ABB TF42-0.41 Thermal Overload Relay

ABB TF42-0.41 Thermal Overload Relay is a three-pole, bimetallic overload protection device designed for low-voltage motor circuits. It provides adjustable thermal protection with a per-pole full-load current rating of 0.41 A and a thermal setting range of 0.31–0.41 A, allowing precise tailoring to small three-phase motors. The relay is intended to be used as part of ABB motor starter assemblies with contactors, and it coordinates with protective devices rated up to 100 kA SCCR at system voltages up to 480/600 V AC. Each pole has a resistance of 11,421.77 mΩ (about 11.42 Ω), with power loss per pole ranging from 1.1 W at the lower setting to 1.9 W at the upper setting. The TF42-0.41 supports compatible protection schemes such as 30 A Class J fuses and follows standard coordination practices for type 2 protection. This model provides reliable, trip-optimal protection for modest-capacity motors, helping prevent overheating and electrical faults while fitting neatly in ABB’s line of motor protection accessories.