Automatic Transfer Switch Instruction Manual

1. Product Overview

The EARU EAATS-F-CG-80 is a PC class infrequent change-over switch designed for automatic transfer between two power sources. It features a two-station design, commonly used for a primary (main) power supply and a secondary (backup) power supply. This device is suitable for AC systems with a frequency of 50-60Hz and a rated current of 6-63A.

Its primary function is to automatically switch to the backup power supply (Backup power supply B) when the main power (common power supply A) fails. This transfer occurs rapidly, typically within 20 milliseconds, effectively preventing operational disruptions caused by power outages.

Key features include millisecond switching, uninterruptible power supply, PC level protection, flame-retardant material, low energy consumption, and high precision.

2. Specifications

The following table outlines the main technical parameters of the Automatic Transfer Switch:

Note: If the rated working voltage is AC110V, the product needs to be customized.

3. Dimensions

The compact design of the ATS ensures space optimization while maintaining performance and efficiency. Below are the detailed dimensions:

• Overall Height: 110mm (4.33in)
• Overall Width: 50mm (1.97in)
• Overall Depth: 78mm (3.07in)
• Top Width: 46mm (1.81in)
• Top Depth: 59mm (2.32in)

Terminal wiring area is suitable for 1-25mm² wires. The wire connection screw is M5, with a recommended torque of 2.5N.m.

4. Installation

Before proceeding with installation and wiring, ensure that qualified professionals have thoroughly read and understood this manual.

4.1 Pre-Installation Check

1. Check the integrity of the ATS unit.
2. Turn on the ATS using the operating handle to verify the flexibility of the operating mechanism.
3. Confirm the opening and closing status of each phase for both normal and backup power loads.
4. Equip the ATS with suitable circuit breakers according to the power distribution system's installation requirements to ensure personnel and equipment safety.

4.2 Mounting

The ATS is designed for 35MM Din Rail installation and can be directly installed in a household lighting distribution box.

5. Wiring Instructions

Refer to the diagram below for proper wiring connections. Ensure all connections are secure and meet local electrical codes.

• City Power: Connect the main power supply to the designated terminals (Common Power Live Wire, Common Power Neutral Wire).
• Generator: Connect the backup power supply (e.g., generator) to the designated terminals (Backup Power Live Wire, Backup Power Neutral Wire).
• Load: Connect the load to the Load Output Live Wire and Load Output Neutral Wire terminals.
• Ensure the correct polarity for all connections.
• The terminal wiring area is designed for 1-25mm² wires. Use an M5 screw with a torque of 2.5N.m for wire connections.

6. Operating Modes

The ATS supports both automatic and manual operation modes, allowing users to seamlessly switch between them as required.

6.1 Automatic Mode

In automatic mode, the system automatically switches to the backup power supply during a primary power failure and switches back to the main power when it is restored. This ensures uninterrupted power supply with a transition time of less than 20 milliseconds.

6.2 Manual Mode

The device features a manual handle and manual/automatic adjustment buttons for mode selection. In manual mode, you can manually adjust the power supply. This mode is primarily for inspection and maintenance.

6.3 Operation Demonstration Video

Watch this video for a demonstration of the automatic and manual switching functions:

7. Working Conditions

• Temperature Range: The operating environment temperature should be between -5°C and +40°C. The average temperature within 24 hours must be lower than +35°C. The storage temperature range is -25°C to +55°C, with short-term (within 24 hours) peaks up to +70°C.
• Altitude: The installation site altitude should be lower than 2000m.
• Relative Humidity: The relative humidity at the installation site should not exceed 50% when the ambient air temperature is +40°C. Higher relative humidity is permissible at lower temperatures. For example, at an average minimum temperature of +20°C in the wettest month, the monthly average maximum relative humidity can reach 90%. Appropriate measures should be taken to prevent condensation due to temperature changes.
• Pollution Level: Pollution level 3 (conductive pollution, or dry non-conductive pollution becomes conductive due to condensation).
• Installation Orientation: The ATS can be installed vertically or horizontally in the cabinet. For special installation requirements, please contact support.

