B-6

OPERATION

B-6

 

 

 

Instead, an arc length adjustment is provided. The machine “knows” what the best arc length is at the given wire feed speed but allows the operator to change it.

The arc length trim (usually referred to simply as “trim”) can be adjusted between 0.500 and 1.500 on the control box’s Volts/Trim display. A Trim of 1.000 means that no adjustments will be made to the preset arc lengths. A Trim greater than 1.000 increases the preset arc lengths. A Trim setting less than 1.000 decreases the preset arc lengths. The arc length trim adjustment is factored in at all wire feed speed set- tings. Increasing the Trim by 10 percent at a given wire feed speed also increases all the other arc length trim settings of the procedure by 10 percent.

The Power Wave utilizes a control scheme known as adaptive control in all pulse modes. Because the Power Wave utilizes adaptive control, it can adjust the pulsing parameters based on changes in the arc due to changes in the electrical stickout of the electrode. (Electrical stickout is the distance from the contact to to the workpiece.) The Power Wave is optimized for use with a 19 mm (.75”) stickout. The adaptive behavior is programmed to support a stickout range from 13 mm (.5”) to 32 mm (1.25”). In the low and high end of the wire feed speed ranges of most processes, the adaptive behavior may be restricted. This is a physical restriction due to reaching the edge of the operating range for the process.

The Arc Control adjustment allows the pulse frequen- cy to be varied. Increasing the Arc Control causes the frequency setting to increase, while decreasing the Arc Control causes the frequency to decrease. Varying the Arc Control, and hence, the pulse fre- quency, affects the droplet transfer and allows fine- tuning for different welding positions.

CONSTANT CURRENT (CC/STICK, CC/TIG) PROCEDURES

Stick welding can be performed by choosing one of the stick welding modes. Check the Power Feed wire feeder Operator’s Manual for instructions on how to energize the output terminals on the Power Wave. (Certain options energize the terminals automatically while other options require a manual adjustment to energize the terminals.) The output current is set by the Amps control on the Power Feed wire feeder. The Volts/Trim adjustment has no effect in this mode.

The Arc Control adjusts the arc force. Increasing the Arc Control setting increases the arc force, making the arc more harsh but less likely to stick. Decreasing the Arc Control setting decreases the arc force, mak- ing the arc softer and smoother.

ARC GOUGING PROCEDURES

Arc gouging can be performed by choosing the arc gouging weld mode. Doing so automatically ener- gizes the output terminals on the Power Wave, mak- ing the power source immediately ready to weld. The output current is set by the Amps control on the Power Weld wire feeder. The Volts/Trim adjustment has no effect in this mode.

The Arc Control adjusts the arc force. Increasing the Arc Control setting increases the arc force, making the arc more harsh but less likely to stick. Decreasing the Arc Control setting decreases the arc force, mak- ing the arc softer and smoother.

SURFACE TENSION TRANSFER (STT) PROCEDURES

The STT process is neither a constant current (CC) nor a constant voltage (CV) process. It is a current controlled process where the electrode current changes quickly in response to the instantaneous requirements of the arc.

In the Power Wave 455/STT, the ideal STT wave- forms and current control alogorithms are pro- grammed into the power source. These waveforms are automatically adjusted as the wire feed speed is varied on the Power Feed wire feeder. This is known as synergic control of the STT process. Some adjust- ments are available to the user, so that the arc can be adjusted to meet the actual weld conditions.

The Arc Control setting is a coarse adjustment of the heat input to the weld. It can be varied from -10.0 to 10.0, with a nominal setting nof 0.0. Reducing the Arc Control too far may cause electrode stubbing. Raising the Arc Control too high may cause the electrode to be too fluid, increasing spatter. An Arc Control setting of 0.0 is a good starting point for most conditions.

The Trim is a fine adjustment of the heat input to the weld. It can be varied from 0.500 to 1.500. A Trim setting of 1.000 is a good starting point for most condi- tions.

POWER WAVE 455 STT

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Lincoln Electric 455 manual Constant Current CC/STICK, CC/TIG Procedures, ARC Gouging Procedures