What is O.L?

• A. Over Level
• B. Overload, used to protect components from over current situations
• C. Open Loop
• D. Ohm Load

Answer: (B)

O.L. stands for overload. It is the indicator shown when a measurement or signal exceeds the instrument’s available range or limits, so the device cannot display a meaningful value. In practice, you’ll see this on a digital meter when the input is too large for the selected range, meaning you should switch to a higher range or reduce the signal to get a valid reading. This concept is tied to protection: when current or signals run too high, protective mechanisms (like fuses or circuit breakers) act to prevent damage, and the overload indication is a cue that the system is at or beyond safe operating limits. The other terms don’t fit standard instrumentation usage—over level, open loop, or ohm load aren’t the recognized meanings for O.L. in this context.