8. Important Notes

• When performing manual operation, the mode selection switch MUST be in the 'Manual' position.
• The switch cannot be manually operated when in automatic mode. Attempting to do so may cause damage to the internal coil.
• Manual/automatic operation ensures the opening and closing performance of electrical operation. However, in manual operation, there is no guarantee of consistent opening/closing speeds, which could lead to excessive silver alloy loss. Therefore, the selector switch should only be pulled to the manual position after all power has been cut off for inspection and maintenance. Normally, keep the selector switch in the electric (automatic) position.
• The control circuit ATSE is immediately energized. After the changeover is completed, the internal switch will damage the coil in the control circuit. The coil can work normally at 85% ~ 110% of the rated operating voltage. Too low input voltage may cause the coil to overheat and burn out.

9. Maintenance

Maintenance and inspection should only be carried out by qualified professionals.

9.1 Maintenance Schedule

• The first maintenance and inspection should be performed within 6 months after initial use to ensure optimal performance.
• Subsequently, maintenance and inspection should be conducted at least once a year.
• In harsh installation conditions, increase the frequency of maintenance and inspection.

9.2 Maintenance Procedures

1. If maintenance items fail, remove any accumulated dust.
2. Check whether the electrical contact parts are deformed or damaged, and clean their surfaces. Look for metal particles or burnt areas around the contacts.
3. Rust, acidification, and dust on contact surfaces can cause poor contact. Perform manual cleaning and measure the necessary contact resistance.
4. If the ATS is wet or has been left unused for a long time, ensure it is thoroughly dried before powering it on.
5. After removing dust, use a 500V megohmmeter to measure the insulation resistance of the normal power supply and the AC power supply. The insulation resistance between the load side and two poles, including live parts and metal plates, should not be less than 10MΩ.

10. Basic Troubleshooting

This section provides general guidance for common issues. For complex problems, consult a qualified electrician.

• No Power Transfer: Check if both primary and backup power sources are active. Ensure the ATS is in 'AUTO' mode. Verify all wiring connections are secure.
• Manual Mode Not Working: Ensure the mode selection switch is firmly in the 'MANU' position. If the switch feels stiff or unresponsive, do not force it; inspect for obstructions or internal damage (after disconnecting power).
• Overheating/Burning Smell: Immediately disconnect power to the unit. This could indicate an overload, short circuit, or internal component failure. Do not attempt to operate the unit until inspected by a professional.
• Intermittent Operation: Check for loose wiring connections, unstable power sources, or environmental factors (e.g., extreme temperatures, humidity) affecting performance.

11. User Tips

• Power Source Compatibility: This ATS is designed for AC 230V (or 110V customized) 50/60Hz systems. Ensure your primary and backup power sources (e.g., city grid, generator) are compatible with these specifications.
• Inverter Use: If using a DC or low voltage power supply (such as from solar panels or a car charger), an inverter is required to convert it to 230V AC (or 110V AC) before connecting to the ATS. This ATS cannot be directly used with DC or low voltage sources without proper AC conversion.
• Phase Consistency: When connecting two city voltage inputs, ensure phase consistency if applicable to avoid issues during transfer.
• Professional Installation: For safety and optimal performance, always have the ATS installed by a qualified electrician.

12. Frequently Asked Questions (FAQ)

Q: Can this ATS be used with solar panels and a car charger?

A: This ATS is designed for AC 230V (or 110V customized) 50/60Hz systems. If your solar panels or car charger provide DC or low voltage power, you will need an appropriate inverter to convert it to the required AC voltage before connecting to the ATS. The ATS cannot be directly used with DC power sources.

Q: Can I connect two city voltage inputs to this automatic transfer switch?

A: Yes, the ATS is designed to switch between two power sources. If both inputs are city voltage, ensure they are compatible with the ATS specifications (AC 230V/220V, 50/60Hz) and that phase consistency is maintained if applicable.

Q: Can this ATS be applied to photovoltaics?

A: Yes, but indirectly. Photovoltaic (solar) systems typically produce DC power. To use this ATS with a photovoltaic system, you must first convert the DC power to AC power using a suitable inverter. The AC output from the inverter can then be connected as one of the power sources to the ATS.

13. Warranty and Support

For any technical assistance, warranty claims, or further inquiries, please contact EARU Official Store customer support. Please refer to the official product page or your purchase documentation for specific warranty terms and conditions.

You can also refer to the official user manual PDF for additional details: View User Manual (PDF)