Basic Principles Of Electricity Flashcards
What us another name for voltage?
Electromotive force (EMF) or potential difference
Electrical resistance is measured in what?
Ohms “Ω” ohms is the Greek letter for Omega
Electrical resistance is measured in what?
Ohms “Ω” ohms is the Greek letter for Omega
In a water system, there must be pressure If you want to maintain water flow against the resistance of the pipes. In an electrical circuit, you need a ______ to maintain current flow ______ against the resistance ____ of the wire. The higher the resistance, the greater the voltage required to maintain the current. This relationship between voltage and resistance is expressed in ohms law.
Voltage, amperes, ohms
What is the equation for ohms law?
What is the equation to find wattage?
E=I×R
W=A×X
E=voltage
I= current in amperes
R= resistance in ohms
W= Watts A= Amps V= Volts
Generally, the maximum voltage loss allowed between the welding power source and the electrode is _____
4 V
Explain electromagnetism
If a conductor moves through a magnetic field or a magnetic field moves across a conductor, an electric current will be created or “induced” in the conductor.
All devices that convert mechanical energy into electrical energy work on this basic principle, which is called “Faradays law.” In a generator, the conductor moves through a magnetic field. In an alternator, the magnetic field moves across the conductor. The principle is the same.
When an electrical current flows through a conductor, a magnetic field is produced around the conductor. The conductor becomes an electromagnet.
Transformers take high main supply voltages ______ and lower them to usable welding voltages _____ using the principle of induction
220v to 575v, 18v to 36v
What are the coils in a transformer called? When the primary coil has more turns the the secondary coil what is this called and vis versa?
Windings, step-up transformer and step-down
What are the coils in a transformer called? When the primary coil has more turns the the secondary coil what is this called and vis versa?
Windings, step-up transformer and step-down
A welding transformer takes high-voltage, low-amperage input and transforms it to low- voltage high-amparage
.
What is the small electronic device in a Rectifier that changes alternating current to direct current?
Diode
Explain what an inverter is
It converts DC current into AC current at high frequency. Inverters coupled with transformers can be made to produce almost any form of electrical current desired