Forums

Harmonics in pole power transformers?

Started by Joerg April 17, 2016
Joerg wrote:
> > On 2016-04-18 17:17, whit3rd wrote: > > On Monday, April 18, 2016 at 4:38:12 PM UTC-7, Joerg wrote: > > > >> The goal is to have a single self-contained "sniffer box", no wires, > >> nothing going in and out in terms of connections. > > > > If nothing goes out, you never get any information, of course... > > which simplifies the 'sniffer' function, you just drop that requirement. > > > > If you can't standardize on a meter that has reporting, or wire a > > reporting relay inside a breaker box, or depend on a noisy or light-emitting > > or signal-flag-waving bit of driven apparatus, the power from that > > pole pig transformer is only a potential, not an action with consequences. > > I'm dubious that the potential alone, within "a metal enclosure", is > > something that can be reliably sensed from without. > > > > Yes, like "Mixed Nuts" (Or Grizzly H.?) wrote the E-field will be very > paltry. But we'll have to try.
How will that detect a damaged pipe? Or a pump with a bad shear pin? --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
On Tue, 19 Apr 2016 07:25:48 -0700, Joerg <news@analogconsultants.com>
wrote:

>On 2016-04-18 17:44, John Larkin wrote: >> On Mon, 18 Apr 2016 16:31:39 -0700, Joerg <news@analogconsultants.com> >> wrote: >> >>> On 2016-04-18 14:50, whit3rd wrote: >>>> On Monday, April 18, 2016 at 8:02:21 AM UTC-7, Joerg wrote: >>>>> On 2016-04-18 07:48, Phil Hobbs wrote: >>>> >>>>>> I'd be wanting to move the goal posts and cycle the pump every few hours >>>>>> just to make sure. >>>> >>>>> We can't. It's all automatic and often legacy equipment that some might >>>>> even call pre-historic. >>>> >>>> Just for giggles: is there a meter on these drops? A smart meter, that takes >>>> 3W all the time, that has wireless reporting back to the utility? If you >>>> could read out the meter, it'd solve the problem instantly. >>>> >>> >>> Can't rely on that, we have to cover all situations. Many places will >>> still have analog meters, some may not have meters at all and instead >>> pay a flat rate. Or they are on a company/farm grid where there is no >>> need for metering. >> >> Well, don't make it too easy on us. >> > >I love those kinds of jobs where you have next to nothing to use as >input and you have to make it work anyhow.
But some fraction of those things are impossible. So, how much does a coundit vibrate from the electrostatic or piezo forces on the wires? -- John Larkin Highland Technology, Inc lunatic fringe electronics
On 04/19/2016 06:07 AM, Jasen Betts wrote:
> On 2016-04-18, Joerg <news@analogconsultants.com> wrote: >> On 2016-04-18 09:41, Adrian Tuddenham wrote: >>> Joerg <news@analogconsultants.com> wrote: > >> That would require an electrician to come out and most would refuse this >> job because they, their employer or their union won't allow non-standard >> stuff. > > Yeah, and if they're paying a visit they could as easily install a > standard electical outlet for you to plug your alarm into. > >
One gathers that the customer is building the gizmos, not running the cattle. Remember, fishing lures are designed to catch fishermen. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Joerg <news@analogconsultants.com> wrote:
> On 2016-04-18 15:02, Lasse Langwadt Christensen wrote: >> Den mandag den 18. april 2016 kl. 23.50.56 UTC+2 skrev legg: >>> On Mon, 18 Apr 2016 07:58:30 -0700, Joerg <news@analogconsultants.com> >>> wrote: >>> >>>> On 2016-04-18 07:57, legg wrote: >>>>> On Sun, 17 Apr 2016 17:16:12 -0700 (PDT), George Herold >>>>> <gherold@teachspin.com> wrote: >>>>> >>>>>> On Sunday, April 17, 2016 at 4:54:36 PM UTC-4, Joerg wrote: >>>>>>> Folks, >>>>>>> >>>>>>> A system needs to be able to detect whether a pole transformer has >>>>>>> failed and stopped feeding power to a pump. The transformer will be >>>>>>> 100ft or more away. The detection has to work even without any power >>>>>>> flow meaning we can only detect the presence of a 60Hz electric field >>>>>>> that leaks from the various boxs such as a breaker box. >>>>>>> >>>>>>> In order not to get fooled by 60Hz from other overhead lines I was >>>>>>> wondering if classic pole transformers generate enough 3rd and 5th >>>>>>> harmonics to distinguish the field emanating from secondary wires from >>>>>>> that coming from overhead HV lines. Does anyone know where to find info >>>>>>> about that? >>>>>>> >>>>>>> -- >>>>>>> Regards, Joerg >>>>>>> >>>>>>> http://www.analogconsultants.com/ >>>>>> >>>>>> Magneto-striction causes the transformer to vibrate at 120 Hz, >>>>>> I don't know if you could sense that. >>>>>> >>>> >>>> Audio buzz isn't reliable here because the transformer will be far away. >>>> All we have is any E-field leaking out from conduit and the breaker box. >>>> The good thing is, we can be right at the breaker box, just not in it. >>>> >>>> >>>>>> George H. >>>>> >>>>> Transformers can fail and still buzz. >>>>> >>>>> There are many reasons why a pump might fail. Expending effort at >>>>> sensing just a single one of these is misdirected. >>>>> >>>> >>>> No, it is not. The fact that transformer or HV line failure is by far >>>> the highest concern in this application is based on clear statistical >>>> evidence. >>>> >>> I'd like to see THOSE statistics. >>> >>> You're trying to see if a pump is functional, when it's not supposed >>> to be running. Does this make sense to you? >> >> if it is, say, a pump to keep a basement from flooding or some cows from >> going thirsty it makes perfect sense to get an electrician out to fix the >> power before it is needed >> > > Bingo!
No. It costs too much to hire electricians. The problem will have to fix itself.
Jasen Betts <jasen@xnet.co.nz> wrote:
> On 2016-04-18, Joerg <news@analogconsultants.com> wrote: >> On 2016-04-18 09:41, Adrian Tuddenham wrote: >>> Joerg <news@analogconsultants.com> wrote: > >> That would require an electrician to come out and most would refuse this >> job because they, their employer or their union won't allow non-standard >> stuff. > > Yeah, and if they're paying a visit they could as easily install a > standard electical outlet for you to plug your alarm into.
Ha!
