Maker Pro
Maker Pro

Powersupply testing

U

Uriah

Jan 1, 1970
0
I have a electronic load powersupply tester and was wondering how you
go about setting it up? For a computer powersupply how would you set
it. Do you set the resistance and for how much? How do you figure
this out. Just measure the inputs on the computer? Does that give
you a correct value? I need to set a 5 volt, 12 volt and 3.3 volt.
Also do you set the amps or watts? So if it says 5 volts 12 amps. I
just need to figure the resistance? and then set it for 12 amps? do I
need to set the watts? Not much in the manual. They assume people
know what they are doing. Also,

I have this powersupply that sometimes doesn't come on and sometimes
does. If it isn't the solder joints how do you track this down?
Anything in particular thing that determines what turns on the PS. It
has a red LED and it will work a few times then not work. I take it to
my bench and it comes on after turning the power on and off and
waiting.

Thanks
Uriah
 
R

Robert Baer

Jan 1, 1970
0
Uriah said:
I have a electronic load powersupply tester and was wondering how you
go about setting it up? For a computer powersupply how would you set
it. Do you set the resistance and for how much? How do you figure
this out. Just measure the inputs on the computer? Does that give
you a correct value? I need to set a 5 volt, 12 volt and 3.3 volt.
Also do you set the amps or watts? So if it says 5 volts 12 amps. I
just need to figure the resistance? and then set it for 12 amps? do I
need to set the watts? Not much in the manual. They assume people
know what they are doing. Also,

I have this powersupply that sometimes doesn't come on and sometimes
does. If it isn't the solder joints how do you track this down?
Anything in particular thing that determines what turns on the PS. It
has a red LED and it will work a few times then not work. I take it to
my bench and it comes on after turning the power on and off and
waiting.

Thanks
Uriah
Computer switching power supplies need a load to operate.
The best way is to load the +5V line with (if i remember correctly)
at least one amp.
Naturally, for proper testing, you need to know the specifications of
the supply being tested.
Again a computer power supply voltages must be within ten percent
except that the 5V must be within 5 percent; if there is a 3.3v output,
i would expect (eg: guess) that it also be within 5 percent.
Now there are noise specifications that are almost universeally
ignored; it is rare that a voltage will be within tolerance but be too
noisy.
What the noise specs aer, i have no idea.
Use your favorite search engine to get details.
 
W

w_tom

Jan 1, 1970
0
5 volts feeding 12 amps means resistance is about .45 ohms. That .45
ohm resistor in power supply tester must be more than 60 watts. So, it
is a fairly larger and warm tester.

Some power supplies require a load to operate; others not. This is a
function unique to each power supply design.

What type of power supply? Computer? Open frame? Bench supply?
Therefore every answer must be based in speculation and assumption.

If you don't even know basic ohms law stuff, then you are probably
not able to understand what you are testing, yet. If you cannot get
calculate same answers, then first learn chapter one in any electrical
basics course. That knowledge would be useful information when using
anything electrical.
 
U

Uriah

Jan 1, 1970
0
I guess I wasn't clear in my original post. My powersupply tester is a
variable load. It provides the load to the powersupply. It is a switch
mode PS. This one is made for a arcade game with 3.3 volts, 12, 5, -5
VDC. They are the same as a computer PS with different connectors. I
am just not
Sure how to set it up? You can set the resistance, current, and watts
on the tester. Of course I can measure PS input on the game pcb, but
using a meter does not
always show the true reactance. Or does it? This is what I am not
sure of. Also do I set the amps and watts or just the amps? I think I
set them for upto the
rated current but do I need to set the watts? So you see where I am a
little confused.
Thanks
Uriah
 
W

w_tom

Jan 1, 1970
0
This sounds like a complex specialty tester costing maybe a thousand
dollars. If adjustable settings are current and watts, then those two
setting automatically define the load for a specific voltage.
Generatlly when connector defines a load to one voltage, then only
current is adjusted - watts is automatically known as part of that
tester design.

Most power supply testers are only resistance loads. If this tester
varies reactance, then this is indeed an expensive electronic tester.
Most power supply testers only contain selectable resistors. For a
predefined voltage, then current is selected, then those resistors are
already sized for the load.
 
