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Trust your what-hour err watt hour meter

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  Trust your what-hour err watt hour meter David Lesher <wb8foz@panix.com> - 2017-03-06 17:25 +0000
    Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 10:29 -0800
      Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-06 14:10 -0500
        Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 14:21 -0800
          Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-06 18:20 -0500
            Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 16:35 -0800
              Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-06 19:53 -0500
                Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 17:08 -0800
                  Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-07 13:05 -0500
                    Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-07 10:43 -0800
                      Re: Trust your what-hour err watt hour meter Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-03-07 14:21 -0500
        Re: Trust your what-hour err watt hour meter whit3rd <whit3rd@gmail.com> - 2017-03-06 18:36 -0800
    Re: Trust your what-hour err watt hour meter rickman <gnuarm@gmail.com> - 2017-03-06 14:52 -0500
      Re: Trust your what-hour err watt hour meter George Herold <gherold@teachspin.com> - 2017-03-06 12:04 -0800
        Re: Trust your what-hour err watt hour meter rickman <gnuarm@gmail.com> - 2017-03-06 15:15 -0500
        Re: Trust your what-hour err watt hour meter Jon Elson <jmelson@wustl.edu> - 2017-03-06 14:28 -0600
          Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 16:41 -0800
      Re: Trust your what-hour err watt hour meter Jon Elson <jmelson@wustl.edu> - 2017-03-06 14:26 -0600
        Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-06 15:30 -0500
      Re: Trust your what-hour err watt hour meter bitrex <bitrex@de.lete.earthlink.net> - 2017-03-06 15:28 -0500
        Re: Trust your what-hour err watt hour meter rickman <gnuarm@gmail.com> - 2017-03-06 16:04 -0500
        Re: Trust your what-hour err watt hour meter Jeff Liebermann <jeffl@cruzio.com> - 2017-03-06 16:22 -0800
          Re: Trust your what-hour err watt hour meter David Lesher <wb8foz@panix.com> - 2017-03-09 16:03 +0000
            Re: Trust your what-hour err watt hour meter Wim Ton <wim.ton@gmail.com> - 2017-03-09 12:39 -0800
            Re: Trust your what-hour err watt hour meter Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-03-09 15:46 -0800
    Re: Trust your what-hour err watt hour meter TTman <pcw1.cad@ntlworld.com> - 2017-03-06 21:48 +0000
      Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-06 14:32 -0800
        Re: Trust your what-hour err watt hour meter David Lesher <wb8foz@panix.com> - 2017-03-09 16:30 +0000
          Re: Trust your what-hour err watt hour meter makolber@yahoo.com - 2017-03-09 12:27 -0800
            Re: Trust your what-hour err watt hour meter Neon John <no@never.com> - 2017-03-09 15:43 -0500
              Re: Trust your what-hour err watt hour meter Wim Ton <wim.ton@gmail.com> - 2017-03-09 12:49 -0800
                Re: Trust your what-hour err watt hour meter Neon John <no@never.com> - 2017-03-11 11:11 -0500
                  Re: Trust your what-hour err watt hour meter Wim Ton <wim.ton@gmail.com> - 2017-03-11 12:28 -0800
              Re: Trust your what-hour err watt hour meter John Larkin <jjlarkinxyxy@highlandtechnology.com> - 2017-03-09 12:59 -0800
                Re: Trust your what-hour err watt hour meter Neon John <no@never.com> - 2017-03-11 17:38 -0500
                  Re: Trust your what-hour err watt hour meter John Larkin <jjlarkin@highlandtechnology.com> - 2017-03-11 15:04 -0800
          Re: Trust your what-hour err watt hour meter Wim Ton <wim.ton@gmail.com> - 2017-03-09 12:47 -0800
      Re: Trust your what-hour err watt hour meter Neon John <no@never.com> - 2017-03-08 20:05 -0500
        Re: Trust your what-hour err watt hour meter Phil Allison <pallison49@gmail.com> - 2017-03-11 17:42 -0800
    Re: Trust your what-hour err watt hour meter Phil Allison <pallison49@gmail.com> - 2017-03-06 17:53 -0800
    Re: Trust your what-hour err watt hour meter Cursitor Doom <curd@notformail.com> - 2017-03-07 17:58 +0000
    Re: Trust your what-hour err watt hour meter Anthony Stewart <tony.sunnysky@gmail.com> - 2017-03-09 15:31 -0800

