Transformer power usage

[Richardson]

"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in message news:IFhhm.137271$3m2.93039@newsfe06.iad...

John Fields wrote:

On Thu, 13 Aug 2009 15:09:49 -0400, Jamie
jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:


Rich Grise wrote:

On Thu, 13 Aug 2009 11:49:26 -0400, Jamie wrote:


Scott wrote:



I am curious. Does a transformer draw (considerable) power even with no
load.

I have a cheapo, unregulated 88W 120VAC to 12VAC transformer/timer
(landscape lighting) in which the timer had failed. I also happened to
have a small 120V photocell switch (activates in darkness). When I
removed the timer mechanism, I noted the timer motor was running off of
the 12V side of the transformer, meaning the transformer was always
energized.

With the photocell wired in-line prior to the transformer, there is a
small power draw (<0.25W) during daylight hours, but not what I imagine
the transformer was drawing. Am I correct in my thinking that even an
unloaded transformer would draw considerable wattage?


Yes.


No. Stop misleading the newbies.

Thanks,
Rich



Well, it's true in some parts, it's obvious there is power being drained
while not having any attached device.. There is no such thing as a 100%
power efficient xformer. As you and others can argue the point, it's
just what it is, pointless.

So, yes, the statement is true as far as the poster is concerned.


---
No, it isn't.

Without knowing what the OP means by 'considerable wattage' your answer
is, at best, irresponsible.
---


Going into details of why it happens, isn't what I think
the poster was looking for. Because to be frank about it, I'm sure
the poster does not care as to why, just closure on their assumption.

I don't know what he considers a considerable amount of power, but the
fact that it's using power, makes my statement not false!.


---
No, it doesn't.

What makes your statement true or false isn't the fact that the
transformer isn't 100% efficient, it's what the OP considers to be a
considerable amount of power.

Without knowing that (and he didn't specify what he thought
'considerable' was, your answer is meaningless but will, as Rich pointed
out, confuse the newbie.

JF
Oh well,.

Don't give enough;
Give to much;

What's the difference. Seems that some one can always find
fault.

Oh man, John Fool really isn't helpful is he? He always can't find the right answer, all he said he "What's the difference?" Gosh...

Scott wrote:

I am curious. Does a transformer draw (considerable) power even with no
load.

Scott, the transformer is not supposed to draw power when there is no load, but there is still a small amount of power loss through heat if the primary is too short-circuited. That little transformer draws in milliamp, you won't see it moves your power meter.

 

[John Fields]

On Fri, 14 Aug 2009 16:47:21 -0700, "Richardson" <member@newsguy.com>
wrote:

"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in message news:IFhhm.137271$3m2.93039@newsfe06.iad...
John Fields wrote:

On Thu, 13 Aug 2009 15:09:49 -0400, Jamie
jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:


Rich Grise wrote:

On Thu, 13 Aug 2009 11:49:26 -0400, Jamie wrote:


Scott wrote:



I am curious. Does a transformer draw (considerable) power even with no
load.

I have a cheapo, unregulated 88W 120VAC to 12VAC transformer/timer
(landscape lighting) in which the timer had failed. I also happened to
have a small 120V photocell switch (activates in darkness). When I
removed the timer mechanism, I noted the timer motor was running off of
the 12V side of the transformer, meaning the transformer was always
energized.

With the photocell wired in-line prior to the transformer, there is a
small power draw (<0.25W) during daylight hours, but not what I imagine
the transformer was drawing. Am I correct in my thinking that even an
unloaded transformer would draw considerable wattage?


Yes.


No. Stop misleading the newbies.

Thanks,
Rich



Well, it's true in some parts, it's obvious there is power being drained
while not having any attached device.. There is no such thing as a 100%
power efficient xformer. As you and others can argue the point, it's
just what it is, pointless.

So, yes, the statement is true as far as the poster is concerned.


---
No, it isn't.

Without knowing what the OP means by 'considerable wattage' your answer
is, at best, irresponsible.
---


Going into details of why it happens, isn't what I think
the poster was looking for. Because to be frank about it, I'm sure
the poster does not care as to why, just closure on their assumption.

I don't know what he considers a considerable amount of power, but the
fact that it's using power, makes my statement not false!.


---
No, it doesn't.

What makes your statement true or false isn't the fact that the
transformer isn't 100% efficient, it's what the OP considers to be a
considerable amount of power.

Without knowing that (and he didn't specify what he thought
'considerable' was, your answer is meaningless but will, as Rich pointed
out, confuse the newbie.

JF
Oh well,.

Don't give enough;
Give to much;

What's the difference. Seems that some one can always find
fault.


Oh man, John Fool really isn't helpful is he? He always can't find the right answer,
all he said he "What's the difference?" Gosh...

---
Of course I'm helpful, you just can't see it.
---

Scott wrote:

I am curious. Does a transformer draw (considerable) power even with no
load.

Scott, the transformer is not supposed to draw power when there is no load,
but there is still a small amount of power loss through heat if the primary
is too short-circuited.

