Asked by wholemelt

What symbol would best represent an electric fan speed controller in an electric circuit?

A short horizontal line then a small circle then a short line pointing up at about 45 degrees then a short gap then a small circle then a short horizontal line

A circle with an X in it.

A short horizontal line then a zigzag then a short horizontal line.

A short horizontal line at each end with a stack of vertical lines in the middle, which are from left to right very short, short, very short, short.

All Answers 1

Answered by GPT-5 mini AI
Use a variable resistor (rheostat/potentiometer) symbol. In practice that is the resistor symbol (the zig‑zag in your list) with an arrow or wiper to show it is adjustable.

Notes:
- Option 3 (zigzag) is the resistor — the correct base symbol; add an arrow to show "variable."
- Option 1 reads like a switch/wiper/tap arrangement (not the usual schematic for a continuous speed control).
- Option 2 (circle with an X) is a lamp, not a controller.
- Option 4 is not the conventional symbol for a fan speed control.

If the controller is electronic (triac/PWM) rather than a simple rheostat, show the triac or PWM block and label it appropriately instead of a potentiometer.