What is OCV?

Open circuit voltage (also called no-load voltage) is the voltage that exists between the electrode and the workpiece (or earth) when not welding.

How is OCV different from Welding Voltage?

OCV should not be confused with Welding Voltage. Welding voltage is the voltage that exists between the electrode and the job (or the earth) during welding, and this is what maintains the arc between the electrode and the job.

Welding voltage will typically be much lower than OCV, and will vary with many parameters (such as arc length, etc.).

What does OCV affect stick welding performance?

OCV works in a similar way to a hot start function, as a “higher” OCV improves the ease of electrode ignition (and also helps maintain a strong/stable arc), which is especially beneficial when using electrodes that are difficult to run, such as Low hydrogen.

Broadly speaking;

Machines with an OCV below 50V will have “fair to poor” arc characteristics. Many older transformer machines (especially single phase) usually have an OCV of 40-45V. These machines can be used with general purpose electrodes that may be difficult to run electrodes such as low hydrogen electrodes, certain types of stainless steel, surfacing and other more specialized rods that require a higher OCV.

Machines with an OCV of 50V and above will provide “good” arc characteristics. Most reputable inverter rod/MMA welders have an OCV of 50V or higher.

Machines with an OCV of 75V and above will provide “excellent” arc characteristics. Decapower provides such as ECO MMA OCV, PLUS MMA OCV and so on.