Welders use arc welding electrode charts to determine the type of coating and welding current used for a given electrode. Use the amperage charts to determine the current value for use on a given electrode diameter.
Check the code on a given electrode against a chart to determine the metal type, strength, coating, welding position and the weld position of the electrode. The letter E on a welding rod labeled E6010, for instance, signifies that the rod is an electrode for arc welding. The first two digits indicate the tensile strength of the material in pounds per square inch, while the third digit indicates the position of the weld. The fourth and fifth digits indicate the electrode coating used and the right weld current for use, although the digit combinations may vary.
Read the last two digits of an arc welding electrode code to understand the coating and current polarity to use with the electrode. A code ending with 11, for instance, means the electrode has a high cellulose potassium coating, and the welder may use alternating current or direct current of either polarity. Additionally, use the amperage chart to determine the amperage range for use with a given rod diameter. Use a current between the minimum and maximum values but less than maximum current for vertical position.