ABB TF42-5.7 Thermal Overload Relay

ABB TF42-5.7 Thermal Overload Relay is a three‑pole motor protection device intended for inclusion with ABB TF-series contactors to provide economical electromechanical overload protection in the main circuit. The per‑pole current setting for TF42‑5.7 covers 4.20 to 5.70 A, with a nominal value aligned to 5.70 A, enabling precise protection for motors in the lower‑to‑medium current range. Electrical parameters listed for TF42‑5.7 include a per‑pole resistance of 59.10 mΩ and a per‑pole power loss of 1.0–1.9 W across the setting range, reflecting the relay’s low energy consumption during operation. The device is specified for short‑circuit protection device coordination Type 2 with a 20 A rating and uses a Type gG path for fault current. As part of ABB’s TF42 family, this relay is designed for use in low‑voltage motor circuits to protect against overload while coordinating with compatible protection components within the ABB motor protection ecosystem. Typical applications include motor starters and control gear in industrial automation, HVAC, pumps, conveyors, and other machinery where reliable, component‑level overload protection is required.