What voltage is used on the power control side?

What voltage is used on the power control side?

• A. 240v
• B. 120v
• C. 24v
• D. 12v

Answer: (C)

Control circuits are kept at a low voltage so they’re safe to work with while still reliably powering relays, contactors, and sensors. In many systems the power side operates at higher line voltages to drive motors, heaters, or other loads, and a transformer steps that down to a standard control voltage. The typical control voltage is 24 volts, usually 24 VAC, which is high enough to drive relays and solenoids but low enough to reduce shock risk and allow smaller wiring and simpler protection. Other voltages listed would either be unnecessarily hazardous for routine control work or are less common for general control circuits, making 24 volts the practical and widely used choice.

Control circuits are kept at a low voltage so they’re safe to work with while still reliably powering relays, contactors, and sensors. In many systems the power side operates at higher line voltages to drive motors, heaters, or other loads, and a transformer steps that down to a standard control voltage. The typical control voltage is 24 volts, usually 24 VAC, which is high enough to drive relays and solenoids but low enough to reduce shock risk and allow smaller wiring and simpler protection. Other voltages listed would either be unnecessarily hazardous for routine control work or are less common for general control circuits, making 24 volts the practical and widely used choice.