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Power Pole Transformer is too small
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olds...@tubes.com
Feb 19, 2017, 2:33:12 PM2/19/17
to
This is slightly off topic....
I live on a farm, and have a main disconnect switch on the meter pole,
rated at 400A. That feeds 3 buildings (house, garage, and barn) each has
100A main breakers. It also feeds an old 60A fuse panel in a shed. (yea,
that is still fuses but all it does in run a few lights, so I never
changed it).
This is mostly just my home, but I do a little "hobby farming". So my
electrical needs are small. But this was once a large working farm with
large power users, such as huge 240V motors that ran grain dryers on
grain bins.
Anyhow, the pole transformer has been there for ages, and I just noticed
that it's rated at 15KVA. 15KVA is only 62.5 Amps at 240V. (Or 125A at
120V).
Why would the power company install a transformer so under rated?
-OR- Do they rate those transformers in a different manner?
Like I said, it works for my needs, but in winter, I run several
livestock tank heaters and I tell when they kick on by a very slight
momentary (slight) dimming of my lights. (They are rated at either 500W
or 1000W, but there are 9 of them).
From what I am seeing, those transformers are all under rated. A friends
house has 200A service and his transformer is only 8KVA.
I live on a farm, and have a main disconnect switch on the meter pole,
rated at 400A. That feeds 3 buildings (house, garage, and barn) each has
100A main breakers. It also feeds an old 60A fuse panel in a shed. (yea,
that is still fuses but all it does in run a few lights, so I never
changed it).
This is mostly just my home, but I do a little "hobby farming". So my
electrical needs are small. But this was once a large working farm with
large power users, such as huge 240V motors that ran grain dryers on
grain bins.
Anyhow, the pole transformer has been there for ages, and I just noticed
that it's rated at 15KVA. 15KVA is only 62.5 Amps at 240V. (Or 125A at
120V).
Why would the power company install a transformer so under rated?
-OR- Do they rate those transformers in a different manner?
Like I said, it works for my needs, but in winter, I run several
livestock tank heaters and I tell when they kick on by a very slight
momentary (slight) dimming of my lights. (They are rated at either 500W
or 1000W, but there are 9 of them).
From what I am seeing, those transformers are all under rated. A friends
house has 200A service and his transformer is only 8KVA.
pf...@aol.com
Feb 19, 2017, 4:48:57 PM2/19/17
to
What is coming into that transformer is typically 2,300V, and the rating is on the primary side. Meaning that if it is converting from 2,300V to 240V, for round figures and with losses thrown in, you are getting about 8 x the amps at the low end.
If watts is watts, again to be crude, 1 A @ 2,300 V = 10 A @ 230V v, each giving 2,300 watts. Now as there are two legs in the single-phase service, *EACH ONE* carries the nameplate rating. If that service is 3-phase, then you are getting even more.
Not to worry, those transformers are fused always on the primary, side, often on the secondary side. You may not see the secondary fuses, but you will see the primaries. No utility wants a fire on a pole, and certainly not at a remote location.
One more thing - we have a 200A service at our main house and at our summer house - the service was sized for electric heat, which we have never installed. At our main house, in the hottest part of the summer, we have never pulled even 150 A, (with 2 x 200 A available). That is with AC, a hot-tub, two refrigerators, freezer and a car charger. Our summer house - not even 60 A. No AC, but a hot tub, refrigerator, and car charger.
Does that help?
Peter Wieck
Melrose Park, PA
If watts is watts, again to be crude, 1 A @ 2,300 V = 10 A @ 230V v, each giving 2,300 watts. Now as there are two legs in the single-phase service, *EACH ONE* carries the nameplate rating. If that service is 3-phase, then you are getting even more.
Not to worry, those transformers are fused always on the primary, side, often on the secondary side. You may not see the secondary fuses, but you will see the primaries. No utility wants a fire on a pole, and certainly not at a remote location.
One more thing - we have a 200A service at our main house and at our summer house - the service was sized for electric heat, which we have never installed. At our main house, in the hottest part of the summer, we have never pulled even 150 A, (with 2 x 200 A available). That is with AC, a hot-tub, two refrigerators, freezer and a car charger. Our summer house - not even 60 A. No AC, but a hot tub, refrigerator, and car charger.
Does that help?
Peter Wieck
Melrose Park, PA
olds...@tubes.com
Feb 19, 2017, 5:55:35 PM2/19/17
to
On Sun, 19 Feb 2017 13:48:55 -0800 (PST), "pf...@aol.com" <pf...@aol.com>
wrote:
>If watts is watts, again to be crude, 1 A @ 2,300 V = 10 A @ 230V v,
[Quoting removed because of line lengths]
Yes, that makes sense. I was thinking the output was the amp rating.
Since you mentioned the fuses, I am aware of them on the input. In fact
years ago, I had one of them blow during a storm. A shower of sparks was
seen. The power company replaced it and all was fine again.
