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RF380040 – T/O RELAY 0 25-0 4A
Lovato RF380040 is a three-pole 0.25–0.40 A trip class 10A thermal overload relay with phase-failure sensitivity for direct mounting on BF09–BF38 contactors.
£39.96
Why Choose the Lovato RF380040 Thermal Overload Relay?
The Lovato RF380040 is a three-pole thermal overload relay designed to protect three-phase motors against sustained overloads and phase failure. Part of the Lovato Electric RF38 series, it mounts directly onto compatible BF09–BF38 contactors for a compact motor-control assembly.
Its adjustable 0.25–0.40 A current range enables the relay to be matched to the protected motor’s rated current. The trip class 10A thermal release provides dependable overload protection, while phase-failure sensitivity helps protect motors when one supply phase is lost.
The RF380040 supports manual or automatic resetting and includes a test button, trip indicator and 1NO + 1NC auxiliary contacts. Its front face is rated IP20, and the relay is suitable for operational frequencies from 0–400 Hz.
Key Advantages
- Adjustable 0.25–0.40 A motor protection range.
- Phase-failure and single-phase sensitivity for enhanced motor protection.
- Direct mounting onto Lovato BF09–BF38 contactors.
- Selectable manual or automatic reset operation.
- Integrated test button and visible trip indication.
- 1NO + 1NC auxiliary contacts for signalling and control circuits.
Key Features
- Lovato Electric RF38 series thermal overload relay.
- Three-pole thermal release for three-phase motors.
- 0.25–0.40 A adjustable current setting.
- Trip class 10A.
- Phase-failure and single-phase sensitive operation.
- Manual or automatic reset selection.
- Built-in test button and trip indicator.
- Direct mounting on BF09–BF38 contactors.
- Front protection rating of IP20.
Reliable Thermal Protection for Three-Phase Motors
Thermal overload relays monitor the current drawn by a motor and interrupt its contactor control circuit when a sustained overload is detected. Correctly setting the RF380040 within its 0.25–0.40 A range helps protect motor windings against excessive heating and premature failure.
The relay’s phase-failure sensitivity provides additional protection where loss of one phase could cause damaging current imbalance. As an overload relay does not provide short-circuit protection, it must be used with suitable upstream fuses or another appropriate short-circuit protective device.
Typical Applications
- Protection of low-current three-phase motors.
- Motor starters using Lovato BF09–BF38 contactors.
- Industrial pumps, fans and ventilation equipment.
- Conveyors and material-handling machinery.
- Packaging and production equipment.
- Industrial control panels and automation systems.
Technical Specifications
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| Current Range | 0.25–0.4 A | |
|---|---|---|
| Compatible With | BF09–BF38 | |
| Device Type | Thermal Overload Relay | |
| Load Voltage | 690 V | |
| Monitored Supply | Single-phase | |
| Reset Type | Manual or automatic | |
| Contacts | 1NO + 1NC | |
| IP Rating | IP20 | |
| HS Code | 85364900 | |
| Manufacturer | Lovato Electric | |
| Series | RF38 | |
| Model | RF380040 | |
| Product type | Thermal overload relay | |
| Number of poles | 3 | |
| Current adjustment range | 0.25–0.40 A | |
| Trip class | 10A | |
| Phase-failure sensitivity | Yes | |
| Reset type | Manual or automatic | |
| Auxiliary contacts | 1NO + 1NC | |
| Auxiliary contact conventional thermal current | 10 A | |
| Auxiliary contact designation | B600-R300 | |
| Rated operational voltage | 690 V | |
| Rated insulation voltage | 690 V | |
| Rated impulse withstand voltage | 6 kV | |
| Operational frequency | 0–400 Hz | |
| Protection rating | IP20 frontal | |
| Mounting type | Direct mounting on BF09–BF38 contactors | |
| Overvoltage category | III | |
| Pollution degree | 3 | |
| Operating temperature | -25 to +60 °C | |
| Storage temperature | -50 to +70 °C | |
| Temperature compensation range | -20 to +60 °C | |
| Maximum operating altitude | 3000 m | |
| Weight | 158 g |
Frequently Asked Questions
What is the Lovato RF380040 used for?
The RF380040 protects three-phase motors against sustained overloads and phase failure when installed with a compatible Lovato BF09–BF38 contactor.
What is the adjustable current range of the RF380040?
The relay has an adjustable current setting range of 0.25–0.40 A.
Which contactors are compatible with this overload relay?
The RF380040 is designed for direct mounting on Lovato BF09–BF38 contactors.
Can the RF380040 be reset automatically?
Yes. The relay can be configured for either manual or automatic resetting.
Does the RF380040 provide short-circuit protection?
No. It provides thermal overload and phase-failure protection, so suitable upstream short-circuit protection must also be installed.
Trusted Motor Protection from Lovato Electric
Lovato Electric RF38 thermal overload relays provide dependable motor protection, convenient contactor mounting and practical control features for industrial motor starters and automation panels.
