1. Introduction
The EARU EACT-25Z Household DC Contactor is designed for DC circuits operating at 12V or 24V. It is primarily used for automatic cut-off or connection of power in various applications such as homes, apartments, and hotels. This modular contactor is suitable for circuits with a breaking capacity below 6kA.
This manual provides essential information for the safe and efficient installation, operation, and maintenance of your EACT-25Z DC Modular Contactor.
2. Safety Precautions
WARNING: Electrical installation should only be performed by qualified personnel. Always disconnect power before installation or maintenance.
- Ensure the contactor's specifications match the intended application and working conditions before installation.
- Verify correct connection modes for all wiring.
- Securely tighten all binding screws during connection to prevent loose contacts.
- Observe all local and national electrical codes and regulations.
3. Specifications
Figure 3.1: Dimensions of the EARU EACT-25Z DC Modular Contactor
| Attribute | Value |
|---|---|
| Model Number | EACT-2P-25Z |
| Main Circuit Rating Current | 16A, 25A |
| Main Circuit Rating Voltage | DC 12V / 24V |
| Number of Pole | 2 |
| Electricity Type | DC |
| Phase | 1 |
| Brand Name | EARU (ELESAVEE, EARUELETRIC) |
| Origin | Mainland China |
| Certification | CE |
| Dimensions (approx.) | 85mm (H) x 18mm (W) x 66mm (D) |
Figure 3.2: Detailed Technical Data and Connection Information
Additional Technical Characteristics
- Power Circuit Voltage Rating (Ue): 250V AC (for 1P, 2P), 400V AC (for 3P, 4P) - Note: This product is designed for DC applications as specified in the main circuit rating.
- Frequency: 50Hz or 60Hz
- Electrical Endurance: 100,000 cycles
- Maximum Number of Switching Operations per Day: 100
- Insulation Voltage (Ui): 500 V AC
- Pollution Degree: 2
- Rated Impulse Withstand Voltage (Uimp): 2.5kV (4 kV for 12/24/48V versions)
- Degree of Protection: IP20 (device only), IP40 (when installed in a modular enclosure)
- Operating Temperature: -5°C to +60°C
- Storage Temperature: -40°C to +70°C
- Tropicalization (IEC 60068-1): Treatment 2 (relative humidity 95% at 55°C)
- ELSV Compliance: (Extra Low Safety Voltage) for 12/24/48V versions. The product conforms to SELV (safety extra low voltage) requirements.
Note: If the contactor is mounted in an enclosure where the interior temperature is between 50°C and 60°C, it is necessary to use a spacer between each contactor to ensure proper heat dissipation.
4. Installation
4.1 Environmental Conditions
- Ambient Temperature: -5°C to +40°C, with an average temperature not exceeding +35°C over 24 hours.
- Altitude: Not exceeding 2000m.
- Atmospheric Conditions: Relative humidity should not exceed 50% at +40°C. Higher relative humidity is permissible at lower temperatures. The monthly average minimum temperature in the wettest month should not exceed +25°C, and the monthly average maximum relative humidity for that month should not exceed 90%. Condensation due to temperature changes should be considered.
- Class of Pollution: Class 2.
- Installation Condition: Class II.
4.2 Mounting on DIN Rail
The EACT-25Z contactor is designed for easy mounting on a standard 35mm DIN rail.
- Ensure the power supply is disconnected before installation.
- Locate the motion stopping component (yellow clip) on the bottom of the contactor.
- Pull down the motion stopping component.
- Position the contactor onto the DIN rail.
- Push up the motion stopping component to securely fix the contactor on the rail. This prevents loosening and accidental dropping.
- To remove the contactor, pull down the motion stopping component and lift the contactor off the rail.
Video 4.1: Demonstration of DIN rail mounting and removal for the EACT-25Z contactor.
4.3 Wiring Connections
Refer to the technical data and wiring diagrams for appropriate cable types and tightening torques. Ensure all connections are secure.
| Type | Rating | Tightening Torque (Control) | Tightening Torque (Power) | Rigid Cable Size | Flexible/Ferrule Cable Size |
|---|---|---|---|---|---|
| PZ1:4mm | 16-100A | 0.8 N.m | 3.5 N.m | 1.5 to 2.5 mm² | 1.5 to 2.5 mm² |
| PZ2:6mm | 40-63A | 0.8 N.m | 3.5 N.m | 1.5 to 6 mm² | 1 to 4 mm² |
| PZ1:4mm | 100A | 0.8 N.m | 3.5 N.m | 6 to 35 mm² | 6 to 35 mm² |
Figure 4.2: Contact Configurations and Wiring Diagrams
For the 2-pole EACT-25Z model, common contact configurations include 2NO (Normally Open), 1NO+1NC (Normally Open + Normally Closed), and 2NC (Normally Closed), depending on the specific variant purchased.