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#450466 — Trust your what-hour err watt hour meter

<https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>

....."The inaccurate readings are attributed to the energy meter's
design, together with the increasing use of modern (often
energy-efficient) switching devices. Here, the electricity being
consumed no longer has a perfect waveform, instead it acquires
an erratic pattern. The designers of modern energy meters
have not made sufficient allowance for switching devices of
this kind. When they dismantled the energy meters tested, the
researchers found that the ones associated with excessively high
readings contained a 'Rogowski Coil' while those associated with
excessively low readings contained a 'Hall Sensor'."

I smell lawsuits since the PoCo's have been removing the
old meters en mass....
-- 
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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#450477

On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
<wb8foz@panix.com> wrote:

><https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>
>....."The inaccurate readings are attributed to the energy meter's
>design, together with the increasing use of modern (often
>energy-efficient) switching devices. Here, the electricity being
>consumed no longer has a perfect waveform, instead it acquires
>an erratic pattern. The designers of modern energy meters
>have not made sufficient allowance for switching devices of
>this kind. When they dismantled the energy meters tested, the
>researchers found that the ones associated with excessively high
>readings contained a 'Rogowski Coil' while those associated with
>excessively low readings contained a 'Hall Sensor'."

Neither is really associated with measurement error. The downstream
signal processing is.

>
>I smell lawsuits since the PoCo's have been removing the
>old meters en mass....

It's not hard to make a meter that measures and integrates true power
correctly. You can even buy chips that do all the hard work for you.

I suppose there can be a DC component of the power (like a
diode+resistor load) that an AC-coupled meter (regular CT, Rogowski)
would miss. So a real current-shunt sensor or DC-coupled Hall is more
accurate.


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450485

On 03/06/2017 01:29 PM, John Larkin wrote:
> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
> <wb8foz@panix.com> wrote:
>
>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>
>> ....."The inaccurate readings are attributed to the energy meter's
>> design, together with the increasing use of modern (often
>> energy-efficient) switching devices. Here, the electricity being
>> consumed no longer has a perfect waveform, instead it acquires
>> an erratic pattern. The designers of modern energy meters
>> have not made sufficient allowance for switching devices of
>> this kind. When they dismantled the energy meters tested, the
>> researchers found that the ones associated with excessively high
>> readings contained a 'Rogowski Coil' while those associated with
>> excessively low readings contained a 'Hall Sensor'."
>
> Neither is really associated with measurement error. The downstream
> signal processing is.
>
>>
>> I smell lawsuits since the PoCo's have been removing the
>> old meters en mass....
>
> It's not hard to make a meter that measures and integrates true power
> correctly. You can even buy chips that do all the hard work for you.

555 timer.

The "Design an accurate true power meter with a 555" challenge!

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#450518

On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/06/2017 01:29 PM, John Larkin wrote:
>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>> <wb8foz@panix.com> wrote:
>>
>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>
>>> ....."The inaccurate readings are attributed to the energy meter's
>>> design, together with the increasing use of modern (often
>>> energy-efficient) switching devices. Here, the electricity being
>>> consumed no longer has a perfect waveform, instead it acquires
>>> an erratic pattern. The designers of modern energy meters
>>> have not made sufficient allowance for switching devices of
>>> this kind. When they dismantled the energy meters tested, the
>>> researchers found that the ones associated with excessively high
>>> readings contained a 'Rogowski Coil' while those associated with
>>> excessively low readings contained a 'Hall Sensor'."
>>
>> Neither is really associated with measurement error. The downstream
>> signal processing is.
>>
>>>
>>> I smell lawsuits since the PoCo's have been removing the
>>> old meters en mass....
>>
>> It's not hard to make a meter that measures and integrates true power
>> correctly. You can even buy chips that do all the hard work for you.
>
>555 timer.
>
>The "Design an accurate true power meter with a 555" challenge!
>

Can I use a few opamps too?

