Ac Dc Flashcards
What type of force is Voltage?
is electrical force
• Current is electron flow…
through a wire
Voltage is measured in?
– Measured in amperage
• Current and amperage are…
often used interchangeably
• So, volts push what?
– The force on the electrons…
– The amount of electron flow…
electrons through conductors
is in volts
flow in amps
Direct Current moves in?
From?
one direction
– Negative to positive
Direct Current Can be produced through what reaction?
produced through chemical reaction
– A battery’s electrolyte produces what?
produces electrons
– Negative end gives away what?
gives away electrons
– Positive end collects what?
collects electrons
Alternating Current (AC) is produced by what?
• Does it move in one direction?
by a generator
Yea
Alternating Current (AC)
• Produced by a generator
Cycles and Frequency
• Cycle is what?
– One complete electrical alternation
•
Frequency is what?
– Number of cycles in a second
• Frequency designations:
What is frequency measured in?
Hertz (Hz)
Generating Alternating Current (AC) you need to pass a…
Pass a conductor through a magnetic field
Expressing AC with a Sine Wave
A sine wave shows
– First
– Then reverses
how alternating current
flows
in one direction,
to flow in the opposite direction
Expressing AC with a Sine Wave
– First in one direction,
– Then reverses to flow in the opposite direction
Effective Voltage
• Alternating current sine wave:
Starts at what number?
Then it…
Then returns to?
– Starts at 0,
– Reaches a peak (maximum),
Returns to 0
Effective Voltage
• Alternating current sine wave:
What is peak voltage at?
• “Peak voltage” at 90° (electrical degrees)
Effective Voltage
• Alternating current sine wave:
What is effective voltage at?
• “Effective voltage” (0.707 x peak voltage)
Effective Voltage
• Alternating current sine wave:
• “Effective voltage” (0.707 x peak voltage)
Generating Three Phase Alternating Current
• Generated by passing three conductors…
through a magnetic field
Generating Three Phase Alternating Current
• Three-phase, 3-Phase, and 3Ø
Inductance:
Is the out of phase condition between what two things?
– between voltage and amperage
Reactance:
It is what the resistance voltage encounters when
– when it changes flow
• Inductive reactance:
–a combination of what two things?
What is it nessecary for?
A combination of inductance and reactance
– starting and running of an induction motor
Capacitive Reactance
Capacitors can create an out-of-phase
condition between what two things?
• between voltage and amperage
Capacitive Reactance
The voltage lags
That is how capacitors
– behind the amperage (current)
• increase starting
torque
