2T vs. 4T in Welding
2T and 4T are two modes of operation found on welding machines, which control how the welder triggers and maintains the welding arc.
2T stands for "Two-Touch" or "Two-Trigger" and is the most common mode of operation. In 2T mode, the welder initiates the arc by pressing and holding the trigger on the welding torch. The arc remains on as long as the trigger is held down. Once the trigger is released, the arc is extinguished.
4T stands for "Four-Touch" or "Four-Trigger" and is a less common mode of operation. In 4T mode, the welder initiates the arc by pressing and releasing the trigger on the welding torch. The arc remains on even after the trigger is released, and the welder can move their hand away from the trigger to reposition themselves or the workpiece. To turn off the arc, the welder presses the trigger again.
The main advantage of 4T mode is that it allows the welder to maintain the welding arc without having to keep the trigger pressed down, which can be more comfortable and reduce hand fatigue during long welding sessions. It also allows for greater control over the welding process, as the welder can focus on positioning the torch and filler material without worrying about the trigger.
However, 2T mode is often preferred for shorter welds or for welding in tight spaces, as it allows for more precise control over the welding arc and can be quicker to initiate and extinguish the arc.
Ultimately, the choice between 2T and 4T mode depends on the specific welding application and the preferences of the welder. Some welding machines may also have additional modes of operation, such as a foot pedal control or a spot welding mode, which can provide even more control over the welding process.