I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

Daniele

In article
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

Yes
--
fred
BBC3, ITV2/3/4, channels going to the DOGs

In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

Why not put a nominal load across it and try it under realistic
conditions
--
geoff

In an earlier contribution to this discussion,
D.M. Procida wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V),
which says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces
9.38V without load.

Does that sound like it's a regulated PSU?

Daniele


This may not help if you haven't got anything to compare it with, but ISTR
that the dimensions of the output connector are different depending on
whether or not it's regulated. Assuming that it's got a concentric-type
cylindrical connector, I think that regulated supplies have a bigger hole in
the middle - the rationale being that devices requiring a regulated supply
have fatter central pins in their connectors, to prevent an unregulated
supply from being connected.

I'm sure that someone will correct me if this is wrong!

But the fact that it says "IC UNIVERSAL REGULATOR" on it, and the fact that
the no-load output is only 9.4v suggests to me that it *is* regulated.
Unregulated 9v supplies often deliver 12 or 13 volts on no load.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

D.M. Procida laid this down on his screen :
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

Not really, unless the thing (switch/control/?)you are setting the
voltage with is out of calibration.

Apply a small percentage of the full load and measure the voltage -
repeat with a full rated load and the voltage should be similar.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

On Sun, 03 Jan 2010 21:31:19 +0000, D.M. Procida wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage is
accurate. What it means is that the voltage won't change (much) with
varying load. In reality it will sag a bit, so 9v sounds very likely.

--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info
Filtering everything posted from googlegroups to kill spam.

mick wrote:

On Sun, 03 Jan 2010 21:31:19 +0000, D.M. Procida wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage is
accurate. What it means is that the voltage won't change (much) with
varying load. In reality it will sag a bit, so 9v sounds very likely.

Thanks for all the various replies.

How different from the loaded output would the unloaded voltage need to
be before one could reasonably judge such a PSU to be unregulated?

Daniele

D.M. Procida wrote:
wrote:

On Sun, 03 Jan 2010 21:31:19 +0000, D.M. Procida wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage is
accurate. What it means is that the voltage won't change (much) with
varying load. In reality it will sag a bit, so 9v sounds very likely.

Thanks for all the various replies.

How different from the loaded output would the unloaded voltage need to
be before one could reasonably judge such a PSU to be unregulated?

Daniele
It all depends on the design but I'd expect around 10% change when the
load is varied from 10% to 100% of full load if it was an UN-regulated
supply.
A quality regulated supply would vary less than 1% over a similar range
of loads.

Bob

geoff wrote:
In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

A cheap and nasty volt meter will produce the same fault.

Why not put a nominal load across it and try it under realistic conditions

Without an accurate volt meter, this will tell the op nothing.

Dave

In an earlier contribution to this discussion,
D.M. Procida wrote:


How different from the loaded output would the unloaded voltage need
to be before one could reasonably judge such a PSU to be unregulated?

Daniele

Depends on the quality! I would expect a regulated supply to control the
voltage within a couple of percent over its rated current range, whereas an
unregulated supply may be several tens of percent over the nominal voltage
at no load - but should be close to the nominal voltage at full load. I'm
guessing a bit with the actual figures - but the thing is, they're an order
of magnitude apart!

A regulated supply will have some sort of feed-back loop, to maintain a
more-or-less constant voltage regardless of load - whereas an unregulated
supply won't, so it's voltage will fall as the load increases.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

In message , Dave
writes
geoff wrote:
In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

A cheap and nasty volt meter will produce the same fault.

Even cheap and nasty voltmeters are accurate to 1% nowadays


Why not put a nominal load across it and try it under realistic conditions

Without an accurate volt meter, this will tell the op nothing.

Dave

--
geoff

In message , Bob Minchin
writes
D.M. Procida wrote:
wrote:

On Sun, 03 Jan 2010 21:31:19 +0000, D.M. Procida wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage is
accurate. What it means is that the voltage won't change (much) with
varying load. In reality it will sag a bit, so 9v sounds very likely.

Thanks for all the various replies.

How different from the loaded output would the unloaded voltage need to
be before one could reasonably judge such a PSU to be unregulated?

Daniele
It all depends on the design but I'd expect around 10% change when the
load is varied from 10% to 100% of full load if it was an UN-regulated
supply.
A quality regulated supply would vary less than 1% over a similar range
of loads.

So he is ~5% off

a semi-regulated supply then ...

--
geoff

geoff wrote:
In message , Dave
writes
geoff wrote:
In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

A cheap and nasty volt meter will produce the same fault.

Even cheap and nasty voltmeters are accurate to 1% nowadays

It did cross my mind, while typing that, to do a test with my cheap and
nasty voltmeters in the morning, using my calibrated one. :-)


Dave

On Jan 3, 8:31*pm, Dave wrote:
geoff wrote:
In message , Dave
writes
geoff wrote:
In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

A cheap and nasty volt meter will produce the same fault.

Even cheap and nasty voltmeters are accurate to 1% nowadays

It did cross my mind, while typing that, to do a test with my cheap and
nasty voltmeters in the morning, using my calibrated one. *:-)

Dave- Hide quoted text -

- Show quoted text -

So at one setting; 9.38 compared to 9 = a 4.22% variation!
Would that everything else in this world be that precise?
And 'regulated' most likely means that it will not vary more than a
certain amount over a pre-designed and stated range of loads and
voltage settings.
In that case anything that does not vary by more than 5% is, for most
practical purposes, pretty accurate!
An amount of 0.38 volts 'out of wack' at 9 volts is unremarkable.
Unless it is laboratory work; in which case the use of highly accurate
measuring devices is indicated.