---
"If the primary is too short-circuited"?

You poor dumb bastard, you don't even know what you're talking about,
but you're so fucking stupid you don't know that either.
---

That little transformer draws in milliamp,
you won't see it moves your power meter.

---
If you're talking about that thing on the wall with a wheel spinning in
it, that's a watt-hour meter, not a power meter, and it measures energy
consumed.

If you're talking about something that measures milliamperes, that's a
milliammeter, not a power meter.

Oh, and by the way, why don't you set up your newsreader so that it
line-wraps properly?

JF

 

[Speeders & Drunk Drivers]

"John Fields" <jfields@austininstruments.com> wrote in message news:tuhd85110n7m337c63r9tat0ld2l3oe505@4ax.com...

On Fri, 14 Aug 2009 16:47:21 -0700, "Richardson" <member@newsguy.com
wrote:


"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote in message news:IFhhm.137271$3m2.93039@newsfe06.iad...
John Fields wrote:

On Thu, 13 Aug 2009 15:09:49 -0400, Jamie
jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:


Rich Grise wrote:

On Thu, 13 Aug 2009 11:49:26 -0400, Jamie wrote:

Scott wrote:
I am curious. Does a transformer draw (considerable) power even with no
load.

I have a cheapo, unregulated 88W 120VAC to 12VAC transformer/timer
(landscape lighting) in which the timer had failed. I also happened to
have a small 120V photocell switch (activates in darkness). When I
removed the timer mechanism, I noted the timer motor was running off of
the 12V side of the transformer, meaning the transformer was always
energized.

With the photocell wired in-line prior to the transformer, there is a
small power draw (<0.25W) during daylight hours, but not what I imagine
the transformer was drawing. Am I correct in my thinking that even an
unloaded transformer would draw considerable wattage?


Yes.


No. Stop misleading the newbies.

Thanks,
Rich



Well, it's true in some parts, it's obvious there is power being drained
while not having any attached device.. There is no such thing as a 100%
power efficient xformer. As you and others can argue the point, it's
just what it is, pointless.

So, yes, the statement is true as far as the poster is concerned.


---
No, it isn't.

Without knowing what the OP means by 'considerable wattage' your answer
is, at best, irresponsible.
---


Going into details of why it happens, isn't what I think
the poster was looking for. Because to be frank about it, I'm sure
the poster does not care as to why, just closure on their assumption.

I don't know what he considers a considerable amount of power, but the
fact that it's using power, makes my statement not false!.


---
No, it doesn't.

What makes your statement true or false isn't the fact that the
transformer isn't 100% efficient, it's what the OP considers to be a
considerable amount of power.

Without knowing that (and he didn't specify what he thought
'considerable' was, your answer is meaningless but will, as Rich pointed
out, confuse the newbie.

JF
Oh well,.

Don't give enough;
Give to much;

What's the difference. Seems that some one can always find
fault.


Oh man, John Fool really isn't helpful is he? He always can't find the right answer,
all he said he "What's the difference?" Gosh...

---
Of course I'm helpful, you just can't see it.
---

Scott wrote:

I am curious. Does a transformer draw (considerable) power even with no
load.

Scott, the transformer is not supposed to draw power when there is no load,
but there is still a small amount of power loss through heat if the primary
is too short-circuited.

---
"If the primary is too short-circuited"?

You poor dumb bastard, you don't even know what you're talking about,
but you're so fucking stupid you don't know that either.
---

Wow, you really know what you're talking about hugh? Look at your banks joining drop-dead list. You are those banks, because you believe you know what you were talking about heehee.

That little transformer draws in milliamp,
you won't see it moves your power meter.

---
If you're talking about that thing on the wall with a wheel spinning in
it, that's a watt-hour meter, not a power meter, and it measures energy
consumed.

If you're talking about something that measures milliamperes, that's a
milliammeter, not a power meter.

Oh, and by the way, why don't you set up your newsreader so that it
line-wraps properly?

JF

Wow thanks for your funny posts.. bye-bye pussy face my poor John Fool.

 

[John Fields]

On Sat, 15 Aug 2009 13:05:41 -0700, "Speeders & Drunk Drivers are
MURDERERS" <xeton2001@yahoo.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message news:tuhd85110n7m337c63r9tat0ld2l3oe505@4ax.com...
On Fri, 14 Aug 2009 16:47:21 -0700, "Richardson" <member@newsguy.com
wrote:

Scott, the transformer is not supposed to draw power when there is no load,
but there is still a small amount of power loss through heat if the primary
is too short-circuited.

---
"If the primary is too short-circuited"?

You poor dumb bastard, you don't even know what you're talking about,
but you're so fucking stupid you don't know that either.
---

Wow, you really know what you're talking about hugh? Look at your banks joining drop-dead list.
You are those banks, because you believe you know what you were talking about heehee.

---
I don't run a bank, I run a successful consulting firm while all you do
is run your mouth and offer ridiculous advice.
---

That little transformer draws in milliamp,
you won't see it moves your power meter.

