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Groups > sci.electronics.equipment > #367 > unrolled thread

Error of % + digits?

Started by"Commander Kinsey" <CFKinsey@military.org.jp>
First post2020-06-18 14:03 +0100
Last post2020-06-24 20:03 +0000
Articles 20 on this page of 103 — 11 participants

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  Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 14:03 +0100
    Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 14:28 +0100
    Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-18 20:08 +0530
      Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 15:41 +0100
        Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-18 18:16 -0400
          Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-18 23:48 +0100
            Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-18 19:38 -0400
              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-19 21:46 +0100
                Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-19 18:55 -0400
                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-19 23:59 +0100
                    Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-20 12:09 +0530
                      Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-20 13:03 +0100
                        Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-20 11:24 -0400
                          Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-20 16:58 +0100
                            Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-20 23:28 +0530
                              Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-20 14:15 -0400
                                Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-06-20 23:54 +0100
                                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 05:10 +0000
                                  Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-26 11:27 -0400
                                    Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-27 06:40 +0000
                                      Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-27 09:55 -0400
                                        Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-29 02:59 +0000
                                          Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-29 10:54 -0400
                                            Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-30 03:28 +0000
                            Re: Error of % + digits? Jeroen Belleman <jeroen@nospam.please> - 2020-06-20 20:18 +0200
                              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-24 18:37 +0100
                            Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 04:54 +0000
                              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-11 21:38 +0100
                                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-13 03:21 +0000
                                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:32 +0100
                      Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-26 04:23 +0000
                        Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-06-26 14:02 +0530
                          Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-27 06:56 +0000
                        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-12 18:45 +0100
                          Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-12 23:31 +0530
                            Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-07-12 20:21 +0100
                              Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-13 10:23 +0530
                                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:36 +0100
                                  Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-13 20:57 +0530
                                    Re: Error of % + digits? Jeroen Belleman <jeroen@nospam.please> - 2020-07-13 17:39 +0200
                                      Re: Error of % + digits? Tom Gardner <spamjunk@blueyonder.co.uk> - 2020-07-13 21:04 +0100
                                        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-20 21:35 +0100
                                    Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-20 21:36 +0100
                                      Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-07-21 12:05 +0530
                                        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-31 23:53 +0100
                                          Re: Error of % + digits? Pimpom <nobody@nowhere.com> - 2020-08-01 14:31 +0530
                              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:35 +0100
                                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-16 07:30 +0000
                                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:19 +0100
                                    Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-21 01:13 +0000
                                      Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-08-04 22:27 +0100
                                        Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-09-09 07:39 +0000
                                  Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-17 12:15 +0000
                                    Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-28 19:02 +0100
                            Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-13 13:38 +0100
        Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-24 20:06 +0000
          Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-06-30 00:41 +0100
            Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-06-30 03:52 +0000
              Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-06-30 11:09 -0400
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-02 05:45 +0000
                  Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-02 07:03 +0000
                  Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-02 10:41 -0400
                    Re: Error of % + digits? RheillyPhoull <Rheilly@bigslong.com> - 2020-07-03 09:20 +0800
                      Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 20:09 +0100
                        Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 14:02 +0000
                          Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 19:16 +0100
                            Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 20:26 +0000
                              Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 21:44 +0100
                                Re: Separate amps jacks on multimeters Rich <rich@example.invalid> - 2020-07-17 22:37 +0000
                                  Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-18 00:11 +0100
                              Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 18:07 -0400
                                Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 23:31 +0100
                                  Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:10 -0400
                                    Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-18 00:18 +0100
                                      Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:30 -0400
                                        Re: Separate amps jacks on multimeters "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-28 22:16 +0100
                                    Re: Separate amps jacks on multimeters Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-22 04:24 +0000
                                      Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-22 12:28 -0400
                                  Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-17 19:25 -0400
                                Re: Separate amps jacks on multimeters Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-22 04:20 +0000
                                  Re: Separate amps jacks on multimeters Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-22 12:23 -0400
                    Re: Error of % + digits? Jasen Betts <jasen@xnet.co.nz> - 2020-07-03 13:10 +0000
                      Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-03 10:14 -0400
                    Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 20:10 +0100
                      Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 16:03 -0400
                        Re: Error of % + digits? Michael Terrell <terrell.michael.a@gmail.com> - 2020-07-16 13:13 -0700
                          Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:02 +0100
                            Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 23:29 -0400
                              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-24 22:09 +0100
                                Re: Error of % + digits? Rich <rich@example.invalid> - 2020-07-24 22:58 +0000
                                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-25 00:31 +0100
                        Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:01 +0100
                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:51 +0100
                    Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-26 03:53 +0000
                Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:45 +0100
                  Re: Error of % + digits? Ralph Mowery <rmowery28146@earthlink.net> - 2020-07-16 15:53 -0400
              Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-16 18:46 +0100
                Re: Error of % + digits? Michael Terrell <terrell.michael.a@gmail.com> - 2020-07-16 10:54 -0700
                  Re: Error of % + digits? "Commander Kinsey" <CFKinsey@military.org.jp> - 2020-07-17 00:15 +0100
                Re: Error of % + digits? Cydrome Leader <presence@MUNGEpanix.com> - 2020-07-26 04:17 +0000
            Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-30 07:59 +0000
    Re: Error of % + digits? Dieter Michel <dmichel@prosound.de> - 2020-06-22 17:19 +0200
    Re: Error of % + digits? Rich <rich@example.invalid> - 2020-06-24 20:03 +0000

