🔍 Key Concepts

• Thermal overload relays and how they respond to ambient temperature changes • Purpose of the full-load ampere (FLA) adjustment range shown in figure A (+/- 15% of FLA) • Difference between preventing nuisance trips and providing better motor protection

💭 Think About

• When the ambient temperature around a thermal overload relay gets HIGHER, does the bimetal element trip at a lower or higher motor current? How does that affect nuisance tripping? • If the relay is calibrated at a standard temperature, why would you ever need to set the trip point ABOVE the motor nameplate full‑load current? What operating condition would that compensate for? • Looking at figure A, think about whether the +/- 15% adjustment is primarily to increase, decrease, or fine‑tune the trip point relative to motor FLA when conditions differ from the nameplate rating.

✅ Before You Answer

• Be clear on whether high ambient temperature makes the relay MORE or LESS sensitive to current before adjustment. • Check which choice correctly pairs raising the trip value with the correct ambient condition and the correct purpose (nuisance trips vs better protection). • Eliminate any option that suggests changing the trip setting in a direction that would make the overload relay more likely to trip when the ambient is already making it more sensitive, if the goal is to avoid nuisance trips.