A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
were popular for precision multiplies and divides and square roots
once.


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450520

On 03/06/2017 05:21 PM, John Larkin wrote:
> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
> <bitrex@de.lete.earthlink.net> wrote:
>
>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>> <wb8foz@panix.com> wrote:
>>>
>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>
>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>> design, together with the increasing use of modern (often
>>>> energy-efficient) switching devices. Here, the electricity being
>>>> consumed no longer has a perfect waveform, instead it acquires
>>>> an erratic pattern. The designers of modern energy meters
>>>> have not made sufficient allowance for switching devices of
>>>> this kind. When they dismantled the energy meters tested, the
>>>> researchers found that the ones associated with excessively high
>>>> readings contained a 'Rogowski Coil' while those associated with
>>>> excessively low readings contained a 'Hall Sensor'."
>>>
>>> Neither is really associated with measurement error. The downstream
>>> signal processing is.
>>>
>>>>
>>>> I smell lawsuits since the PoCo's have been removing the
>>>> old meters en mass....
>>>
>>> It's not hard to make a meter that measures and integrates true power
>>> correctly. You can even buy chips that do all the hard work for you.
>>
>> 555 timer.
>>
>> The "Design an accurate true power meter with a 555" challenge!
>>
>
> Can I use a few opamps too?
>
> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
> were popular for precision multiplies and divides and square roots
> once.
>
>

The LM324 or the '741, your choice! ;-)

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#450538

On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/06/2017 05:21 PM, John Larkin wrote:
>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>> <bitrex@de.lete.earthlink.net> wrote:
>>
>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>> <wb8foz@panix.com> wrote:
>>>>
>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>
>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>> design, together with the increasing use of modern (often
>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>> an erratic pattern. The designers of modern energy meters
>>>>> have not made sufficient allowance for switching devices of
>>>>> this kind. When they dismantled the energy meters tested, the
>>>>> researchers found that the ones associated with excessively high
>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>
>>>> Neither is really associated with measurement error. The downstream
>>>> signal processing is.
>>>>
>>>>>
>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>> old meters en mass....
>>>>
>>>> It's not hard to make a meter that measures and integrates true power
>>>> correctly. You can even buy chips that do all the hard work for you.
>>>
>>> 555 timer.
>>>
>>> The "Design an accurate true power meter with a 555" challenge!
>>>
>>
>> Can I use a few opamps too?
>>
>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>> were popular for precision multiplies and divides and square roots
>> once.
>>
>>
>
>The LM324 or the '741, your choice! ;-)

uA709?


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450541

On 03/06/2017 07:35 PM, John Larkin wrote:
> On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
> <bitrex@de.lete.earthlink.net> wrote:
>
>> On 03/06/2017 05:21 PM, John Larkin wrote:
>>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>>> <bitrex@de.lete.earthlink.net> wrote:
>>>
>>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>>> <wb8foz@panix.com> wrote:
>>>>>
>>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>>
>>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>>> design, together with the increasing use of modern (often
>>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>>> an erratic pattern. The designers of modern energy meters
>>>>>> have not made sufficient allowance for switching devices of
>>>>>> this kind. When they dismantled the energy meters tested, the
>>>>>> researchers found that the ones associated with excessively high
>>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>>
>>>>> Neither is really associated with measurement error. The downstream
>>>>> signal processing is.
>>>>>
>>>>>>
>>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>>> old meters en mass....
>>>>>
>>>>> It's not hard to make a meter that measures and integrates true power
>>>>> correctly. You can even buy chips that do all the hard work for you.
>>>>
>>>> 555 timer.
>>>>
>>>> The "Design an accurate true power meter with a 555" challenge!
>>>>
>>>
>>> Can I use a few opamps too?
>>>
>>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>>> were popular for precision multiplies and divides and square roots
>>> once.
>>>
>>>
>>
>> The LM324 or the '741, your choice! ;-)
>
> uA709?
>
>

Probably allowed, IIRC it's older but better spec-ed than either, just 
not internally compensated and not unity-gain stable without a bunch of 
external parts...