M

me

Jan 1, 1970
0
I guess I wasn't clear in my original post. My powersupply tester is a
variable load. It provides the load to the powersupply. It is a switch
mode PS. This one is made for a arcade game with 3.3 volts, 12, 5, -5
VDC. They are the same as a computer PS with different connectors. I
am just not
Sure how to set it up? You can set the resistance, current, and watts
on the tester. Of course I can measure PS input on the game pcb, but
using a meter does not
always show the true reactance. Or does it? This is what I am not
sure of. Also do I set the amps and watts or just the amps? I think I
set them for upto the
rated current but do I need to set the watts? So you see where I am a
little confused.
Thanks
Uriah

find and read the f'n manual.
 
U

Uriah

Jan 1, 1970
0
I have the manual but it is from an Asian company and there is very
little to it as far as examples on how to set it up.

It doesn't have a reactance setting. I just wasn't sure how to factor
that in when setting the resistance or if you need to consider that
when working on an embedded style controller.

It didn't cost that much. Around $450.00?

The adjustables are Resistance, Current, Watts
So I think I need to set the resistance that compares with the board
the PS ususally is plugged into. So I just measure the resistance
with my meter for the 12, 5, -5, 3.3VDC? I get quite a difference.
Is that the correct way for the resistance? I figure you just set the
amps to what ever the PS is rated for. Or at least close to it? Then
there is watts. Do I just leave that alone or set that set the Watts
and leave the amps at 0?

Once I find the unit online I will put a link up to it. I have
emailed and called the people who sold it to me but they never get
back to me, yet.

Thanks
Uriah
 
M

me

Jan 1, 1970
0
I have the manual but it is from an Asian company and there is very
little to it as far as examples on how to set it up.

It doesn't have a reactance setting. I just wasn't sure how to factor
that in when setting the resistance or if you need to consider that
when working on an embedded style controller.

It didn't cost that much. Around $450.00?

The adjustables are Resistance, Current, Watts
So I think I need to set the resistance that compares with the board
the PS ususally is plugged into. So I just measure the resistance
with my meter for the 12, 5, -5, 3.3VDC? I get quite a difference.
Is that the correct way for the resistance? I figure you just set the
amps to what ever the PS is rated for. Or at least close to it? Then
there is watts. Do I just leave that alone or set that set the Watts
and leave the amps at 0?

Once I find the unit online I will put a link up to it. I have
emailed and called the people who sold it to me but they never get
back to me, yet.

Thanks
Uriah

Well, without seeing the actual tester, it is hard to say exactly.
As a guess I'd set the resistance based on what the supply is supposed to
deliver. As an example if it has a 5 and 12 volt output rated for 20 and
12 amps respecively i'd use 5/20=.25 ohms for the 12 volt and 12/12=1 ohm
for the 5 volt. For multi output supplies you might also have to avoid
drawing too much overall power from it. Sometimes there are limits to
the amount of power you can safely dray from some sets of outputs
(usually on the label).
 
J

Josef Hartmut

Jan 1, 1970
0
Uriah said:
I have the manual but it is from an Asian company and there is very
little to it as far as examples on how to set it up.

It doesn't have a reactance setting. I just wasn't sure how to
factor
that in when setting the resistance or if you need to consider that
when working on an embedded style controller.

It didn't cost that much. Around $450.00?

That's not much :)
The adjustables are Resistance, Current, Watts
So I think I need to set the resistance that compares with the board
the PS ususally is plugged into. So I just measure the resistance
with my meter for the 12, 5, -5, 3.3VDC? I get quite a difference.
Is that the correct way for the resistance?

No. You want to measure the peak current during startup on each
channel using a storage scope and then add 5% to it. Use this current
to calculate the resistance using ohm's law.
I figure you just set the
amps to what ever the PS is rated for. Or at least close to it?

A few percent higher, if possible and not hard limited.
Then
there is watts. Do I just leave that alone or set that set the
Watts
and leave the amps at 0?

I don't know the device. I only know you should polish your
electrotechnical basics :)
 
U

Uriah

Jan 1, 1970
0
I just want to thank everyone, (except for the "Read the F**manual"
person:) for the help. I think if you saw the unit you would figure
it out rather quickly. So I tracked it down. I got it at:
http://www.web-tronics.com/3710aprogdce.html
And it was only $350.00 plus shipping. The manual is there online.
Feel free to give up on this. I think I have enough info to know how
to use it.
Thanks again
Russ
 
Top