I. Safety Standards and Pre-Operation Inspections
1. Equipment Inspection
Confirm the power supply is stable and check if the welding machine casing is grounded to prevent leakage.
Check the welding torch and cable for damage to avoid the risk of electric shock.
The working environment should be dry and well-ventilated, away from flammable materials. If the ground is damp, lay an insulating mat.
Prepare fire extinguishing equipment. Wear a safety belt when working at heights.
2. Parameter Settings
After connecting the power, switch the welding mode from "Discharge" to "Welding".
Adjust the current according to the material thickness: thicker materials require higher current; welding aluminum requires switching to AC mode and enabling the pulse function.
II. Positive and Negative Terminal Wiring Methods
1. Differentiating Welding Machine Types
DC welding machines (marked DC) require strict differentiation of positive and negative terminals; AC welding machines (marked AC) have no polarity requirements.
2. DC Welding Machine Wiring Method
Positive Connection: Connect the workpiece to the positive terminal and the welding clamp to the negative terminal. With deep penetration and narrow weld seam, it is suitable for thick steel plates.
Reverse connection method: Connect the workpiece to the negative terminal and the welding clamp to the positive terminal. Stable arc and less spatter, suitable for thin plates, stainless steel, and basic welding rods (such as 506 and 507).
Memory aid: Connecting the ground wire to the positive terminal is the correct connection; connecting it to the negative terminal is the reverse connection.
III. Cable Selection and Wiring Specifications
1. Cable Requirements: Use waterproof rubber-sheathed copper core flexible cable. The cross-sectional area must match the current (e.g., 500 amps requires a cable of 50 square millimeters or more).
It is forbidden to use metal components to replace the ground wire. Joints must be insulated and waterproofed.
2. Voltage and Length Limitations: The open-circuit voltage on the secondary side shall not exceed 80 volts AC or 100 volts DC, and the cable length shall not exceed 30 meters.
Avoid cables crossing roads or draped over steel structures to form loops.
3. Three-phase welding machine wiring: Match the power supply voltage (220V/380V), connect the three live wires to terminals L1, L2, and L3, and connect the neutral and ground wires to their respective terminals.
IV. Operating Precautions
1. Safety Protection: Wear a welding mask, flame-retardant work clothes, and insulated gloves. Work clothes must be fastened tightly.
2. Final Inspection: After turning off the power, test for voltage. Welding slag must be soaked in water. Periodically measure the insulation resistance (not less than 1 megohm).
3. Common Mistakes: Using alkaline welding rods with the correct polarity can cause porosity; using the correct polarity on thin plates can easily burn through.