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#479 — Re: Separate amps jacks on multimeters

FromRalph Mowery <rmowery28146@earthlink.net>
Date2020-07-22 12:23 -0400
SubjectRe: Separate amps jacks on multimeters
Message-ID<MPG.3982320cb2e4bbb989f7b@news.east.earthlink.net>
In reply to#477
In article <rf8eq6$brr$1@reader1.panix.com>, presence@MUNGEpanix.com 
says...
>  I do have a Fluke test meter that is purty much fool proof up to 600 
> > volts and rated CAT 4. A T1000.  It only measuers AC amps by passing a 
> > wire through the prongs.  It does have a switch for voltage and ohms.  I 
> > have on purpose set it to ohms and put it across a fuse in a 480 volt AC 
> > circuit to see if the fuse is good or bad.  No problem to do this. 
> 
> I just got one of those clamp current multimeters. I noticed some glaring 
> limitations vs the full out Fluke 87 V, but at the same time, it's way 
> more "idiot-proof".
> 
> The current ranges, even for DC at only available though the current 
> clamp. It's just not possible to short anything out with the test probes. 
> The downside (not really surprising) is no low current ranges. Ok fine. 
> The input impedance is pretty low at 1Meg as well, but for poking at line 
> voltage wiring, this is fine. Again, no matter what range you are set it, 
> it appears to be impossible to blow up the meter as it has no low 
> resistance across the leads modes. The ohms range seems to max out at 40k 
> or something surprisibly low like that, again, no big deal for prodding at 
> lighting circuits or an outlet, or some 24 volt circuit.
> 
> 

Meters like the T1000 are for quick go or no go test mainly.  For what 
they are mainly used for it does not make any differnece if they are off 
by even 10 %.  For quick tests  in an industrial enviroment it does not 
matter if the control voltage is 115.25 volts when anything from around 
110 to 130 volts is close enough.  Most circuits will have less than 
1000 ohms resistance , many of the motors will show up as an almoat 
short if the windings are good. Fuses are almost shorts or opens.  

The Fluke 87 and meters like that are more for electronic tests.  The 
specs on them are very good and will be accurate to one or two decimal 
places.  

When I worked I had access to almost any kind of meter or test set.  I 
often grabbed my Simpson 260 and analog Ampprobe for the equipment that 
would not start or run.  However I would stick the Fluke 'Bananna' in my 
pocket to check some things like the fuses in a power circuit.  

For the instruments where they needed to be measured to less than 1 % 
out came the fluke 87 or more likely a special piece of equipment that 
has a Heart interface.  That reads signals on the instrument lines.

