ABB ef750-800 electronic overload relay 250a - 800a

Why Choose the ABB EF750-800 Electronic Overload Relay?

The ABB EF750-800 electronic overload relay is a heavy-duty motor protection device engineered to provide highly accurate protection against overload currents and phase failure in large industrial motor applications. Identified by part number 1SAX821001R1101, this relay forms part of the advanced ABB EF750 electronic overload relay series, designed for demanding industrial automation and high-power motor control systems.

The EF750-800 is a self-supplied electronic overload relay, meaning no additional external control power supply is required for operation. Compared with conventional thermal overload relays, it offers significantly improved protection precision, selectable trip classes and an extremely wide current adjustment range for enhanced flexibility in industrial motor starting applications.

With an adjustable current setting range of 250 to 800 A, integrated 1 NO + 1 NC auxiliary contacts, selectable trip classes 10E, 20E and 30E, and automatic or manual reset functionality, the EF750-800 delivers reliable motor protection while supporting direct mounting onto compatible ABB AF contactors for simplified installation and compact control panel layouts.

Key Advantages

• Reliable electronic overload and phase failure protection.
• 250–800 A adjustable current range.
• Self-powered operation with no external supply required.
• Selectable trip classes 10E, 20E and 30E.
• Integrated 1 NO + 1 NC auxiliary contacts.
• Automatic or manual reset selectable.
• High operational accuracy and temperature compensated protection.

Key Features

• ABB EF750 electronic overload relay series.
• 250–800 A setting range.
• 3-pole motor protection relay.
• Integrated phase failure sensitivity.
• Trip classes 10E, 20E and 30E selectable.
• Integrated 1 NC trip contact.
• Integrated 1 NO signal contact.
• STOP and TEST buttons integrated.
• Direct mounting onto ABB high-current contactors.
• ATEX and IECEx certified for applicable production versions.

Technical Specifications

• Manufacturer: ABB
• Series: EF750
• Model: EF750-800
• Part number: 1SAX821001R1101
• Product type: Electronic overload relay
• Current setting range: 250–800 A
• Rated operational current: 800 A
• Trip classes: 10E / 20E / 30E selectable
• Rated operational voltage: Main circuit 1000 V AC
• Auxiliary circuit voltage: 600 V AC/DC
• Rated insulation voltage: 1000 V
• Rated impulse withstand voltage: Main circuit 8 kV
• Number of poles: 3P
• Auxiliary contacts: 1 NC + 1 NO
• Connection type: Screw terminals
• Degree of protection: Housing IP20, terminals IP00
• Mounting type: Direct attachment to contactor
• Frequency: 50 / 60 Hz
• Operating temperature: approx. -25 °C to +70 °C
• Standards: IEC/EN 60947-4-1, UL 60947-4-1
• Dimensions (W × H × D): approx. 244 × 111.6 × 187.73 mm
• Weight: approx. 2.765 kg

Advanced Electronic Motor Protection

Electronic overload relays continuously monitor motor current and react rapidly to overload or phase loss conditions, helping prevent overheating, insulation damage and unexpected downtime. Compared with traditional thermal overload relays, electronic overload relays provide greater accuracy, improved flexibility and selectable trip characteristics for different motor starting requirements.

The ABB EF750 series is widely used in industrial automation, motor control centres and heavy-duty machinery applications where accurate motor protection, dependable operation and flexible configuration are essential for efficient industrial performance.

Typical Applications

• Industrial motor starters and control panels.
• Heavy-duty pumps and compressors.
• Conveyor and material handling systems.
• Industrial process control applications.
• OEM machinery and automation systems.
• Mining and heavy industrial installations.

Trusted by Industrial Automation Engineers

ABB EF electronic overload relays are trusted worldwide for accurate motor protection, flexible trip settings and dependable performance in industrial automation and heavy-duty machinery applications.