On 04/19/2016 12:19 PM, Cydrome Leader wrote:
> Joerg <news@analogconsultants.com> wrote: >> On 2016-04-18 15:02, Lasse Langwadt Christensen wrote: >>> Den mandag den 18. april 2016 kl. 23.50.56 UTC+2 skrev legg: >>>> On Mon, 18 Apr 2016 07:58:30 -0700, Joerg <news@analogconsultants.com> >>>> wrote: >>>> >>>>> On 2016-04-18 07:57, legg wrote: >>>>>> On Sun, 17 Apr 2016 17:16:12 -0700 (PDT), George Herold >>>>>> <gherold@teachspin.com> wrote: >>>>>> >>>>>>> On Sunday, April 17, 2016 at 4:54:36 PM UTC-4, Joerg wrote: >>>>>>>> Folks, >>>>>>>> >>>>>>>> A system needs to be able to detect whether a pole transformer has >>>>>>>> failed and stopped feeding power to a pump. The transformer will be >>>>>>>> 100ft or more away. The detection has to work even without any power >>>>>>>> flow meaning we can only detect the presence of a 60Hz electric field >>>>>>>> that leaks from the various boxs such as a breaker box. >>>>>>>> >>>>>>>> In order not to get fooled by 60Hz from other overhead lines I was >>>>>>>> wondering if classic pole transformers generate enough 3rd and 5th >>>>>>>> harmonics to distinguish the field emanating from secondary wires from >>>>>>>> that coming from overhead HV lines. Does anyone know where to find info >>>>>>>> about that? >>>>>>>> >>>>>>>> -- >>>>>>>> Regards, Joerg >>>>>>>> >>>>>>>> http://www.analogconsultants.com/ >>>>>>> >>>>>>> Magneto-striction causes the transformer to vibrate at 120 Hz, >>>>>>> I don't know if you could sense that. >>>>>>> >>>>> >>>>> Audio buzz isn't reliable here because the transformer will be far away. >>>>> All we have is any E-field leaking out from conduit and the breaker box. >>>>> The good thing is, we can be right at the breaker box, just not in it. >>>>> >>>>> >>>>>>> George H. >>>>>> >>>>>> Transformers can fail and still buzz. >>>>>> >>>>>> There are many reasons why a pump might fail. Expending effort at >>>>>> sensing just a single one of these is misdirected. >>>>>> >>>>> >>>>> No, it is not. The fact that transformer or HV line failure is by far >>>>> the highest concern in this application is based on clear statistical >>>>> evidence. >>>>> >>>> I'd like to see THOSE statistics. >>>> >>>> You're trying to see if a pump is functional, when it's not supposed >>>> to be running. Does this make sense to you? >>> >>> if it is, say, a pump to keep a basement from flooding or some cows from >>> going thirsty it makes perfect sense to get an electrician out to fix the >>> power before it is needed >>> >> >> Bingo! > > No. It costs too much to hire electricians. The problem will have to fix > itself. > >
If you're the farmer or building owner, it's reasonable. On the other hand, if you're selling gizmos that will on average save several hundred dollars' worth of wasted time every few years, you can charge more for your gizmo. Everybody wins. What's not to like? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
On 2016-04-19 08:12, John Larkin wrote:
> On Tue, 19 Apr 2016 07:25:48 -0700, Joerg <news@analogconsultants.com> > wrote: > >> On 2016-04-18 17:44, John Larkin wrote: >>> On Mon, 18 Apr 2016 16:31:39 -0700, Joerg <news@analogconsultants.com> >>> wrote: >>> >>>> On 2016-04-18 14:50, whit3rd wrote: >>>>> On Monday, April 18, 2016 at 8:02:21 AM UTC-7, Joerg wrote: >>>>>> On 2016-04-18 07:48, Phil Hobbs wrote: >>>>> >>>>>>> I'd be wanting to move the goal posts and cycle the pump every few hours >>>>>>> just to make sure. >>>>> >>>>>> We can't. It's all automatic and often legacy equipment that some might >>>>>> even call pre-historic. >>>>> >>>>> Just for giggles: is there a meter on these drops? A smart meter, that takes >>>>> 3W all the time, that has wireless reporting back to the utility? If you >>>>> could read out the meter, it'd solve the problem instantly. >>>>> >>>> >>>> Can't rely on that, we have to cover all situations. Many places will >>>> still have analog meters, some may not have meters at all and instead >>>> pay a flat rate. Or they are on a company/farm grid where there is no >>>> need for metering. >>> >>> Well, don't make it too easy on us. >>> >> >> I love those kinds of jobs where you have next to nothing to use as >> input and you have to make it work anyhow. > > But some fraction of those things are impossible. > > So, how much does a coundit vibrate from the electrostatic or piezo > forces on the wires? >
No idea. We'll first try the 60Hz field sniffer. It might be a dud but we won't know without trying. -- Regards, Joerg http://www.analogconsultants.com/
On 2016-04-19 08:04, Michael A. Terrell wrote:
> > Joerg wrote: >> >> On 2016-04-18 17:17, whit3rd wrote: >>> On Monday, April 18, 2016 at 4:38:12 PM UTC-7, Joerg wrote: >>> >>>> The goal is to have a single self-contained "sniffer box", no wires, >>>> nothing going in and out in terms of connections. >>> >>> If nothing goes out, you never get any information, of course... >>> which simplifies the 'sniffer' function, you just drop that requirement. >>> >>> If you can't standardize on a meter that has reporting, or wire a >>> reporting relay inside a breaker box, or depend on a noisy or light-emitting >>> or signal-flag-waving bit of driven apparatus, the power from that >>> pole pig transformer is only a potential, not an action with consequences. >>> I'm dubious that the potential alone, within "a metal enclosure", is >>> something that can be reliably sensed from without. >>> >> >> Yes, like "Mixed Nuts" (Or Grizzly H.?) wrote the E-field will be very >> paltry. But we'll have to try. > > > How will that detect a damaged pipe? Or a pump with a bad shear pin? >
That's already being detected. But we must differentiate between a pipe failure or whatever and a mains power failure. Because if they send the wrong crew out it's going to cost them an unnecessary few hundred Dollars every time. Like when the phone company service truck comes out and then they determine the fault was on your premises. Then they typically send you a bill. If it was before the demarc they don't but if you had called a private phone services and the utility side is down then they send you a bill without having fixed anything. Such scenarios to be avoided here. -- Regards, Joerg http://www.analogconsultants.com/
Joerg wrote:

> On 2016-04-17 16:39, Jon Elson wrote: >> Joerg wrote: >> >> >>> In order not to get fooled by 60Hz from other overhead lines I was >>> wondering if classic pole transformers generate enough 3rd and 5th >>> harmonics to distinguish the field emanating from secondary wires from >>> that coming from overhead HV lines. Does anyone know where to find info >>> about that? >>> >> Geez, I would expect there to be VERY little 3rd or 5th harmonic from a >> transformer. These harmonics require a nonlinear response, and they >> shouldn't be nonlinear. >> > > All transformers are non-linear because there is an economical limit to > the amount of copper they put on there. My question is just, how > non-linear is the average pole transformer? >
I'd guess, VERY linear. The non-linearity is due to saturation of the core. Since the power company pays for all losses before the electric meter, I'd guess they are happy to pay for a little more copper and iron, so they don't have to pay for those losses over the next 50 years. Jon
Joerg wrote:


> No, it is not. The fact that transformer or HV line failure is by far > the highest concern in this application is based on clear statistical > evidence.
Why not put capacitive plates next to the power feed (likely a Romex-style cable) near the breakers. You can probably get a really good signal if you wrapped two pieces of aluminum foil around the cable for 6" or so. Then, you could connect these to a low-impedance amplifier, and test the signal for the right frequency and voltage. It should have no trouble detecting the difference between good mains power and some small induction when the mains power fails. Jon