No Clue Newby transformer question.
 

Hi, I`m a complete electrics novice and at the moment every thing I
try doesn`t work. Even down to shorting a PC`s Power Supply Unit so
that it`ll work without being connected to the motherboard, which
concists of "simply" grounding the power wire with a paperclip,
would`nt work for me. What I realy want to know, though, is; in what
order do power supply-transformer-mains supply, go. I`m pretty sure
that the mains supply (230v) goes straight to the transformer and then
from the transformer to the powersupply (PCB with resistors, led`s
etc)and from the powersupply to the amp/radio/computer......
I have seen schematic drawings for this but I don`t understand them
and I have looked all over for a diagram or photo but can`t find one.
I am just looking for a plain english explination coupled with some
photographs. Any help apreceiated.
Thanks.
Dave.

A transformer either converts the voltage up or down or isolates the power
supply from the AC line.

So power transformers are hooked directly to the AC line yes
After that comes the "circuit" of the power supply with things like
A bridge rectifier, a BIG capacitor or capacitors, a voltage regulator etc
etc.
Be VERY careful screwing with 220. It can kill you so fast it's not funny.

"Dave." wrote in message
om...
Hi, I`m a complete electrics novice and at the moment every thing I
try doesn`t work. Even down to shorting a PC`s Power Supply Unit so
that it`ll work without being connected to the motherboard, which
concists of "simply" grounding the power wire with a paperclip,
would`nt work for me. What I realy want to know, though, is; in what
order do power supply-transformer-mains supply, go. I`m pretty sure
that the mains supply (230v) goes straight to the transformer and then
from the transformer to the powersupply (PCB with resistors, led`s
etc)and from the powersupply to the amp/radio/computer......
I have seen schematic drawings for this but I don`t understand them
and I have looked all over for a diagram or photo but can`t find one.
I am just looking for a plain english explination coupled with some
photographs. Any help apreceiated.
Thanks.
Dave.

"blah" wrote in message news:vLR4d.40347$wV.6053@attbi_s54...
A transformer either converts the voltage up or down or isolates the power
supply from the AC line.

So power transformers are hooked directly to the AC line yes
After that comes the "circuit" of the power supply with things like
A bridge rectifier, a BIG capacitor or capacitors, a voltage regulator etc
etc.
Be VERY careful screwing with 220. It can kill you so fast it's not funny.


I believe today's computers don't use transformers anymore. They use an
electronic power supply instead.


"Dave." wrote in message
om...
Hi, I`m a complete electrics novice and at the moment every thing I
try doesn`t work. Even down to shorting a PC`s Power Supply Unit so
that it`ll work without being connected to the motherboard, which
concists of "simply" grounding the power wire with a paperclip,
would`nt work for me. What I realy want to know, though, is; in what
order do power supply-transformer-mains supply, go. I`m pretty sure
that the mains supply (230v) goes straight to the transformer and then
from the transformer to the powersupply (PCB with resistors, led`s
etc)and from the powersupply to the amp/radio/computer......
I have seen schematic drawings for this but I don`t understand them
and I have looked all over for a diagram or photo but can`t find one.
I am just looking for a plain english explination coupled with some
photographs. Any help apreceiated.
Thanks.
Dave.

If you are talking about getting a PC Power supply to switch on (for hobby
reasons or what [ie a cheap psu]) yo uwill need to do the following:

if an ATX PSU, short pin 14 of the psu connecto to GND (one of the black
leads). YOu may also need a dummy load between the +5V (Red cable) and GND
(Black cable). Usually PC PSUs are switched mode powersupplies and require
500mA minimum loading for them to work correctly. This means you'll need
5V/.5A = 10ohms (wire wound since it'll be dissapating 2.5Watts).





"Dave." wrote in message
om...
Hi, I`m a complete electrics novice and at the moment every thing I
try doesn`t work. Even down to shorting a PC`s Power Supply Unit so
that it`ll work without being connected to the motherboard, which
concists of "simply" grounding the power wire with a paperclip,
would`nt work for me. What I realy want to know, though, is; in what
order do power supply-transformer-mains supply, go. I`m pretty sure
that the mains supply (230v) goes straight to the transformer and then
from the transformer to the powersupply (PCB with resistors, led`s
etc)and from the powersupply to the amp/radio/computer......
I have seen schematic drawings for this but I don`t understand them
and I have looked all over for a diagram or photo but can`t find one.
I am just looking for a plain english explination coupled with some
photographs. Any help apreceiated.
Thanks.
Dave.