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#450544

On Mon, 6 Mar 2017 19:53:44 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/06/2017 07:35 PM, John Larkin wrote:
>> On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
>> <bitrex@de.lete.earthlink.net> wrote:
>>
>>> On 03/06/2017 05:21 PM, John Larkin wrote:
>>>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>
>>>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>>>> <wb8foz@panix.com> wrote:
>>>>>>
>>>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>>>
>>>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>>>> design, together with the increasing use of modern (often
>>>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>>>> an erratic pattern. The designers of modern energy meters
>>>>>>> have not made sufficient allowance for switching devices of
>>>>>>> this kind. When they dismantled the energy meters tested, the
>>>>>>> researchers found that the ones associated with excessively high
>>>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>>>
>>>>>> Neither is really associated with measurement error. The downstream
>>>>>> signal processing is.
>>>>>>
>>>>>>>
>>>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>>>> old meters en mass....
>>>>>>
>>>>>> It's not hard to make a meter that measures and integrates true power
>>>>>> correctly. You can even buy chips that do all the hard work for you.
>>>>>
>>>>> 555 timer.
>>>>>
>>>>> The "Design an accurate true power meter with a 555" challenge!
>>>>>
>>>>
>>>> Can I use a few opamps too?
>>>>
>>>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>>>> were popular for precision multiplies and divides and square roots
>>>> once.
>>>>
>>>>
>>>
>>> The LM324 or the '741, your choice! ;-)
>>
>> uA709?
>>
>>
>
>Probably allowed, IIRC it's older but better spec-ed than either, just 
>not internally compensated and not unity-gain stable without a bunch of 
>external parts...

It made a decent comparator, uncompensated. But the NPN diff pair
would zener, and it liked to latch up. 


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450647

On 03/06/2017 08:08 PM, John Larkin wrote:
> On Mon, 6 Mar 2017 19:53:44 -0500, bitrex
> <bitrex@de.lete.earthlink.net> wrote:
>
>> On 03/06/2017 07:35 PM, John Larkin wrote:
>>> On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
>>> <bitrex@de.lete.earthlink.net> wrote:
>>>
>>>> On 03/06/2017 05:21 PM, John Larkin wrote:
>>>>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>>
>>>>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>>>>> <wb8foz@panix.com> wrote:
>>>>>>>
>>>>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>>>>
>>>>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>>>>> design, together with the increasing use of modern (often
>>>>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>>>>> an erratic pattern. The designers of modern energy meters
>>>>>>>> have not made sufficient allowance for switching devices of
>>>>>>>> this kind. When they dismantled the energy meters tested, the
>>>>>>>> researchers found that the ones associated with excessively high
>>>>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>>>>
>>>>>>> Neither is really associated with measurement error. The downstream
>>>>>>> signal processing is.
>>>>>>>
>>>>>>>>
>>>>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>>>>> old meters en mass....
>>>>>>>
>>>>>>> It's not hard to make a meter that measures and integrates true power
>>>>>>> correctly. You can even buy chips that do all the hard work for you.
>>>>>>
>>>>>> 555 timer.
>>>>>>
>>>>>> The "Design an accurate true power meter with a 555" challenge!
>>>>>>
>>>>>
>>>>> Can I use a few opamps too?
>>>>>
>>>>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>>>>> were popular for precision multiplies and divides and square roots
>>>>> once.
>>>>>
>>>>>
>>>>
>>>> The LM324 or the '741, your choice! ;-)
>>>
>>> uA709?
>>>
>>>
>>
>> Probably allowed, IIRC it's older but better spec-ed than either, just
>> not internally compensated and not unity-gain stable without a bunch of
>> external parts...
>
> It made a decent comparator, uncompensated. But the NPN diff pair
> would zener, and it liked to latch up.
>

The input stage isn't like anything I've seen before (i.e. modern) - two 
Darlington followers on either side of load resistors in the collectors 
of the LTP, fed by a constant voltage source.

