ch8_PowerSupplies Flashcards
What is voltage?
The pressure of electricity measured in Volts (V)
What is Amperage?
The amount of electricity moving past a certain point on a wire. Measured in Amps (a)
What is Wattage?
The amount of amps and volts needed to function a device. Measured in Watts (W)
What is Direct Current (DC)?
The Electrons move in one direction in a continous circuit
What is Alternating Current?
The electrons will alternate directions.
What is the difference between AC and DC
AC moves farther, DC is used by most devices
What is a continuity test do?
Checks if the electrons can move from one end to ther other end of the wire.
What does a resistance test show
An inifinite resistance means the wire is broken. a Good wire will show no resistance.
How can you determine an adapter is right for the device?
- Amps, Volts, and Polarity must match.
- If the volts are too high it could burn out the device.
What does purpose does a surge suppressor serve
It absorbs the electricity that is not used.
- Must have UL 1449 rating
- Minimum 2000 joules
What is clamping voltage
during an overvoltage the suppressor will bring it down to a manageable level.
What is power conditioning
Can filter out RMI and EMI
What is a UPS and what purpose does it serve
Use of a battery during a power sag.
- Watts = how much power they can supply
- Volt-Amps = how much power it could supply if it was provided in a perfect way
What is an Online UPS?
Constantly powered through the battery
What is a standby UPS?
Devices will be powered by battery when voltage drops below 80-90 volts
What is Line interactive UPS?
Handles moderate sags and surges without needing to switch to battery.
Waht voltages does the PSU supply
3,3 V, 5V, 12V (important ones)
What is the common PSU size?
150mm x 140 mm x 86 mm
What feature does a ATX power supply have
Soft power is always feeding 5 v to the motherborad to prevent the user from shutting the computer down before its ready to be shut down
What features do the ATX 12V 1.3 have
An additional 4 pin 12v connector is needed by intel cpu
What makes the EPS12V unique?
A 24 pin connector and an aux connector and a unique 8 pin connector
The PSU is not interchangeable
What makes a Rails PSU unique
Over current protection will shut down the PSU if it goes beyond its cap.
Single Rail - monitors all pathways
Multi Rail - Monitor for each pathway
What makes ATX12V2.0 Unique
The 24 pin connector is interchangeable with a 20 pin connector, but may not alwasy be compatible
- 2 12 V rails are required if psu is higher than 230 W
- CPU uses a 4 pin connector, but some motherboards may use a 8 pin connector
- PCIe devices use a 6 or 8 pin connector
What PSU is designed for SFF
Mini or Micro ATX
What PSU is designed for low profile atx systems
TFX12V
What PSU is designed for flex atx systems
SFX12V
What PSU is designed for micro BTX systems
CFX12V
What PSU is designed for low profile BTX systems
LFX12V
What is harmonics
The electrical phenomena of current only flowing when fully pushed or pulled - cause of electrical buzzing
What is the purpose of Power Factor Correction
Smooths out electrical current before being passed to the main circuitry
What are the three efficiency ratings?
Bronze = 85% Gold = 90% Platinum = 94%
Where does the remaing percentage of efficiency get lost too
Heat
