Overview
The ABB T25 DU 9054 2.2-3.1 thermal overload relay is a compact, three-pole protection device designed to safeguard electric motors and circuits from sustained overload conditions. This relay uses bimetallic heating elements to detect abnormal current flow and automatically trip the control circuit, preventing equipment damage and downtime. Built to meet EN 60947 and IEC 947 standards with a trip class of 10A and voltage rating of 660/690V, it is widely used in motor starter circuits and industrial control panels.
Key Features
- Temperature compensation, trip contact (NC), signal contact (NO), automatic or manual reset selectable, trip-free mechanism, STOP and Test function with trip indication
- Two built-in auxiliary contacts: NC (marked 95-96) and NO (marked 97-98), physically separate for use in control and indication circuits
- Adjustable current setting range: 2.2–3.1 amperes
- Phase failure protection according to IEC 947-4-1 for improved motor protection in case of single-phase operation
- Compact DIN-rail or contactor-mount form factor suitable for retrofit applications
Technical Specifications
The relay provides precise motor protection through bimetals (one per phase) that are indirectly heated by motor current and respond to both sustained overloads and phase failures. The tripping class indicates the maximum tripping time in seconds under IEC 947-4-1 specified test conditions at 7.2 times the setting current. All models feature dual auxiliary contacts for signaling and control logic integration.
Typical Applications
- Three-phase motor protection in industrial control panels
- Retrofit replacement in existing contactor-based starter circuits
- Protection of single-speed motors in manufacturing and process equipment
- Compliance with IEC 947-4-1 and EN 60947 safety standards
- Integration with alarm and notification circuits via auxiliary contacts
Compatibility & Replacements
The ABB T25 DU series is compatible with ABB low-voltage contactors and motor starters, including the AL9 and A contactor families. Used T25 DU units are in-stock for drop-in replacement of worn or damaged relays. When specifying a replacement, verify the amperage setting (2.2–3.1A on this unit) matches the motor’s full-load current. Consult ABB control relay datasheets or your system integrator to confirm compatibility with your existing panel layout and reset preference (manual or automatic). This unit is in good used condition and ready for installation.
