit Breaker?

When an electrical circuit carries more current than it was designed to handle, significant problems can occur. Sensitive equipment like electronics, lighting, or motors can be damaged or destroyed, and the extra current can generate heat in wires that are undersized for the load, possibly resulting in a fire. Overcurrent protective devices, such as fused disconnect switches or circuit breakers, are designed to open or disconnect the circuit when an overload or short-circuit occurs, limiting damage to connected equipment and preventing fires. In many cases, fused disconnect switches and circuit breakers can be used interchangeably, but in some applications, only one will be the best choice for the situation.

At PSI Control Solutions, we offer both fused disconnect switches and circuit breakers, and our specialists can work with your facility to determine the best solutions for your needs. Located in Charlotte, NC, we have been providing quality electrical products and services to a variety of commercial and industrial clients since 1961.

Does your business need safety switches, disconnects, or circuit breakers for heavy-duty commercial or industrial applications? Contact PSI Control Solutions today at 704-594-4107!

What’s the Difference?

Fused disconnect switches and circuit breakers are both intended to open a circuit quickly in the event of a current overload or a short-circuit. Their designs vary greatly however, and they may be used under slightly different circumstances, depending on the needs of your facility.

A fused disconnect switch is a combination of a switch to disconnect the circuit and a fuse to shut the circuit off in the event of a problem. When installing or maintaining equipment on the circuit, or the circuit itself, the switch provides a method to manually shut off the power. The fuse incorporates a small filament that is matched to the current rating of the circuit. If the amperage on the circuit exceeds the fuse’s rating for a long enough time, the filament will melt, disconnecting the circuit automatically and permanently. To restore power, the fuse must be replaced. Fuses are available in multiple sizes and ratings. Standard fuses can react quickly to overcurrent situations, breaking the circuit almost immediately, while slow-burning fuses can handle high currents for short intervals, which can be useful to handle the in-rush current of motors when they first start.

A circuit breaker combines the functions of a switch and an overcurrent disconnect into one device. When maintenance needs to be performed on the circuit or connected equipment, the circuit breaker can be manually turned off. When a short-circuit or an overload is detected, an electromagnet turns the circuit breaker off automatically. To restore power once the fault has been corrected, the circuit breaker needs only to be turned back on.

Which Is the Best Solution for Your Application?

Fused disconnect switches are often used in circuits that have extremely high currents, with the fuse guaranteeing that the circuit will be disconnected if there is a problem. Circuit breakers provide a convenient alternative, with no fuses to be replaced, and modern breakers can typically be used for the same applications as fuses, except in certain high-current situations. For three-phase circuits, circuit breakers may provide a more simple solution than fused disconnect switches. A qualified electrician can help you determine the best choices for your facility and equipment.

Disconnects and Circuit Breakers from PSI Control Solutions

At PSI Control Solutions, we can help you provide a safe, productive work environment with products like circuit breakers, disconnects, safety switches, and more!

Contact us today at 704-594-4107 or browse our product guide for more information!