Maker Pro
Maker Pro

Question about power supplies ?

I

isr

Jan 1, 1970
0
I was wondering if someone could hazard a guess as to what sort
of power supply circuit I have. Here are the clues:

- voltage 0-15V
- current 0-3A with current limit facility/dial
- input voltage 230V 50Hz (i.e. Europe system)
- there is a large heat sink with two 2N3055 power T's connected in parallel
- when the voltage is increased above around 6V there is an audiable click
due to the relay inside, see picture
- there are 4 diode bridge circuits, see top left, top right, and two at bottom right,
see picture
- other active components are L7809CV x 2, L7812C, LM741CN,
D313, LM324N, C1008 x 2, TL431C, see picture
- the transformer seems to have 4 outputs, i.e. 2 lots of three wires plus two lots
of 2 wires
- picture of pcb is here : http://www.geocities.com/psuinternals/psu.jpg

I am curious as to how this psu works, and I was hoping someone would
know looking at the above points and save me to try and recreate the
schematic. Also, it seems this circuit does not use one of the more modern
ic's such as the L200C and instead uses fixed regulators such as the L7809 9v
regulator, the L7812 12v regulator, plus 4 op amps in LM324N plus another
741 op amp. Why anyone would want to use a 741 nowadays is a mystory.
Also used is a variable zener diode - TL431C, and 2 bipolar T's - C1008.
 
W

Watson A.Name - Watt Sun, Dark Remover

Jan 1, 1970
0
[snip]
741 op amp. Why anyone would want to use a 741 nowadays is a mystory.

Because they're cheap. Real cheap, and work just fine for DC PSes.
Also used is a variable zener diode - TL431C, and 2 bipolar T's - C1008.

You didn't even give a make or model number.


--
@@F@r@o@m@@O@r@a@n@g@e@@C@o@u@n@t@y@,@@C@a@l@,@@w@h@e@r@e@@
###Got a Question about ELECTRONICS? Check HERE First:###
http://users.pandora.be/educypedia/electronics/databank.htm
My email address is whitelisted. *All* email sent to it
goes directly to the trash unless you add NOSPAM in the
Subject: line with other stuff. alondra101 <at> hotmail.com
Don't be ripped off by the big book dealers. Go to the URL
that will give you a choice and save you money(up to half).
http://www.everybookstore.com You'll be glad you did!
Just when you thought you had all this figured out, the gov't
changed it: http://physics.nist.gov/cuu/Units/binary.html
@@t@h@e@@a@f@f@l@u@e@n@t@@m@e@e@t@@t@h@e@@E@f@f@l@u@e@n@t@@
 
I

isr

Jan 1, 1970
0
Watson A.Name - Watt Sun said:
[snip]
741 op amp. Why anyone would want to use a 741 nowadays is a mystory.

Because they're cheap. Real cheap, and work just fine for DC PSes.
Also used is a variable zener diode - TL431C, and 2 bipolar T's - C1008.

You didn't even give a make or model number.

the make is Tatoo, how this will help you I do not know.
 
L

Luhan Monat

Jan 1, 1970
0
isr said:
I was wondering if someone could hazard a guess as to what sort
of power supply circuit I have.

An old one.
 
Top