Chapter 2 Power Sources for Welding Flashcards
- Which statement supports the fact that metals are good conductors?
a. Their electrons are tightly held by the nucleus
b. They have many free neutrons
c. They have many free electrons
d. They have many free proton
c. They have many free electrons
- Which statement best describes ionization potential?
a. The energy required to add an electron to form a negative ion
b. The energy required to remove an electron to form a positive ion
c. The energy released when a electron is removed from an atom
d. The energy required to remove a proton from an atom
b. The energy required to remove an electron to form a positive ion
- A plasma can best be described as:
a. an ionized gas
b. an inert gas
c. a good insulator
d. a high temperature gas
a. an ionized gas
- Choose the minimum temperatures in the centre of a welding arc column in °C.
a. 500
b. 1,000
c. 5,000
d. 50,000
c. 5,000
- The major voltage drop(s) in a consumable electrode welding circuit is (are):
a. the welding cables
b. the work clamp
c. the arc plasma
d. the anode drop, cathode drop and the arc plasma
d. the anode drop, cathode drop and the arc plasma
- The static characteristics of a welding power source are indicated on a graph which plots
a. voltage verses time
b. current verses time
c. energy verses time
d. voltage verses current
d. voltage verses current
- The arc starting characteristics of a CC welding power source are determined by
a. the short circuit current
b. the slope
c. the input voltage
d. the open circuit voltage
d. the open circuit voltage
- A voltage sensing wire feed system must be used with a ___________ to produce a stable
self-regulating welding arc.
a. CC power source
b. CV power source
c. CV inverter power source
d. CV power source with above average droop
a. CC power source
- The short circuit current in a CV welding power source is determined by
a. the static and dynamic characteristics
b. the voltage in the circuit
c. the shielding gas employed
d. the arc length
a. the static and dynamic characteristics
- Select the correct statement.
a. A CC welding power source can be used for the gtaw and paw processes
b. A CC welding power source can be used for the smaw and saw processes
c. A CV welding power source can be used for the gmaw and fcaw processes
d. All of the above
d. All of the above
- The advantage of portable alternator welding power sources utilizing a rotating field design
is ________________________
a. AC auxiliary power can be produced as well
b. more reliable, as less current flows through the brushes
c. rectifiers can be used to produce DC power
d. all of the above
d. all of the above
- The conductor size of the secondary windings of a welding transformer power source is
a. the same as the primary winding
b. smaller than the primary winding
c. larger than the primary winding
d. none of the above
c. larger than the primary winding
- Mechanical reactor control is used on which type of welding power source?
a. Silicon-controlled rectifier
b. Inverter
c. Saturable reactor
d. None of the above
d. None of the above
- A saturable reactor power source uses ________________________ to adjust the output.
a. a third winding on the transformer
b. a transistor
c. a tapped transformer
d. a moveable secondary winding
a. a third winding on the transformer
- A rectifier consists of components that
a. change DC power to AC power
b. slows the dynamic response of the power source
c. decreases the frequency of the power source
d. changes AC power to DC power
d. changes AC power to DC power