test4electricity

Question 1

Test4 electricity

Question 2

Noisey uncontrollable arc that flares from side to side

Answer 2

arc blow

Question 3

This term describes the influence exerted by a magnetic field on neighbouring bodies without physical contact

Answer 3

inductance

Question 4

The fundamental unit of electricity that moves through a conductor when current is flowing

Answer 4

electrons

Question 5

Which term describes the NEMA rating of a welding machine

Answer 5

duty cycle

Question 6

Electrode positive means

Answer 6

reverse polarity

Question 7

Electrons have a

Answer 7

negative charge

Question 8

Which term measures the strength of a current of electricity

Answer 8

amperage

Question 9

What term describes a medium that provides an electrical path for current to flow through

Answer 9

conductor

Question 10

The electron flow theory states that electrons move from

Answer 10

negative to positive

Question 11

What term describes the voltage output of the machine during welding

Answer 11

arc voltage

Question 12

This device in a welding machine is designed to have a certain number of wire turners

Answer 12

coil

Question 13

Main function of this device is to change ac to dc

Answer 13

rectifier

Question 14

Electrode negative is

Answer 14

straight polarity

Question 15

This current flows in one direction only and has either a positive or negative value

Answer 15

direct current

Question 16

Which is graphical illustration that plots the relationship between voltage and amperage output of a welding power source

Answer 16

volt amp curve

Question 17

When no current is flowing in the circuit but the machine is turned on you can measure what

Answer 17

open circuit voltage

Question 18

The speed at which ac changes direction is called the

Answer 18

frequency

Question 19

Three advantages of three-phase systems over single phase systems

Answer 19

constant power more efficient small equipment

Question 20

This welding machine turns AC to DC

Answer 20

transformer rectifier

Question 21

This term describes one complete revolution of the ac alternator

Answer 21

cycle

Question 22

What happens when mechanical energy is applied to a conductor and it moves across the magnetic lines of force in a magnetic field

Answer 22

electrical current is created

Question 23

These machines convert high voltage

Answer 23

low amperage to low amperage high amperage by the use of a primary and secondary coil

Question 24

What does EMF stand for

Answer 24

electromotive force

Question 25

Which term describes the typical sound of an AC transformer welding machine

Answer 25

buzz box

Question 26

What type of welding machine is capable of changing DC to high frequency AC

Answer 26

inverter

Question 27

What is the function of the secondary winding on a transformer welder

Answer 27

to step down the voltage

Question 28

One advantage of the AC transformer welder is freedom from

Answer 28

arc blow

Question 29

What is the purpose of a silicon controlled rectifier

Answer 29

to change AC to DC

Question 30

What is one advantage of an AC-DC transformer rectifier welding machine

Answer 30

you have the choice of polarity

Question 31

A DC motor generator produces what type of welding current

Answer 31

DC

Question 32

How can you change the polarity on a AC alternator welding machine

Answer 32

an AC alternator has no fixed polarity

Question 33

What is one advantage of all transformer welding machines

Answer 33

maintenance costs are lower

Question 34

These welding power sources immediately rectify the incoming AC to DC and then transistors creator a higher frequency AC the higher frequency AC is then rectified to an extremely smooth DC

Answer 34

inverters

Question 35

How did manufactures reduce the size and weight of transformers and generate a significant energy savings over conventional power sources

Answer 35

inverter technology

Question 36

What is an advantage of an inverter welding machine

Answer 36

small lightweight

Question 37

Disadvantage of inverter welding machine

Answer 37

higher initial cost than transformers or rectifiers