20 19:15
À : Discussion of precise time and frequency measurement
Objet : Re: [time-nuts] Power glitch - Sat morning
Would a time nut in Europe in a typical single family home have access to all
three phases ?
If so would there be any benefit to monitoring the frequency of each phase ?
Mark Sp
> (I recall that correct wiring of the phases / phase rotation was very
> important vis a vis backup power sources for data centres.)
For anything but resitive heating, you 100% want to have the order
of your three phases under tight control (said the 14 year old kid
who fixed the fraye
Yes that makes sense. I suppose from a power quality perspective there might
be some benefit in monitoring all three phases but probably not from a time
nuts point of view.
(I recall that correct wiring of the phases / phase rotation was very important
vis a vis backup power sources for data
On Wed, Apr 1, 2020 at 6:49 PM Arnold Tibus wrote:
> > If so would there be any benefit to monitoring the frequency of each
> phase ?
>
> No, because the 3 phases are generated and provided via 3phase
> transformers in the village together (fixed 120°)!
>
>
The effect on a large machine if the 3
Hello timenuts,
just a quick answer from a standard user in DL (living in private house):
Am 01.04.2020 um 19:14 schrieb Mark Spencer:
Would a time nut in Europe in a typical single family home have access to all
three phases ?
In general, Yes!
At the house entry there are always the 3 phases
Here in UK, no.
It's available at extra installation cost and some people with a big lathe
or other machinery have it as do farms and industrial locations. But the
typical domestic house doesn't : phases are commonly distributed down the
street with progressive phases on each property.
On Wed, A
In message <29d5bd66-0d7e-4961-8532-6e4a0e361...@alignedsolutions.com>, Mark
Spencer writes:
>Would a time nut in Europe in a typical single family home have access to all
>three phases ?
At least here in Denmark: Yes.
Small houses which got electrified 100 years ago may only have
Would a time nut in Europe in a typical single family home have access to all
three phases ?
If so would there be any benefit to monitoring the frequency of each phase ?
Mark Spencer
m...@alignedsolutions.com
604 762 4099
> On Apr 1, 2020, at 9:50 AM, Poul-Henning Kamp wrote:
>
>
In message <3b7684a9-2702-295b-4935-33a9b3f47...@earthlink.net>, jimlux writes:
>In EU, where 240V is the default line voltage, I wonder what the 3 phase
>distribution is? Is it 415 delta / 240 star
230V actually, and yes, it is universally 400 delta / 230 star.
That's also why you on
On 4/1/20 8:13 AM, Didier Juges wrote:
When you feed an electrical moteur with that, it sounds like a Harley
Davidson :)
It's a feature!
Only if the motor is 2 phase, also.
208 delta/120 star(wye) is a very common distribution scheme in "light
industrial/office" applications. Most of the lo
When you feed an electrical moteur with that, it sounds like a Harley
Davidson :)
It's a feature!
On Tue, Mar 31, 2020, 10:58 AM Mark Spencer
wrote:
> A few decades ago I was chatting with an electrical engineer during some
> down time during a long project in Canada. We started talking about
>
Hi
At some point the rational question would be - how does this relate to timing?
Getting a sound card so that it will do a reasonable job of time tagging edges
can be “fun”. My approach was always to feed a “known” signal into that second
channel …..
Bob
> On Mar 31, 2020, at 8:46 PM, Hal Mur
azelio.bori...@gmail.com said:
> It helps to have a digitizer on the line, a 'scope to sample the line, say,
> 20 seconds before and 20 second after a glitch. This way you can surely tell
> what happened without any speculation. There are a number of ready made
> digitizers (red-pitaya, digilent
A few decades ago I was chatting with an electrical engineer during some down
time during a long project in Canada. We started talking about residential AC
power.
Reportedly in some multi tenant buildings in Canada the individual suites may
be supplied with two phases from a 208 / 120 volt
aged appliances.
> Sent: Tuesday, March 31, 2020 at 11:26 AM
> From: "Bob kb8tq"
> To: ch...@chriscaudle.org, "Discussion of precise time and frequency
> measurement"
> Subject: Re: [time-nuts] Power glitch - Sat morning
>
> Hi
>
> I agree that it
Hi
I agree that it shouldn’t be something that happens. That’s why half the house
going dark was a bit weird …..
Bob
> On Mar 31, 2020, at 10:53 AM, Chris Caudle wrote:
>
> On Tue, March 31, 2020 8:28 am, Bob kb8tq wrote:
>> If you have a two phase circuit, are both phases of interest?
>
> If
On Tue, March 31, 2020 8:28 am, Bob kb8tq wrote:
> If you have a two phase circuit, are both phases of interest?
If you are referring to residential power, a single how would be single
phase center-tapped, as far as I know you never get two phases to a single
residence. The houses in a neighborho
Hi
One minor point:
If you *do* decide to digitize the line, think about how much headroom you want
on the digitizer. That applies both in the amplitude and time domains. On a 120V
60 Hz line, is an 800V 300 us pulse of interest? How about a half cycle at 2X
or
(1/4) line voltage?
If you hav
Hal, were there any storms or maybe just drenching rain in your area
Saturday AM? Fallen trees, drooping branches, and line crosses all go
together.
5 seconds is a very common value for circuit breaker reclosers as faults
either clear themselves or are isolated.
Tim N3QE
On Tue, Mar 31, 2020 at
It helps to have a digitizer on the line, a 'scope to sample the line,
say, 20 seconds before and 20 second after a glitch. This way you can
surely tell what happened without any speculation. There are a number
of ready made digitizers (red-pitaya, digilent analog discovery, ...)
if you don't want
A while ago, I clean things up so that my system that monitors the line
frequency was running off a UPS while watching the non-UPS line. I looked at
some graphs. It seemed to be working. I moved on to other things.
Last Sat morning, it got tested. Here is the graph of that area:
http://us
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