Select a recommended welding polarity based on process, electrode or wire type, and material.
Welding polarity describes the direction of electrical current through a direct-current welding circuit. It determines which terminal of the welding power source is connected to the electrode and which is connected to the workpiece.
The two common DC arrangements are DCEP and DCEN.
Some welding processes and consumables can also operate with alternating current, or AC. The correct choice depends on the electrode or wire classification and the manufacturer's welding procedure.
| Polarity | Electrode Connection | Work Connection | Common Applications |
|---|---|---|---|
| DCEP | Positive (+) | Negative (−) | Common for many SMAW electrodes, GMAW and some FCAW applications. |
| DCEN | Negative (−) | Positive (+) | Common for GTAW with many steels and some specific electrode/wire applications. |
| AC | Alternating | Alternating | Used by specific electrodes and processes where AC is specified. |
Stick electrodes have polarity requirements that depend on the electrode classification.
| Electrode | Typical Current Type | Common Polarity |
|---|---|---|
| E6010 | DC | DCEP |
| E6011 | AC or DC | Usually DCEP on DC |
| E6013 | AC or DC | Often DCEP or DCEN depending on application and manufacturer |
| E7018 | AC or DC | DCEP is commonly used on DC |
| E7018-AC | AC or DC | AC or DCEP according to manufacturer |
Conventional GMAW with solid wire and shielding gas is commonly operated using DCEP. This supports stable metal transfer for many commonly used solid-wire welding applications.
The exact wire classification, shielding gas, transfer mode and welding procedure can affect the recommended settings.
Some special wires and processes use different arrangements, so the wire manufacturer's specification should always be checked.
GTAW/TIG commonly uses DCEN when welding steels, stainless steels, copper and many other metals because the tungsten electrode is normally connected to the negative terminal.
Aluminum and magnesium are commonly welded using AC TIG because the alternating current provides characteristics useful for managing the oxide layer on these metals.
Modern TIG power sources may provide adjustable AC balance and waveform controls, so the manufacturer's recommended settings should be followed.
Flux-cored welding polarity depends heavily on the wire classification.
Many gas-shielded FCAW wires are designed for DCEP, while some self-shielded flux-cored wires are designed for DCEN.
| FCAW Type | Typical Polarity |
|---|---|
| Gas-shielded FCAW | Often DCEP |
| Self-shielded FCAW | Often DCEN, depending on wire classification |
Changing DC polarity changes the direction of current through the arc and can affect arc characteristics, penetration, electrode behavior, deposition and weld appearance.
Using the wrong polarity can result in unstable arc behavior, excessive spatter, poor penetration, difficult arc starts or unsatisfactory weld quality.
For production welding, polarity should be treated as part of the qualified welding procedure rather than a setting chosen only by trial and error.
The polarity names describe the electrode connection, which makes them easier to remember.
This tool provides a general polarity recommendation based on common welding practice. It does not replace the welding electrode, filler-wire or equipment manufacturer's instructions.
A specific consumable can have polarity requirements that differ from the general process recommendation.
What polarity is most common for stick welding? Many common stick electrodes use DCEP on DC, but polarity depends on the electrode classification. E6010, E6011, E6013 and E7018 do not all have identical requirements.
What polarity is normally used for MIG welding? Conventional solid-wire GMAW is commonly operated using DCEP.
What polarity is normally used for TIG welding? DCEN is commonly used for TIG welding of steels, stainless steels and many other metals. AC is commonly used for aluminum and magnesium.
What polarity is used for aluminum TIG? AC is commonly used because it provides the alternating-current behavior needed for aluminum oxide management.
What does DCEP mean? DCEP means direct current electrode positive. The electrode is connected to the positive terminal.
What does DCEN mean? DCEN means direct current electrode negative. The electrode is connected to the negative terminal.
Can E6013 be used on DCEN? Some E6013 electrodes permit DCEN, while others specify different current or polarity options. Always check the exact electrode manufacturer's data.
Can E7018 be used on AC? Many E7018 electrodes are available for AC operation, particularly electrodes specifically classified for AC. The manufacturer's specification should be checked.
Does polarity affect penetration? Changing polarity can change arc characteristics and heat distribution, which can affect penetration and weld behavior. The effect depends on the welding process and consumable.
What happens if the wrong polarity is used? The arc may become unstable and the weld can exhibit excessive spatter, poor penetration, difficult starting or other undesirable characteristics.