<\/figure>\n\n\n\nWhen welding is done with GMAW process using non-ferrous electrodes, a curve having a slope of 1-1\/2 to 2 volts per 100 amperes is suitable. This slope also works for SAW and FCAW processes with higher electrode diameters. This corresponds to the flatter curve in the above figure.<\/p>\n\n\n\n
When carbon dioxide is used as the shielding gas in GMAW, and in small diameter FCAW process, a slope of 2 to 3 volts per 100 amperes is found to be more suitable. This corresponds to the medium slope curve in the above figure.<\/p>\n\n\n\n
When short circuiting arc transfer mode is adopted in gmaw process, a slope of 3 to 4 volts per 100 amperes is recommended. This corresponds to the steeper slope curve in the above figure.<\/p>\n\n\n\n
The dynamic characteristics of the constant voltage power source must be carefully designed to cater to abrupt changes in the voltage. For example, if a sudden change in voltage occurs due to short circuit, the current increases rapidly to a high value. This is a good feature for starting the arc, but this creates spatter if not controlled.<\/p>\n\n\n\n
This control is brought about by adding inductance or reactance to the circuit. This changes the response time of the machine to the sudden changes in the voltage, and enables a stable arc. A difference amount of inductance is inbuilt for different slopes in most machines.<\/p>\n\n\n\n
A constant voltage power source is used for GMAW process. The polarity used us DCRP. DCEN polarity is not preferred because it produces an erratic unstable arc. The properties of the weld are not good. However, DCEN polarity is easily usable for submerged arc welding and flux cored arc welding. <\/p>\n\n\n\n
Alternating current is normally not used with constant voltage power source. Also, constant voltage source is not used for shielded metal arc welding either.<\/p>\n\n\n\n
So this was about welding with constant voltage. Please share your observations in the comments section below.<\/p>\n","protected":false},"excerpt":{"rendered":"
In welding \u2013 besides the current current power source, the second type of power source is the constant voltage (CV) machine or the constant potential (CP) machine. It has a relatively flat volt-ampere characteristic curve. In this article we shall discuss about arc welding with constant voltage. Features Of A Constant Voltage Machine The figure below shows … Read more<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[105],"tags":[4],"yoast_head":"\nArc Welding With Constant Voltage<\/title>\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n\t \n\t \n\t \n