Chapter 7: Power Supplies (A+ Study Notes)

A+

Study Notebook

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You can find my complete study notes in Google Docs format below: https://docs.google.com/document/d/1zcKLWfsns1tqzmXtVRJbcd9NqfaEcjifgIo-oJIbEgc/edit?usp=sharing

References:
M. MEYERS, 2019.  CompTIA A+ All-in-One Exam Guide. 10th ed.

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Chapter 7: Power Supplies

           Voltage (V) = Water Pressure

·         Higher Voltage = Higher water pressure

            Amperage (Amps) = Amount of water coming out from the hose

Watts (Volts x Amps) - work accomplished

Ohms = resistance

Current = DC & AC

DC (Direct Current) - constant power in one direction. Plus to minus. Continuous circuit. 

- Over the distance it loses its Voltage.

- Most electronic devices use this 

AC (Alternating Current) - power alternates back and forth in a circuit. 

·         Energy supply companies use this

            Multimeter (DMM - Digital Multimeter) 

·         Types of electrical tests:

·         Continuity

·         Tests whether electrons can flow from one end of a wire to the other end

·         You can use this setting to determine if the fuse is good or to check for breaks in wires

·         Resistance

·         A broken wire or fuse will show infinite resistance, while a good wire or fuse will show no resistance.

·         DC Voltage (VDC)

·         AC Voltage (VAC)

·         Testing AC power:

1.    Check Live/Hot outputs 115V (or 220 etc. depending on the part of the world you are in)

2.    Neutral connects to ground (0V Output)

3.    Ground connects to ground (0V) 

• Motherboard use a 20- or 24-pin P1 power connector. With some motherboards requiring extra 4-, 6-, 8--pin connectors to supply extra power.

• Molex Connectors supply 5V and 12V Current for fans and older drives

• Mini Connector / Berg Connector - supply 5V and 12V to peripherals.

• SATA Power Connectors

• ATX12V 1.3  - 4-pin motherboard power connector also called P4 power connector, that provides more 12-V power to assist the 20/24-pin P1 motherboard power connector.

• It also introduced a 6-pin auxiliary connector—commonly called an AUX connector—to supply increased 3.3- and 5-V current to the motherboard
• EPS12V - 24-pin, with AUX connector, and a unique 8-pin connector. Just to Supply enough power and stability for server motherboards.
• PCI-E - 6-pin or 8-pin (2 pins are detachable for extra power)