IIRC all op-amps that have resistive loads tied to the positive supply 
instead of current-mirror loads are prone to latch-up, for a technical 
reason that escapes me at the moment.

Why they do it like that? Something about monolithic small-signal PNPs 
with good enough specs not being possible to lay down with the 
fabrication process available in '67 or something?

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#450655

On Tue, 7 Mar 2017 13:05:44 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/06/2017 08:08 PM, John Larkin wrote:
>> On Mon, 6 Mar 2017 19:53:44 -0500, bitrex
>> <bitrex@de.lete.earthlink.net> wrote:
>>
>>> On 03/06/2017 07:35 PM, John Larkin wrote:
>>>> On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>
>>>>> On 03/06/2017 05:21 PM, John Larkin wrote:
>>>>>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>>>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>>>
>>>>>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>>>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>>>>>> <wb8foz@panix.com> wrote:
>>>>>>>>
>>>>>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>>>>>
>>>>>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>>>>>> design, together with the increasing use of modern (often
>>>>>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>>>>>> an erratic pattern. The designers of modern energy meters
>>>>>>>>> have not made sufficient allowance for switching devices of
>>>>>>>>> this kind. When they dismantled the energy meters tested, the
>>>>>>>>> researchers found that the ones associated with excessively high
>>>>>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>>>>>
>>>>>>>> Neither is really associated with measurement error. The downstream
>>>>>>>> signal processing is.
>>>>>>>>
>>>>>>>>>
>>>>>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>>>>>> old meters en mass....
>>>>>>>>
>>>>>>>> It's not hard to make a meter that measures and integrates true power
>>>>>>>> correctly. You can even buy chips that do all the hard work for you.
>>>>>>>
>>>>>>> 555 timer.
>>>>>>>
>>>>>>> The "Design an accurate true power meter with a 555" challenge!
>>>>>>>
>>>>>>
>>>>>> Can I use a few opamps too?
>>>>>>
>>>>>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>>>>>> were popular for precision multiplies and divides and square roots
>>>>>> once.
>>>>>>
>>>>>>
>>>>>
>>>>> The LM324 or the '741, your choice! ;-)
>>>>
>>>> uA709?
>>>>
>>>>
>>>
>>> Probably allowed, IIRC it's older but better spec-ed than either, just
>>> not internally compensated and not unity-gain stable without a bunch of
>>> external parts...
>>
>> It made a decent comparator, uncompensated. But the NPN diff pair
>> would zener, and it liked to latch up.
>>
>
>The input stage isn't like anything I've seen before (i.e. modern) - two 
>Darlington followers on either side of load resistors in the collectors 
>of the LTP, fed by a constant voltage source.
>
>IIRC all op-amps that have resistive loads tied to the positive supply 
>instead of current-mirror loads are prone to latch-up, for a technical 
>reason that escapes me at the moment.
>
>Why they do it like that? Something about monolithic small-signal PNPs 
>with good enough specs not being possible to lay down with the 
>fabrication process available in '67 or something?

There's one PNP in the 709. Probably not a very good one. The slew
rate is glacial, 0.25 volts per us.

There were some all-NPN opamps back then that were really awful.

At some point I decided to start using 741s, which was a
million-dollar decision at the time. But prices dropped fast.