5. Operation
The EACT-25Z DC Modular Contactor functions as an automatic switch to connect or disconnect power in a circuit. Once installed and wired correctly, its operation is typically controlled by an external signal (e.g., from a smart home system, timer, or manual switch) applied to its control terminals (A1/A2 or R1/R2). When the control voltage is applied, the contactor's main contacts will close (for NO contacts) or open (for NC contacts), thereby controlling the power flow to the connected load.
The status indicator on the front of the contactor will show whether the contacts are open or closed.
6. Maintenance
Regular maintenance helps ensure the longevity and reliable operation of your contactor.
- Visual Inspection: Periodically inspect the contactor for any signs of physical damage, discoloration, or loose connections.
- Cleaning: Keep the contactor free from dust and debris. Use a dry, soft cloth for cleaning. Do not use liquids or abrasive cleaners.
- Connection Check: Re-tighten terminal screws if necessary, especially after initial installation and during routine checks, to ensure good electrical contact.
- Operational Check: If possible and safe to do so, periodically test the contactor's switching function to ensure it operates smoothly.
Always disconnect power before performing any maintenance or inspection.
7. Troubleshooting
If you encounter issues with your EACT-25Z contactor, consider the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Contactor does not switch (no click sound) | No control voltage; Incorrect control voltage (e.g., 12V unit receiving 24V); Faulty control wiring. | Check control circuit power supply; Verify control voltage matches contactor rating; Inspect control wiring for breaks or loose connections. |
| Contactor switches but load does not receive power | No main circuit power; Faulty main circuit wiring; Overload condition. | Check main power supply; Inspect main circuit wiring and connections; Check for overcurrent and ensure load is within contactor's rating. |
| Contactor hums or buzzes loudly | Loose connections; Contactor coil issue; Incorrect voltage. | Tighten all terminal screws; Ensure correct control voltage is applied; If buzzing persists, the coil may be faulty and require replacement. |
| Contactor overheats | Overload; Poor ventilation; Loose connections. | Reduce load or use a higher-rated contactor; Ensure adequate airflow around the contactor; Tighten all connections. Consider using spacers if installed in an enclosure with high ambient temperature. |
If the problem persists after attempting these solutions, contact a qualified electrician or the product supplier for further assistance.
8. User Tips
- Voltage Matching: Always double-check that the control voltage (12V or 24V DC) of the contactor matches your power source to prevent damage.
- Secure Mounting: Ensure the contactor is firmly clipped onto the DIN rail to avoid vibrations and potential disconnections.
- Wiring Quality: Use appropriate wire gauges for the current rating and ensure all wire ends are properly stripped and inserted into terminals before tightening.
9. Frequently Asked Questions (FAQ)
- Q: Can this contactor be used with AC circuits?
- A: While some technical data mentions AC voltage ratings for the power circuit, the EACT-25Z model is specifically designed and rated for DC 12V or 24V applications. Using it in AC circuits may lead to malfunction or damage.
- Q: What does 1NO 1NC mean?
- A: 1NO 1NC refers to the contact configuration. 1NO means one Normally Open contact, which closes when the coil is energized. 1NC means one Normally Closed contact, which opens when the coil is energized. The EACT-25Z is available in various configurations like 2NO, 1NO+1NC, or 2NC.
- Q: Is this contactor suitable for outdoor use?
- A: The device itself has an IP20 rating, meaning it is protected against solid objects larger than 12.5mm but has no protection against water. When installed in a modular enclosure, the protection increases to IP40, offering protection against solid objects larger than 1mm. For outdoor use, it must be housed within a suitable weatherproof enclosure that provides adequate IP rating for the environment.
10. Warranty and Support
For warranty information, technical support, or service inquiries, please refer to the documentation provided at the time of purchase or contact your supplier directly. Keep your purchase receipt as proof of purchase.
