Features Built-in regular standby opening signal output port, which can be connected with signal indicator light, which is convenient for observation outside the cabinet. The use of silver contacts can greatly improve the conductivity and service life of the product. When the normal power supply is abnormal, the backup power supply will work immediately to ensure the continuity, reliability and safety of the power supply. Using high-quality flame-retardant plastic material, good insulation, high temperature resistance, anti-aging, safe and reliable. Suitable for switching to the backup power supply when the power is cut off, and switching to the main power supply when the power comes in. Specifications: Material: Plastic Purpose: Switch to the backup power supply when the power fails, and switch to the main power supply when the power comes in Working Frequency: 50-60Hz Rated Current: 100A Rated Voltage: AC110-230V Working Voltage: AC400V Control voltage: AC220V Operation Mode: Automatic and manual ATS: CB level Conversion Time: ≤0.05 (S) How to Use: 1. Place the automatic transfer switch of the dual power supply on the debugging platform, and connect the corresponding power line according to the correct phase sequence. The phase line and the neutral line are connected in position, and the wrong connection is not allowed. 2. When debugging the three-pole switch, the common and spare neutral wires should be connected to the neutral terminal (NN and RN) respectively. 3. Set the dual power supply automatic transfer switch to work in the self-turning and self-resetting mode. If the voltage of the two power supplies is normal, the switch should be placed in the common power supply position, and the common power supply is closed. 4. Set the common power supply NA, NB, NC, NN for any phase loss, the dual power supply should be automatically converted to the backup power supply, if the common power supply returns to normal, it should be converted back to the common power supply. 5. Adjust the voltage of any phase of the common power supply to the predetermined undervoltage voltage value, and the dual power supply should automatically switch to the standby power supply. When the normal power supply returns to normal, the switch should return to the normal power supply. Warm tips: This product is only suitable for mains/generator power supply; it cannot be used for inverter, UPS, photovoltaic, solar power generation. Packing list: 1 x Dual Power Automatic Transfer Switch  1 x User Manual    Package List 1 x Dual Power Automatic Transfer Switch 1 x User Manual