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450669

On 03/07/2017 01:43 PM, John Larkin wrote:
> On Tue, 7 Mar 2017 13:05:44 -0500, bitrex
> <bitrex@de.lete.earthlink.net> wrote:
> 
>> On 03/06/2017 08:08 PM, John Larkin wrote:
>>> On Mon, 6 Mar 2017 19:53:44 -0500, bitrex
>>> <bitrex@de.lete.earthlink.net> wrote:
>>>
>>>> On 03/06/2017 07:35 PM, John Larkin wrote:
>>>>> On Mon, 6 Mar 2017 18:20:38 -0500, bitrex
>>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>>
>>>>>> On 03/06/2017 05:21 PM, John Larkin wrote:
>>>>>>> On Mon, 6 Mar 2017 14:10:19 -0500, bitrex
>>>>>>> <bitrex@de.lete.earthlink.net> wrote:
>>>>>>>
>>>>>>>> On 03/06/2017 01:29 PM, John Larkin wrote:
>>>>>>>>> On Mon, 6 Mar 2017 17:25:05 +0000 (UTC), David Lesher
>>>>>>>>> <wb8foz@panix.com> wrote:
>>>>>>>>>
>>>>>>>>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>>>>>>>>
>>>>>>>>>> ....."The inaccurate readings are attributed to the energy meter's
>>>>>>>>>> design, together with the increasing use of modern (often
>>>>>>>>>> energy-efficient) switching devices. Here, the electricity being
>>>>>>>>>> consumed no longer has a perfect waveform, instead it acquires
>>>>>>>>>> an erratic pattern. The designers of modern energy meters
>>>>>>>>>> have not made sufficient allowance for switching devices of
>>>>>>>>>> this kind. When they dismantled the energy meters tested, the
>>>>>>>>>> researchers found that the ones associated with excessively high
>>>>>>>>>> readings contained a 'Rogowski Coil' while those associated with
>>>>>>>>>> excessively low readings contained a 'Hall Sensor'."
>>>>>>>>>
>>>>>>>>> Neither is really associated with measurement error. The downstream
>>>>>>>>> signal processing is.
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> I smell lawsuits since the PoCo's have been removing the
>>>>>>>>>> old meters en mass....
>>>>>>>>>
>>>>>>>>> It's not hard to make a meter that measures and integrates true power
>>>>>>>>> correctly. You can even buy chips that do all the hard work for you.
>>>>>>>>
>>>>>>>> 555 timer.
>>>>>>>>
>>>>>>>> The "Design an accurate true power meter with a 555" challenge!
>>>>>>>>
>>>>>>>
>>>>>>> Can I use a few opamps too?
>>>>>>>
>>>>>>> A 555 could be used in a duty-cycle based multiplier. D.C. multipliers
>>>>>>> were popular for precision multiplies and divides and square roots
>>>>>>> once.
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> The LM324 or the '741, your choice! ;-)
>>>>>
>>>>> uA709?
>>>>>
>>>>>
>>>>
>>>> Probably allowed, IIRC it's older but better spec-ed than either, just
>>>> not internally compensated and not unity-gain stable without a bunch of
>>>> external parts...
>>>
>>> It made a decent comparator, uncompensated. But the NPN diff pair
>>> would zener, and it liked to latch up.
>>>
>>
>> The input stage isn't like anything I've seen before (i.e. modern) - two 
>> Darlington followers on either side of load resistors in the collectors 
>> of the LTP, fed by a constant voltage source.
>>
>> IIRC all op-amps that have resistive loads tied to the positive supply 
>> instead of current-mirror loads are prone to latch-up, for a technical 
>> reason that escapes me at the moment.
>>
>> Why they do it like that? Something about monolithic small-signal PNPs 
>> with good enough specs not being possible to lay down with the 
>> fabrication process available in '67 or something?
> 
> There's one PNP in the 709. Probably not a very good one. The slew
> rate is glacial, 0.25 volts per us.
> 
> There were some all-NPN opamps back then that were really awful.
> 
> At some point I decided to start using 741s, which was a
> million-dollar decision at the time. But prices dropped fast.
> 
> 

Until the mid to late '80s the only PNPs you could get on linear
processes were laterals.  Laterals have low beta and are super super
slow, but have some interesting features such as resisting reverse V_BE
out to 20V or something like that, vs. ~6V for a normal planar device.

To get speed out of those you had to restrict them to level shifting and
use capacitive coupling around them.  There was a trick for speeding up
LM301s and LM318s by capacitive coupling into the offset adjust or
frequency compensation pins.  It worked OK but made the frequency
compensation squirrelly, iirc.

The first complementary bipolar process I encountered was National's VIP
1 (Vertically Integrated PNP), which produced some nice parts,
especially the LM6361, which was fast and handled capacitive loads very
well.  (It's been discontinued but the LM8621 is similar.)

See e.g. <http://www.ti.com/lit/pdf/snoa843>.