I do question how much they are fused to match the loads though. Some
years ago, I was at a yearly community meal at the small town's
reception center. I think every woman in town brought their electric
roasters, which use about 12 amps each. I counted 26 roasters, plus a
few large elec coffee pots. The building this was in, was fairly new,
with adaquate wiring. However, it was a very hot day. There is a trailer
park across the road, and I bet half them trailers had their air
conditioners on. That trailer park is to the same pole transformer. So,
add it up. 26 roasters = 312A. 3 coffee pots at around 10A each, plus
lighting, and that meal was drawing around 350A.
Who knows what the trailer park was drawing, and the meal center's AC
may have been on too.
Then the power went out. We had to eat cool food by candle light, until
the town's fire dept came with some generators for lighting.
The power company came, and they went up on the pole. The guy burned his
hand on that transformer. That thing was so hot they could not do
anything with it till it cooled. It was rated at 25 KVA. Hours later
they finally were able to replace it, and put in a 37.5 KVA. That
transformer fried before the fuse blew !
If that transformer had been touching the wooden post, I bet there would
have been a fire, but it was on brackets that held it away from the
wood. Even a few hours later, when they brought in a crane with a steel
cable to lower it to the ground, the guys said it was too hot to touch
and they could not load it on their truck. One of the guys suggested
hosing it with cold water, but I left before they did that.
wrote:
>If watts is watts, again to be crude, 1 A @ 2,300 V = 10 A @ 230V v,
Yes, that makes sense. I was thinking the output was the amp rating.
Since you mentioned the fuses, I am aware of them on the input. In fact
years ago, I had one of them blow during a storm. A shower of sparks was
seen. The power company replaced it and all was fine again.
I do question how much they are fused to match the loads though. Some
years ago, I was at a yearly community meal at the small town's
reception center. I think every woman in town brought their electric
roasters, which use about 12 amps each. I counted 26 roasters, plus a
few large elec coffee pots. The building this was in, was fairly new,
with adaquate wiring. However, it was a very hot day. There is a trailer
park across the road, and I bet half them trailers had their air
conditioners on. That trailer park is to the same pole transformer. So,
add it up. 26 roasters = 312A. 3 coffee pots at around 10A each, plus
lighting, and that meal was drawing around 350A.
Who knows what the trailer park was drawing, and the meal center's AC
may have been on too.
Then the power went out. We had to eat cool food by candle light, until
the town's fire dept came with some generators for lighting.
The power company came, and they went up on the pole. The guy burned his
hand on that transformer. That thing was so hot they could not do
anything with it till it cooled. It was rated at 25 KVA. Hours later
they finally were able to replace it, and put in a 37.5 KVA. That
transformer fried before the fuse blew !
If that transformer had been touching the wooden post, I bet there would
have been a fire, but it was on brackets that held it away from the
wood. Even a few hours later, when they brought in a crane with a steel
cable to lower it to the ground, the guys said it was too hot to touch
and they could not load it on their truck. One of the guys suggested
hosing it with cold water, but I left before they did that.
Rheilly Phoull
Feb 19, 2017, 7:52:20 PM2/19/17
to
pf...@aol.com
Feb 20, 2017, 6:59:37 AM2/20/17
to
On Sunday, February 19, 2017 at 7:52:20 PM UTC-5, Rheilly Phoull wrote:
>
> >
> AFAIK the fuses are to protect the tranny not the load.
Yep. The utility could care less about the load.
>
> >
> AFAIK the fuses are to protect the tranny not the load.
olds...@tubes.com
Feb 20, 2017, 7:46:53 AM2/20/17
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On Mon, 20 Feb 2017 03:59:35 -0800 (PST), "pf...@aol.com" <pf...@aol.com>
wrote:
The fuses did not protect the tranny in this case.....
wrote:
pf...@aol.com
Feb 20, 2017, 12:48:26 PM2/20/17
to
On Monday, February 20, 2017 at 7:46:53 AM UTC-5, olds...@tubes.com wrote:
> The fuses did not protect the tranny in this case.....
There is this about fuses.
> The fuses did not protect the tranny in this case.....
They are designed to handle the regular load + a certain level of brief heavy overloads, and then on a time/load lesser loads for a greater period.
There are rules of thumb, but consider that most fuses that could handle a 3x momentary surge can also handle a 10% overload pretty much indefinitely - at least as defined by the typical single-element fuse, even an oil-filled device.
At 2,300 V and 15KVA, that comes to 1.5A x 2,300 or about 3,500 watts... That transformer is gonna cook!! And that fuse is going to smile and suck it up.
Now, get me started on equipment fuses. I Will spare you the rant.
Phil Allison
Feb 20, 2017, 11:18:33 PM2/20/17
to
pf
>
> There are rules of thumb, but consider that most fuses that could
> handle a 3x momentary surge can also handle a 10% overload pretty
> much indefinitely - at least as defined by the typical single-element
> fuse, even an oil-filled device.
>
> At 2,300 V and 15KVA, that comes to 1.5A x 2,300 or about 3,500 watts...
> That transformer is gonna cook!!
>
** Makes not one tiny bit of sense.
But the Wieck troll rarely does.
.... Phil
>
> There are rules of thumb, but consider that most fuses that could
> handle a 3x momentary surge can also handle a 10% overload pretty
> much indefinitely - at least as defined by the typical single-element
> fuse, even an oil-filled device.
