Common knowledge and safety points of electric welder

AC welding machine is a special structure of step-down transformer, no-load voltage is 60-80V, working voltage is 30V; power 20-30kW, secondary current is 50-450A; power supply voltage 380/220 V. DC welding machine uses a three-phase motor to drive a special structure of the DC generator; silicon rectifier DC welding machine is the use of silicon rectifier components to convert AC into DC; welding machine secondary line no-load voltage 50-80V, working voltage 30V, welding current 45-320A; welding machine power 12-30kW, power supply voltage 380 V and 220V. AC and DC electric welding machines should be startup without load, DC generator electric welding machines should rotate in the prescribed direction, with the fan should pay attention to the fan rotation direction is correct. The welding machine should be connected to the three-phase power grid at the same time, so that the three-phase load can be balanced as far as possible. When the welding machine needs to be used in parallel, the primary line should be connected in parallel to the same phase circuit; the secondary side should also be connected in the same phase, and the welding machine with different no-load voltage on the secondary side should be adjusted to be equal before it can be used, otherwise it can not be used in parallel. YHS rubber sheath copper core multi-ply flexible cable should be used. The length is not more than 30m. The cable should not be disc-shaped during operation. Otherwise, the welding current will be affected. When several welding machines are used at the same time, when a certain one needs to be dismantled, the power should be cut off first, and then the electricity should be tested on one side of the welding machine. All metal casing of AC and DC welding machines must be protected earthed or connected to zero. Grounding and zero resistance should be less than 4 ohms. The secondary winding of the welding machine is forbidden to be grounded or zero-connected when the welding metal equipment and container are grounded or protected by zero-connection. The grounding and zero-connection wires of multiple welding machines shall not be connected to the grounding body in series. Each welding machine shall be equipped with independent grounding and zero-connection wires, and the contacts shall be tightened by screws. Each welding machine should be equipped with a special circuit breaker and an over-current protection device matched with the welding machine. The primary wire and the power supply connection should not be connected with pins, and the length should not exceed 5m, and must be double insulation. The overlap area should be guaranteed when the second side of the welding machine and the ground wire need to be connected for a long time. The contact area should be wrapped with insulating tape, and the contact should not exceed two points. The primary and secondary terminals of the welding machine should have protective covers, and the primary terminals should be wrapped tightly with insulating tape; the secondary terminals must be firmly pressed with wire clips. Welders should be placed in dry and ventilated places (except water-cooled), open-air use should be damp-proof below and higher than the surrounding ground; the upper part should be protected against rain canopy and smash measures.铜焊丝,Copper Welding Rods,铝焊丝,aluminium welding wire,镍焊条,Nickel electrode,药皮焊条,Flux Coated Brazing Welding Rods