2. A+ certification training: Electricity/Power Supply

3. Electricity for Computers 8Electric Outlet in Walls: AC,110-120 Volts 8Motherboard Uses DC,+3,-3,+5,-5,+12,-12 8What’s the Solution?

4. THE POWER SUPPLY! 8Changes 110-120 Volts to +-5,+-12 8Changes AC to DC Wall outlet GROUND HOT NEUTRAL

5. SYMBOL FOR GROUND

6. REVIEW OF TERMS 8VOLTS- PRESSURE IN A CIRCUIT 8OHMS- A CONDUCTORS RESISTANCE 8WATTS- POWER IN A CIRCUIT 8AMPS- A CURRENTS STRENGTH 8CONTINUITY- A COMPLETE CIRCUIT

7. THREE PARTS OF A POWER SUPPLY  SWITCHING NETWORK  TRANSFORMER  VOLTAGE REGULATOR

8. SWITCHING NETWORK CLEANS AND CONVERTS THE “IRREGULAR” INPUT AC INTO “REGULAR” DC

9. TRANSFORMER TAKES THE “REGULAR DC 120 VOLT” INTO SEPARATE 12 AND 5 VOLT AC CIRCUITS

10. VOLTAGE REGULATOR _CONVERTS AC BACK TO DC _REGULATES VOLTAGE TO CONSTANT LEVEL _MONITORS AMOUNT OF CURRENT BEING USED BY COMPUTER

11. PARTS OF THE SWITCHING NETWORK 8FUSES-GLASS TUBE, BURNS WHEN TOO MUCH CURRENT FLOWS 8CAPACITORS-LOOKS LIKE BATTERIES, EVEN OUT CURRENT FLOW 8DIODES- KEEPS CURRENT IN 1 DIRECTION 8RECTIFIERS- MADE UP OF DIODES, PRODUCE HALF WAVE AND FULL WAVE RECTIFICATION 8TRANSISTORS-CONVERTS DC INTO “SQUARE” WAVES

12. PARTS OF THE TRANSFORMER CONSIST OF ONLY ONE DEVICE! THE TRANSFORMER ITSELF! IT CONSIST OF 2 COILS WHICH “STEP DOWN” OR REDUCE THE VOLTAGE DOWN TO 5 AND 12 VOLTS

13. PARTS OF THE VOLOTAGE REGULATOR 8RECTIFIER-MAKE AC BACK INTO DC 8CAPACITORS-SMOOTH OUT AC RIPPLES LEFT INTO SMOOTH DC 8COILS- FILTERS OUT AC

14. ESD- ELECTORSTATIC DISCHARGE 8AS LITTLE AS 10 TO 30 VOLTS CAN DESTROY COMPONENTS ON A MOTHERBOARD! 8YOU CAN ONLY FEEL VOLTAGE OF 2000 VOLTS OR GREATER! 8CMOS CHIP MOST SUCCEPTIBLE TO ESD

15. PREVENTING ESD 8USE ANTI STATIC BAGS FOR COMPUTER COMPONENTS 8USE ANTI STATIC WRIST BAND WHEN WORKING ON PC’S AND GROUND YOURSELF OF MAT OR PC FRAME 8STAY AWAY FROM MONITORS WHEN WEARING THIS, THEY HAVE 20,000 VOLTS WHICH COULD KILL YOU!

16. POWER SUPPLY USE MOLEX CONNECTORS 8P8 AND P9’S- USED ON AT MOTHERBOARDS. BLACK WIRE FROM P8 HAS TO LINE UP BESIDE BLACK WIRE FROM P9 8THE MOLEX ON THE ATX IS NOT A P8 OR P9 AND HAS BLACK WIRES ALREADY AUTOMATICLY LINED UP

17. MOLEX CONNECTORS WIRE COLORS 5 DC GROUND 12 DC

18. POWER SUPPLY FACTS 8USE 200-230 WATTS 8BREAK DOWN MORE THAN ANY OTHER PART BESIDES FLOPPY DRIVES 8WHEN HAVING PROBLEMS CHECK: 8ALL CONECTIONS 8FAN 8FUSE

19. CLUES IT’S A POWER SUPPLY PROBLEM 8FREQUENT LOCKING UP WHEN POWERING ON COMPUTER 8OCASIONAL AND DIFFERENT ERROR CODES WHEN BOOTING UP 8FREQUENT LOCKING UP