RFN420420 - T/O RELAY 250-420A MAN-AUTO

Why Choose the RFN420420?

Designed for robust motor protection, the Lovato RFN420420 thermal overload relay safeguards three-phase circuits with dependable performance. The RFN420420 features a 250…420 A operational current range, a three-pole configuration, and selectable manual or automatic reset. As a non phase failure / non single-phase sensitive type, it provides application-specific protection where single-phase sensitivity is not required, pairing seamlessly with Lovato B-series contactors.

Engineered for panel integration via screw mounting, this relay offers IP20 frontal protection and a rated insulation voltage Ui of 1000 V. It operates from −25 to 60 °C, with storage down to −50 °C and use up to 3000 m altitude. Conforming to IEC/EN 60947-1 and 60947-4-1 plus UL508 and CSA C22.2 n° 14, it ensures compliance across global installations.

Key Benefits

• Wide 250–420 A range supports high-current motor protection.
• Three-pole design suited to three-phase circuits and starters.
• Manual or automatic reset for flexible maintenance strategies.
• Non phase failure / non single-phase sensitive type for specific needs.
• IP20 frontal protection enhances operator safety during access.
• Screw mounting simplifies secure panel installation.
• Certified to IEC/EN 60947, UL508 and CSA for compliance.

Technical Specification

• Number of poles: 3
• Pollution degree: 3
• IP degree (frontal): IP20
• Rated insulation voltage Ui (IEC/EN): 1000 V
• Terminal tightening torque: 35 to 35 Nm
• Ith (IEC): 10 A
• Operating temperature: -25 to 60 °C
• Storage temperature: -50 to 70 °C
• Max altitude: 3000 m
• Weight: 2460 g

What’s Included

• Lovato RFN420420 thermal overload relay
• Manufacturer documentation and instructions

Applications

• Overload protection for three-phase motors rated 250–420 A
• Integration with Lovato B-series contactors in motor starters
• Industrial control panels requiring IEC/EN 60947 conformity
• Installations needing manual or automatic reset options

Safety note: Installation and settings must be performed by qualified personnel. Adhere to the specified current range, environmental limits and IP20 frontal rating, and tighten terminals to 35 to 35 Nm. Isolate power before servicing.