DC Isolator Switch vs AC Isolator Switch: the difference

10th Nov 2023

Electric systems require maintenance and repair work from time to time. To ensure safety and efficiency during such work, it is essential to isolate an electrical device or section of an electric circuit from the rest of the system and stop the flow of current. This is where isolator switches come in handy. There are two main types of isolator switches: DC and AC. Understanding their differences is crucial to selecting the appropriate isolator switch for your system.

DC Isolator Switch: Designed for Fluctuating Current

DC isolator switches are designed to handle fluctuating currents where both magnitude and direction change. They have a slower switching speed compared to AC isolator switches. DC isolator switches are suitable for high-voltage electrical equipment like solar panels, batteries, and electric vehicles.

AC Isolator Switch: Designed for Constant Current

AC isolator switches are designed to handle constant current or current that flows in one direction. They have a higher voltage rating than DC isolator switches, making them suitable for homes or businesses.

Key Differences Between DC and AC Isolator Switches

  1. Type of Power Used: DC isolator switches are used for direct current, while AC isolator switches are used for alternating current.
  • Power Capacity: AC isolator switches can handle higher voltage levels and normal AC current levels, while DC isolator switches can handle higher current levels and a constant voltage level.
  • Wiring Configuration: DC isolator switches have a simpler wiring configuration, with fewer poles and often with only two main conductive contacts. This is to accommodate the direct and continuous flow of current in DC circuits. AC isolator switches have more complicated wirings with at least three poles designed to interrupt all phases of the alternating current simultaneously for safety purposes.
  • Switching Speed: AC isolator switches are designed to handle the frequently changing direction of current in AC systems, resulting in faster switching speed. DC isolator switches, on the other hand, are made to handle a constant flow of current, so they generally have a slower switching speed.

It is crucial to choose the appropriate isolator switch for specific electrical systems to avoid damaging the electrical system or causing a fire.

 The TOSUNlux DC Isolating Switch (S32D S32D-T S32D-TL S32D-W1 S32D-W2) would be an excellent choice as it has a safe lead among similar products.

Meanwhile, AC isolator switches are meant for homes and businesses.

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