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

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#450563

On Monday, March 6, 2017 at 11:10:23 AM UTC-8, bitrex wrote:

> The "Design an accurate true power meter with a 555" challenge!

So, a '555 mounted in an earring, or (for oldsters) on a tie clip, would
be appropriate.

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#450495

On 3/6/2017 12:25 PM, David Lesher wrote:
> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>
> ......"The inaccurate readings are attributed to the energy meter's
> design, together with the increasing use of modern (often
> energy-efficient) switching devices. Here, the electricity being
> consumed no longer has a perfect waveform, instead it acquires
> an erratic pattern. The designers of modern energy meters
> have not made sufficient allowance for switching devices of
> this kind. When they dismantled the energy meters tested, the
> researchers found that the ones associated with excessively high
> readings contained a 'Rogowski Coil' while those associated with
> excessively low readings contained a 'Hall Sensor'."
>
> I smell lawsuits since the PoCo's have been removing the
> old meters en mass....

I've got a house with a broken meter.  The old analog style, the big 
wheel doesn't turn anymore.  I guess after 50 years they wear out.  I 
wonder how many months of $5 utility bills it will take for them to 
figure it out?

-- 

Rick C

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#450498

On Monday, March 6, 2017 at 2:52:05 PM UTC-5, rickman wrote:
> On 3/6/2017 12:25 PM, David Lesher wrote:
> > <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
> >
> > ......"The inaccurate readings are attributed to the energy meter's
> > design, together with the increasing use of modern (often
> > energy-efficient) switching devices. Here, the electricity being
> > consumed no longer has a perfect waveform, instead it acquires
> > an erratic pattern. The designers of modern energy meters
> > have not made sufficient allowance for switching devices of
> > this kind. When they dismantled the energy meters tested, the
> > researchers found that the ones associated with excessively high
> > readings contained a 'Rogowski Coil' while those associated with
> > excessively low readings contained a 'Hall Sensor'."
> >
> > I smell lawsuits since the PoCo's have been removing the
> > old meters en mass....
> 
> I've got a house with a broken meter.  The old analog style, the big 
> wheel doesn't turn anymore.  I guess after 50 years they wear out.  I 
> wonder how many months of $5 utility bills it will take for them to 
> figure it out?
> 
> -- 
> 
> Rick C

Ahh I think you are responsible for the meter, at least I was.  
I had mine replaced last summer... mostly it was just the outside 
box rusting away.  (Maybe it was just the box I was responsible for...
anyway I'd call your local electrician.)  

George H. 

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#450501

On 3/6/2017 3:04 PM, George Herold wrote:
> On Monday, March 6, 2017 at 2:52:05 PM UTC-5, rickman wrote:
>> On 3/6/2017 12:25 PM, David Lesher wrote:
>>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>>
>>> ......"The inaccurate readings are attributed to the energy meter's
>>> design, together with the increasing use of modern (often
>>> energy-efficient) switching devices. Here, the electricity being
>>> consumed no longer has a perfect waveform, instead it acquires
>>> an erratic pattern. The designers of modern energy meters
>>> have not made sufficient allowance for switching devices of
>>> this kind. When they dismantled the energy meters tested, the
>>> researchers found that the ones associated with excessively high
>>> readings contained a 'Rogowski Coil' while those associated with
>>> excessively low readings contained a 'Hall Sensor'."
>>>
>>> I smell lawsuits since the PoCo's have been removing the
>>> old meters en mass....
>>
>> I've got a house with a broken meter.  The old analog style, the big
>> wheel doesn't turn anymore.  I guess after 50 years they wear out.  I
>> wonder how many months of $5 utility bills it will take for them to
>> figure it out?
>>
>> --
>>
>> Rick C
>
> Ahh I think you are responsible for the meter, at least I was.
> I had mine replaced last summer... mostly it was just the outside
> box rusting away.  (Maybe it was just the box I was responsible for...
> anyway I'd call your local electrician.)

Why?

