5.3 Chapter Conclusion
David Ridge
Summary
This chapter reviewed some basic principles of electricity as they apply to welding and an overview for how welding machines work. There are a wide variety of welding machines in use today, each with different capabilities and characteristics. Finally, some safety considerations that should be taken into account concerning welding machines and electrical power were covered.
Welding machines are complex tools; understanding how they work takes time and study. However, the more familiar you are with the equipment you will be using, the better and safer of a welder you will be. A key aspect of being an effective welder is your knowledge of how to operate your welding machine.
Review Questions
- What part does voltage play in an electric current?
- What part does amperage play in an electric current?
- In what way(s) does voltage affect the weld?
- In what way(s) does amperage affect the weld?
- DCEP and DCSP are terms that both mean the same thing.
- True
- False
- DCEN and DCSP are terms that both mean the same thing.
- True
- False
- If the electricity in the welding system is flowing to the workpiece lead, across the arc, and back through the electrode lead, the welding machine is set up for:
- AC
- DCEP
- DCSP
- DCEN
- If the electricity in the welding system is flowing to the electrode lead, across the arc, and back through the workpiece lead, the welding machine is set up for:
- AC
- DCEP
- DCRP
- DCEN
- In North America, AC operates at what Hz, or cycles per second?
- 100 Hz
- 60 Hz
- 50 Hz
- 20 Hz
- What is the primary difference between CC and CV?
- Processes like FCAW and GMAW use CC power.
- True
- False
- Please list three different types of welding power sources.
- What does the term duty cycle refer to?
- A welding machine has a list of its duty cycle ratings. The list reads as follows: 100% at 90A, 80% at 120A, 60% at 150A, and 40% at 180A. If you needed to weld at 160A-170A on a large weldment, for approximately how long could you weld continuously with this machine? Would this machine be the best choice for a high-production environment? Why or why not?
- At what amperage can an electric current be lethal?
- Why is excess heat in a welding system bad? What can excess heat in the system indicate? How can it be corrected?