ABB tf42-38 thermal overload relay 35a - 38a

Why Choose the ABB TF42-38 Thermal Overload Relay?

The ABB TF42-38 Thermal Overload Relay with product code 1SAZ721201R1055 is a high-performance motor protection relay designed to provide reliable overload and phase failure protection for industrial three-phase motors. As part of the trusted ABB TF42 thermal overload relay series, this electromechanical protection device is engineered for direct mounting onto ABB AF series contactors in motor starter assemblies.

The TF42-38 delivers dependable overload protection while helping improve operational safety and reduce unplanned downtime. Integrated temperature compensation, selectable manual or automatic reset, trip indication, STOP functionality and built-in auxiliary contacts simplify diagnostics and maintenance within industrial control systems.

With an adjustable current range of 35 to 38 A, compact dimensions and direct mounting capability, the ABB TF42-38 is ideal for protecting industrial motors used in compressors, conveyors, pumps, ventilation systems, material handling equipment and OEM automation machinery.

Key Advantages

• Reliable thermal overload protection for industrial motors.
• Adjustable current range from 35 to 38 A.
• Integrated phase failure sensitivity for enhanced motor protection.
• Compact design for direct mounting onto ABB AF contactors.
• Trip class 10 protection for standard motor applications.
• Selectable manual or automatic reset functionality.
• Integrated STOP function and visual trip indication.

Key Features

• ABB TF42 thermal overload relay series.
• 35 to 38 A adjustable overload setting.
• Trip class 10 overload protection.
• 3-pole motor protection relay.
• 1 NO + 1 NC integrated auxiliary contacts.
• Temperature-compensated operation.
• Manual or automatic reset selection.
• Trip-free mechanism with STOP function.
• Compact IP20 enclosure for industrial control panels.
• Suitable for direct connection to ABB AF09 to AF38 contactors.

Technical Specifications

• Manufacturer: ABB
• Series: TF42 Thermal Overload Relays
• Model: TF42-38
• Product code: 1SAZ721201R1055
• Product type: Thermal overload relay
• Current adjustment range: 35 to 38 A
• Rated operational current: 38 A
• Trip class: Class 10
• Number of poles: 3
• Auxiliary contacts: 1 NO + 1 NC
• Rated insulation voltage: 690 V AC
• Rated operational voltage: Auxiliary circuit 600 V AC/DC
• Rated impulse withstand voltage: 6 kV
• Protection rating: IP20
• Reset method: Automatic or manual
• Mounting type: Direct attachment to contactor
• Terminal type: Screw terminals
• Dimensions (H × W × D): approx. 88.3 × 45 × 70.5 mm
• Weight: approx. 0.145 kg
• Operating temperature: approx. -25 °C to +60 °C
• Standards: IEC/EN 60947-1, IEC/EN 60947-4-1, UL 60947-4-1

Reliable Motor Protection for Industrial Automation

Thermal overload relays are critical components in industrial motor control systems, helping protect motors against overheating caused by excessive current draw, stalled rotor conditions or phase imbalance. By disconnecting the motor during overload events, overload relays reduce maintenance costs and improve operational reliability.

The ABB TF42 series is specifically designed for machine builders and industrial automation engineers requiring dependable motor protection, compact installation and seamless integration with ABB contactor systems. Its direct mounting capability and integrated auxiliary contacts simplify wiring and panel assembly.

Typical Applications

• Industrial motor starter assemblies.
• HVAC and ventilation systems.
• Pumps and compressor protection.
• Conveyor and material handling equipment.
• Packaging and OEM machinery.
• Industrial automation control panels.

Trusted by Industrial Engineers Worldwide

ABB thermal overload relays are trusted worldwide for delivering dependable motor protection, long operational life and reliable integration into industrial automation systems.