On Sun, 03 Jan 2010 22:58:13 +0000, Dave wrote:

geoff wrote:
In message
,
D.M. Procida writes
I have an adjustable PSU with a wide range of voltages (1.5-12V),
which says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces
9.38V without load.

Does that sound like it's a regulated PSU?

A cheap and nasty psu and you expect it to be that accurate offload

A cheap and nasty volt meter will produce the same fault.

Why not put a nominal load across it and try it under realistic
conditions

Without an accurate volt meter, this will tell the op nothing.



It will. It will show whether the supply is regulated or not. Putting
about 10% base load on then adding a further 50% load should give
virtually no change in terminal voltage for a regulated supply. Only the
repeat accuracy of the voltmeter is important.

A lot of cheap-n-nasty digital instruments are well within 1% tolerance
now - particularly on DC voltage ranges where 0.5% or better is common
(but you can't always trust what it says on the box, of course!).

--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info
Filtering everything posted from googlegroups to kill spam.

mick wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage
is accurate. What it means is that the voltage won't change (much) with
varying load. In reality it will sag a bit, so 9v sounds very likely.

If it contains a regulator IC and it's also switchable between various
voltages, that sounds like an LM713 (or similar) with a switched chain
of divider resistors. If these resistors are selected from standard
values with say 5% tolerance, there are bound to be small deviations
from the nominal output voltages. Even so, the selected output voltage
should be quite well regulated against changing loads... until it hits
the limitations of the transformer and smoothing capacitor.


--
Ian White

Ian White wrote:
mick wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage
is accurate. What it means is that the voltage won't change (much)
with varying load. In reality it will sag a bit, so 9v sounds very
likely.

If it contains a regulator IC and it's also switchable between various
voltages, that sounds like an LM713 (or similar) with a switched chain
of divider resistors. If these resistors are selected from standard
values with say 5% tolerance, there are bound to be small deviations
from the nominal output voltages. Even so, the selected output voltage
should be quite well regulated against changing loads... until it hits
the limitations of the transformer and smoothing capacitor.


or even an LM317!

Bob

Bob Minchin wrote:
Ian White wrote:
mick wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V), which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage
is accurate. What it means is that the voltage won't change (much)
with varying load. In reality it will sag a bit, so 9v sounds very
likely.

If it contains a regulator IC and it's also switchable between various
voltages, that sounds like an LM713 (or similar) with a switched chain
of divider resistors. If these resistors are selected from standard
values with say 5% tolerance, there are bound to be small deviations
from the nominal output voltages. Even so, the selected output voltage
should be quite well regulated against changing loads... until it hits
the limitations of the transformer and smoothing capacitor.


or even an LM317!


Oops, sorry - my 317s and 723s are starting to interbreed in the
component drawer.



--
Ian White

Ian White wrote in message
...
Bob Minchin wrote:
Ian White wrote:
mick wrote:

I have an adjustable PSU with a wide range of voltages (1.5-12V),
which
says "IC UNIVERSAL REGULATOR" on it. When set to 9V it produces 9.38V
without load.

Does that sound like it's a regulated PSU?



Almost certainly. If it had been unregulated you would have probably
measured well over 10v off load.

Just because the supply is regulated it doesn't mean that the voltage
is accurate. What it means is that the voltage won't change (much)
with varying load. In reality it will sag a bit, so 9v sounds very
likely.

If it contains a regulator IC and it's also switchable between various
voltages, that sounds like an LM713 (or similar) with a switched chain
of divider resistors. If these resistors are selected from standard
values with say 5% tolerance, there are bound to be small deviations
from the nominal output voltages. Even so, the selected output voltage
should be quite well regulated against changing loads... until it hits
the limitations of the transformer and smoothing capacitor.


or even an LM317!


Oops, sorry - my 317s and 723s are starting to interbreed in the
component drawer.

Going off topic a little, over the years I've had a few switched mode power
supplies in pc's go tits up. If money (and space) was no object would one
actually be better of using a linear voltage regulator? Or is it a case of
cheap components in the pc supplies.

Jim



--
Ian White

In article ,
"Jim Ingram" writes:
Going off topic a little, over the years I've had a few switched mode power
supplies in pc's go tits up. If money (and space) was no object would one
actually be better of using a linear voltage regulator?

Better off in what respect?

Or is it a case of
cheap components in the pc supplies.

I've only had one PC power supply die on me, out of perhaps 20+
that I've used. Ironically, it was a more expensive one. My
oldest one is 18 or 19 years old (200W in a 486 system), and
still works fine, but not used for last 5 years other than just
occasionally. It was running 24x7 for around 10 years, and
probably 18x7 for the remainder.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Mon, 04 Jan 2010 21:40:11 +0000, Jim Ingram wrote:
Going off topic a little, over the years I've had a few switched mode power
supplies in pc's go tits up. If money (and space) was no object would one
actually be better of using a linear voltage regulator? Or is it a case of
cheap components in the pc supplies.

Most PC PSUs have very small fans and zero filtering - airflow isn't the
best when new, and they quickly choke with dust, overheat and die. Yes,
the components can be pretty marginal, too. A good many of them have
little in the way of overload protection (and maybe none at all on the
rails other than +5V).