---
If you're talking about that thing on the wall with a wheel spinning in
it, that's a watt-hour meter, not a power meter, and it measures energy
consumed.

If you're talking about something that measures milliamperes, that's a
milliammeter, not a power meter.

Oh, and by the way, why don't you set up your newsreader so that it
line-wraps properly?

JF



Wow thanks for your funny posts.. bye-bye pussy face my poor John Fool.

---
If only it were true!

But you'll be back...

You just can't seem to stay away from USENET and the childish, perverted
sexual references you use, can you?

Well, at least you've got a place where you can blow off steam without
going postal while learning what a piece of shit you are, and that's a
good thing.

Come on back whenever you feel you need to get your fair share of abuse.
JF

 

[Scott]

Scott wrote:

John Fields wrote:
On Thu, 13 Aug 2009 15:09:49 -0400, Jamie
jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:

Rich Grise wrote:
On Thu, 13 Aug 2009 11:49:26 -0400, Jamie wrote:

Scott wrote:


I am curious. Does a transformer draw (considerable) power even
with no load.

I have a cheapo, unregulated 88W 120VAC to 12VAC transformer/timer
(landscape lighting) in which the timer had failed. I also
happened to have a small 120V photocell switch (activates in
darkness). When I removed the timer mechanism, I noted the timer
motor was running off of the 12V side of the transformer, meaning
the transformer was always energized.

With the photocell wired in-line prior to the transformer, there
is a small power draw (<0.25W) during daylight hours, but not what
I imagine the transformer was drawing. Am I correct in my
thinking that even an unloaded transformer would draw considerable
wattage?

Yes.

No. Stop misleading the newbies.

Thanks,
Rich


Well, it's true in some parts, it's obvious there is power being drained
while not having any attached device.. There is no such thing as a 100%
power efficient xformer. As you and others can argue the point, it's
just what it is, pointless.

So, yes, the statement is true as far as the poster is concerned.

---
No, it isn't.

Without knowing what the OP means by 'considerable wattage' your answer
is, at best, irresponsible.
---

Going into details of why it happens, isn't what I think
the poster was looking for. Because to be frank about it, I'm sure
the poster does not care as to why, just closure on their assumption.

I don't know what he considers a considerable amount of power, but the
fact that it's using power, makes my statement not false!.

---
No, it doesn't.

What makes your statement true or false isn't the fact that the
transformer isn't 100% efficient, it's what the OP considers to be a
considerable amount of power.

Without knowing that (and he didn't specify what he thought
'considerable' was, your answer is meaningless but will, as Rich pointed
out, confuse the newbie.

JF

Thank you for the continued response. Actually I am interested in the
'why' as well as a definitive 'yeah' or 'neigh', despite my lack of
details and tentative grasp of electronics. By my simplistic thinking,
tying each end of a wire to AC mains should draw current and use it up
as resistive heat. I believe I am underestimating the function of the
inductor of the transformer's primary.

I am sorry I did not measure the current while it was powered but
unloaded. I will take some measurements this weekend for my own
curiosity. I am fairly certain what I saw was simply high resistive
losses due to the aging steel core.

For arguements sake, I would consider "Considerable" to be 50% or more
of the loaded wattage.

Thanks!
Scott

Update: Transformer did fail within a week of light use (20W). The

(plastic) supports for the buses adjacent to the primary winding were
reduced to a crater of black powder and soot. All nearby wiring had
heat damage to the insulation, with the whites completely bare and
crispy for the last inch to the bus. Whites seem to have melted from
the inside.

Thank you all for your advice. I do understand now that an unloaded
transformer does not consume considerable wattage. Minimal losses less
than 5% are normal to typical transformers.

Time to buy another transformer.
Thanks!
Scott

 

[Don Klipstein]

In art. <4a8574de$0$4940$9a6e19ea@unlimited.newshosting.com>, Scott wrote:

Phil Allison wrote:
"Scott"

For arguements sake, I would consider "Considerable" to be 50% or more of
the loaded wattage.

** FYI pal - the un-loaded power loss of a 300VA toroidal mains
transformer is about 3 to 4 watts.

The un-loaded power loss of a typical 300VA E-core type is about 6 to 8
watts.

Bored with trolling yet ??

.... Phil

Phil,
Thank you for the details. This is the kind of information I was hoping
to find.

Only trolling for info,
Scott

Please beware of how P. A. in Australia gets to be a Usenet irritant
from Australia, possibly arguably 2nd-place to Auastralia's worst
sub-troll who got a FAQ onto himself (only mildly-slightly out-of-date if
over 10 years old), whose primary sub-troling name is "Rod Speed".

I sometimes wonder if P.A. and R.S. are both "mental patients" at the
same psychiatric ward at some locality in Australia.

I invite either of these to exercize emotional maturity achiecving
growth to extent of posting anything indicating significant growth of
emotional maturity past the juvenile postings typical of both even so
far in 2009.

Best Regards with Goog Hopes,

- Don Klipstein (Jr) (don@misty.com)