>
> At 2,300 V and 15KVA, that comes to 1.5A x 2,300 or about 3,500 watts...
> That transformer is gonna cook!!
>
But the Wieck troll rarely does.
.... Phil
pf...@aol.com
Feb 21, 2017, 8:03:16 AM2/21/17
to
On Monday, February 20, 2017 at 11:18:33 PM UTC-5, Phil Allison wrote:
>
Fair warning: I have come to the conclusion that Mr. Allison suffers from exposure to some sort of heavy metal - probably cadmium and lead - given his erratic behavior and the fact that it clearly does not respond to medication. And, if one wishes to understand the potential of these exposures, consider the case of Vincent Van Gogh.
Which would do nicely to explain the basic intelligence rendered toxic by toxins.
Very sad. And, irreversible.
>
Fair warning: I have come to the conclusion that Mr. Allison suffers from exposure to some sort of heavy metal - probably cadmium and lead - given his erratic behavior and the fact that it clearly does not respond to medication. And, if one wishes to understand the potential of these exposures, consider the case of Vincent Van Gogh.
Which would do nicely to explain the basic intelligence rendered toxic by toxins.
Very sad. And, irreversible.
avag...@gmail.com
Feb 21, 2017, 12:58:58 PM2/21/17
to
Bob F
Feb 21, 2017, 9:32:09 PM2/21/17
to
drawing. They might choose to replace the transformer. I was told onece
that if I increased usage significantly and did not tell them, I could
be responsible for the transformer being damaged. If I told them, no
problem.
Steve & Lynn
Feb 22, 2017, 9:27:13 PM2/22/17
to
> From what I am seeing, those transformers are all under rated. A friends
> house has 200A service and his transformer is only 8KVA.
>
WHAT SIZE TRANSFORMER DO YOU SUPPOSE SITRE MAGANA NEEDS IN ORDER TO PLAY
> house has 200A service and his transformer is only 8KVA.
>
WITH HIS OWN SHIT?
HOW MANY VOLT-AMPERES DOES ONE NEED TO FUCK A 72 YEAR OLD MAN AT A GAY ORGY?
HOW MANY AMP SERVICE DO YOU NEED TO CUT A HAMSTER TO PIECES WITH A PAIR
OF SCISSORS?
pf...@aol.com
Feb 23, 2017, 7:59:24 AM2/23/17
to
Little Timmee got hold of mommy's computer again.
If, of course, it even has a mommy.
If, of course, it even has a mommy.
Steve & Lynn
Feb 23, 2017, 3:21:52 PM2/23/17
to
On 02/23/2017 12:59 PM, pf...@aol.com wrote:
> Little Timmee got hold of mommy's computer again.
>
> If, of course, it even has a mommy.
>
THAT IS SO FUCKING GAY. THAT WAS SO GAY THAT IT EVEN MAKES SITRE MAGANA
> Little Timmee got hold of mommy's computer again.
>
> If, of course, it even has a mommy.
>
LOOKS STRAIGHT. IF YOU POST SOMETHING AND IT WAS SO GAY THAT IT MAKES
SITRE MAGANA A MAN WHO SERVICED A 72 YEAR OLD MAN AT A GAY ORGAY LOOK
STRAIGHT, THEN YOU KNOW IT MUST BE LIKE THE GAYEST THING IN THE WORLD.
Steve & Lynn
Feb 23, 2017, 3:28:54 PM2/23/17
to
On 02/19/2017 09:48 PM, pf...@aol.com wrote:
> Our summer house - not even 60 A. No AC, but a hot tub, refrigerator, and car charger.
>
BUT THEN ALL YOU DO AT YOUR SUMMER HOUSE IS HAVE GAY ORGIES. LIKE HAVE A
> Our summer house - not even 60 A. No AC, but a hot tub, refrigerator, and car charger.
>
THREESOME IN YOUR HOT TUB WITH SITRE MAGANA AND HIS 72 YEAR OLD BOYFRIEND.
David Lesher
Mar 11, 2017, 9:57:36 PM3/11/17
to
"pf...@aol.com" <pf...@aol.com> writes:
>On Monday, February 20, 2017 at 7:46:53 AM UTC-5, olds...@tubes.com wrote:
>> The fuses did not protect the tranny in this case.....
>There is this about fuses.
>They are designed to handle the regular load + a certain level
>of brief heavy overloads, and then on a time/load lesser loads
>for a greater period.
The pole pigs around here have 2 fuses. Mine has a 10A and a 15A
>On Monday, February 20, 2017 at 7:46:53 AM UTC-5, olds...@tubes.com wrote:
>> The fuses did not protect the tranny in this case.....
>There is this about fuses.
>They are designed to handle the regular load + a certain level
>of brief heavy overloads, and then on a time/load lesser loads
>for a greater period.
in series. I asked why two. Turns out the 10A is the rated one
and cheap; the 15A is fast, $$$, and solely protects against
lightning hits on the primary.
But I know the "rated" load of such a transformer is continuous,
and they are routinely overloaded for a few hours.
--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close..........................
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433
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