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Solaronics Thermal Overload Relay for Electric Motors (RW27-1D3-U004)
The Thermal Overload Relay (RW27-1D3-U004) is a robust protection device specifically engineered for electric motors. This 3-pole relay provides essential safeguarding against damaging conditions such as overloads and phase loss, which can lead to motor overheating and failure. When an overload or phase loss occurs, the motor current increases, triggering the relay's tripping mechanism. This mechanism actuates the auxiliary contacts (95-96 NC and 97-98 NO), which then disconnect the load via a contactor, protecting the motor. The disconnection time is precisely managed by the relay's tripping curve, which is related to the overload current and the current set on the relay. After a trip, the relay can be manually or automatically reset once the system has reestablished.
This particular model, RW27-1D3-U004, has a current range of 2.8 to 4 Amperes and operates with a tripping thermal class 10, indicating standard trip times for general motor protection. It is designed for direct mounting to compatible contactors, specifically the CWM9-40 model, without requiring additional accessories. It is also suitable for use with both AC and DC loads.
Key technical specifications include a rated insulation voltage (Ui) of 690 V (IEC) / 600 V (UL) and a rated impulse withstand voltage (Uimp) of 6 kV. The relay can operate at a frequency of 25 to 400 Hz with a maximum operating frequency of 15 operations per hour. Its main terminals offer an IP10 degree of protection, while the auxiliary terminals are rated IP20 (conforming to IEC 60529).
The auxiliary contacts have a rated thermal current (Ith) of 6A at 55°C and various rated operational currents (Ie) for AC-14/AC-15 and DC-13/14 applications across different voltages. Short-circuit protection for both main and auxiliary circuits requires fuses (gL/gG type) up to 10A for Type 2 coordination and 6A for general short-circuit protection.
The relay's robust construction includes screw-type terminals for both power and auxiliary circuits, with specified wire capacities and tightening torques for secure connections. It operates reliably in ambient temperatures from -20 °C to +70 °C (-4 °F to 158 °F), with temperature compensation from -20°C to +60°C. Storage temperatures range from -50 °C to +80 °C (-58 °F to 176 °F). It can operate at altitudes up to 2000m without current reduction.
The relay complies with international standards including IEC 60947-4-1, CSA C.22.2/14, and UL 60947-4-1 (UL 508). It carries important certifications such as Bureau Veritas, CE, IRAM, and UL, ensuring its quality and safety for a wide range of industrial applications.
- Product Type: Thermal Overload Relay
- Manufacturer Part Number (MPN): RW27-1D3-U004
- Reference: RW27
- Number of Poles: 3 poles
- Trip Class: 10
- Current Range: 2.8 - 4 A
- Mounting Type: Direct (to contactor CWM9-40), or by screw/DIN rail with accessory (not included)
- Contactor Model Compatibility: CWM9-40 (direct mounting)
- Rated Insulation Voltage (Ui):
- IEC: 690 V
- UL: 600 V
- Rated Impulse Withstand Voltage (Uimp): 6 kV
- Rated Operational Frequency: 25 - 400 Hz
- Suitable for DC Loads: Yes
- Maximum Operating Frequency: 15 ops./h
- Degree of Protection (IEC 60529):
- Main terminals: IP10
- Auxiliary terminals: IP20
- Max. Fuse (Type 2 Coordination): 10 gL/gG
- Short Circuit Protection with Fuses (gL/gG): 6 gL/gG
- Average Power Dissipation per Pole: 3 W
- Auxiliary Contacts Rated Thermal Current (Ith): 6 A (θ = 55ºC)
- Rated Operational Current (Ie) - AC-14/AC-15 (IEC 60947-5-1):
- 24 V: 4 A
- 60 V: 3.5 A
- 125 V: 3 A
- 230 V: 2 A
- 400 V: 1.5 A
- 500 V: 0.5 A
- 690 V: 0.3 A
- Rated Operational Current (Ie) - DC-DC-13/14 (IEC 60947-5-1):
- 24 V: 1 A
- 60 V: 0.5 A
- 110 V: 0.25 A
- 220 V: 0.1 A
- Power Circuit Terminal Capacity:
- Flex (IEC): 6 mm² ... 10 mm²
- Conductors with wire/terminal drive (IEC): 1.5 mm² ... 6 mm²
- Wire/cable AWG (UL): 18 AWG ... 2 AWG
- Power Circuit Tightening Torque: 2.3 N.m (IEC) / 20 lb.in (UL)
- Auxiliary Contacts Terminal Capacity:
- Flex cable (IEC): 1 mm² ... 2.5 mm²
- Wire/cable AWG (UL): 16 AWG ... 12 AWG
- Auxiliary Contacts Tightening Torque: 1.5 N.m (IEC) / 13 lb.in (UL)
- Ambient Operating Temperature: -20 °C (-4 °F) ... +70 °C (158 °F)
- Temperature for Transport and Storage: -50 °C (-58 °F) ... +80 °C (176 °F)
- Temperature Compensation (IEC 60947-4-1): -20 °C (-4 °F) ... +60 °C (140 °F)
- Operating Altitude: Up to 2000 m (6562 ft)
- Dimensions (H x W x D): 72 mm (2.83 in) x 45 mm (1.77 in) x 82 mm (3.23 in)
- Gross Weight: 0.165 kg (0.36 lb)
- Standards: IEC 60947-4-1, CSA C.22.2/14, UL 60947-4-1 (UL 508)
- Certifications: BUREAU VERITAS, CE, IRAM, UL
- Motor Overload Protection: Safeguards three-phase, single-phase AC, and DC motors against damage from overcurrents and phase loss.
- Direct Contactor Mounting: Seamlessly integrates with CWM9-40 contactors without additional accessories.
- Thermal Trip Class 10: Provides standard, reliable protection against motor overheating.
- Wide Current Range: Adjustable from 2.8A to 4A for versatile application.
- Dual AC/DC Compatibility: Suitable for protection in both AC and DC motor circuits.
- High Insulation and Impulse Withstand: Ensures electrical safety and robustness against voltage spikes.
- IP Protection: Main terminals IP10, auxiliary terminals IP20 for basic ingress protection.
- Flexible Connection Options: Accommodates various wire sizes with specified tightening torques for secure wiring.
- Broad Temperature Range: Operates effectively in demanding industrial environments from -20°C to +70°C.
- Globally Certified: UL, CE, IRAM, and Bureau Veritas certifications ensure compliance and reliability.