-- 

Rick C

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#450503

George Herold wrote:


> Ahh I think you are responsible for the meter, at least I was.
> I had mine replaced last summer... mostly it was just the outside
> box rusting away.  (Maybe it was just the box I was responsible for...
> anyway I'd call your local electrician.)
The box, meter base, conduits and feed are the homeowner's responsibility.  
The meter, itself, is owned and maintained by the power company, and a seal 
is applied when it is installed.

Jon

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#450539

On Mon, 06 Mar 2017 14:28:08 -0600, Jon Elson <jmelson@wustl.edu>
wrote:

>George Herold wrote:
>
>
>> Ahh I think you are responsible for the meter, at least I was.
>> I had mine replaced last summer... mostly it was just the outside
>> box rusting away.  (Maybe it was just the box I was responsible for...
>> anyway I'd call your local electrician.)
>The box, meter base, conduits and feed are the homeowner's responsibility.  
>The meter, itself, is owned and maintained by the power company, and a seal 
>is applied when it is installed.
>
>Jon

We just got a nasty letter from PG&E. When we moved in here,
everything was rewired and one meter was left totally disconnected.
After 10 years, they got upset that we weren't paying for poweron that
one; there were no bills either.

They sent a guy out to put a seal on the knife switch that had no
wires going into it. They left the meter. I think they are happy now.



-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#450502

rickman wrote:


> 
> I've got a house with a broken meter.  The old analog style, the big
> wheel doesn't turn anymore.  I guess after 50 years they wear out.  I
> wonder how many months of $5 utility bills it will take for them to
> figure it out?
> 
Have a lawyer?  The power company will try to bill you for the estimated 
power consumption over the time the meter was broken.  They might even try 
to bill you for the maximum amount of power you could have possibly ever 
drawn givin you wire and transformer size.  I had a power company try to 
pull that on me, when I pointed out the reason the meter didn't work was 
that their lineman had connected the service wrong!

Jon

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#450505

On 03/06/2017 03:26 PM, Jon Elson wrote:
> rickman wrote:
>
>
>>
>> I've got a house with a broken meter.  The old analog style, the big
>> wheel doesn't turn anymore.  I guess after 50 years they wear out.  I
>> wonder how many months of $5 utility bills it will take for them to
>> figure it out?
>>
> Have a lawyer?  The power company will try to bill you for the estimated
> power consumption over the time the meter was broken.  They might even try
> to bill you for the maximum amount of power you could have possibly ever
> drawn givin you wire and transformer size.  I had a power company try to
> pull that on me, when I pointed out the reason the meter didn't work was
> that their lineman had connected the service wrong!
>
> Jon
>

Yeah, whenever I'm getting something for free that I should be paying 
for I don't automatically assume the company is simply going to write it 
off out of the goodness of their hearts when they figure it out.

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#450504

On 03/06/2017 02:52 PM, rickman wrote:
> On 3/6/2017 12:25 PM, David Lesher wrote:
>> <https://www.utwente.nl/en/news/!/2017/3/313543/electronic-energy-meters-false-readings-almost-six-times-higher-than-actual-energy-consumption>
>>
>>
>> ......"The inaccurate readings are attributed to the energy meter's
>> design, together with the increasing use of modern (often
>> energy-efficient) switching devices. Here, the electricity being
>> consumed no longer has a perfect waveform, instead it acquires
>> an erratic pattern. The designers of modern energy meters
>> have not made sufficient allowance for switching devices of
>> this kind. When they dismantled the energy meters tested, the
>> researchers found that the ones associated with excessively high
>> readings contained a 'Rogowski Coil' while those associated with
>> excessively low readings contained a 'Hall Sensor'."
>>
>> I smell lawsuits since the PoCo's have been removing the
>> old meters en mass....
>
> I've got a house with a broken meter.  The old analog style, the big
> wheel doesn't turn anymore.  I guess after 50 years they wear out.  I
> wonder how many months of $5 utility bills it will take for them to
> figure it out?
>

Even when they used analog meters around here back in the day instead of 
the WiFi ones or whatever they have now, I don't think they read the 
meter every month but often just billed on "estimated usage" by looking 
at a representative sample

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