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#409

FromJasen Betts <jasen@xnet.co.nz>
Date2020-07-03 13:10 +0000
Message-ID<rdnant$2sm$3@gonzo.revmaps.no-ip.org>
In reply to#407
On 2020-07-02, Ralph Mowery <rmowery28146@earthlink.net> wrote:
> In article <rdjsa6$28b$1@reader1.panix.com>, presence@MUNGEpanix.com 
> says...
>> 
>> Have you run this test with AC? That seems to be where the wheels come 
>> off. I brought up this thread to a friend and he mentioned his quest to 
>> repair some sort of HP true RMS meter that uses a thermocouple and heater 
>> to properly measure complex waveforms. I can't even guess how slow such a 
>> meter might be. 
>> 
>> > I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that 
>> > usually sell for around $ 5.  They seem to be reasonable accurate for 
>> > the money.  Plenty accurate for the home user to test things around the 
>> > house.  I do admit that the safety issue of putting them across the 120 
>> > or 240 volt power wires is somewhat doubtful.  I sure would not use one 
>> > where I worked to put across the 480 volt 3 phase system that is  fused 
>> > with 200 amps.
>> 
>> I'm pretty timid with anything upstream from a plain outlet. I had an 
>> edison base fuse burst in my hand once. Never seen one come apart before. 
>> It was just a 120v lighting circuit, but right off the service panel. 
>> There's way more excitement near those things.
>> 
>
> I have not ran any tests for AC . The things I work with don't care 
> about very much about being accurate to more than around 5 %.  Usually 
> it is more of do I have a voltage/current or not.
>
> When I work on most anything other than low voltage (below 100 volts) I 
> ues either my Simpson 260 analog meter  or a Fluke meter that is rated 
> for cat 3 and 4.  If you have not heard of the Cat numbers, they are for 
> devices used in different power circuits.  I don't know the numbers off 
> hand, but it goes something like this, Cat 1 is for low voltage items, 
> Cat 2 for things like stoves and refrigerators, Cat 3 for homw 
> wiring,and Cat 4 for the very high power circuits like I often worked on 
> like the 480 volt AC and 300 amps.
>
> For a real scare you should see some of the safety movies that Fluke put 
> out.  They show under test conditions what can hapen to inexpensive 
> meters and their meters under different conditions  like having the 
> meter set for amps and putting across a 480 volt circuit that has plenty 
> of amps .  

or even just this document.

https://content.fluke.com/promotions/promo-dmm/0518-dmm-campaign/dmm/fluke_dmm-chfr/files/safetyguidelines.pdf

-- 
  Jasen.

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#410

FromRalph Mowery <rmowery28146@earthlink.net>
Date2020-07-03 10:14 -0400
Message-ID<MPG.3969072f418730ef989f41@news.east.earthlink.net>
In reply to#409
In article <rdnant$2sm$3@gonzo.revmaps.no-ip.org>, jasen@xnet.co.nz 
says...
> 
> > I have not ran any tests for AC . The things I work with don't care 
> > about very much about being accurate to more than around 5 %.  Usually 
> > it is more of do I have a voltage/current or not.
> >
> 
> 

Just for the fun of it, I did test the 3 'free' Harbor Freight meters on 
AC and DC yeaterday.  From 0 to 25 VDC the HF meters were within about 
.5 % of the Fluke meter.  On AC up to 130 VAC they were around 3 %.  One 
was always low and the other 2 were always high.

So they are accurate for most anything around the house for most people.

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#451

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-16 20:10 +0100
Message-ID<op.0nu3kdf9wdg98l@glass>
In reply to#407
On Thu, 02 Jul 2020 15:41:19 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:

> In article <rdjsa6$28b$1@reader1.panix.com>, presence@MUNGEpanix.com
> says...
>>
>> Have you run this test with AC? That seems to be where the wheels come
>> off. I brought up this thread to a friend and he mentioned his quest to
>> repair some sort of HP true RMS meter that uses a thermocouple and heater
>> to properly measure complex waveforms. I can't even guess how slow such a
>> meter might be.
>>
>> > I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that
>> > usually sell for around $ 5.  They seem to be reasonable accurate for
>> > the money.  Plenty accurate for the home user to test things around the
>> > house.  I do admit that the safety issue of putting them across the 120
>> > or 240 volt power wires is somewhat doubtful.  I sure would not use one
>> > where I worked to put across the 480 volt 3 phase system that is  fused
>> > with 200 amps.
>>
>> I'm pretty timid with anything upstream from a plain outlet. I had an
>> edison base fuse burst in my hand once. Never seen one come apart before.
>> It was just a 120v lighting circuit, but right off the service panel.
>> There's way more excitement near those things.
>>
>>
>
> I have not ran any tests for AC . The things I work with don't care
> about very much about being accurate to more than around 5 %.  Usually
> it is more of do I have a voltage/current or not.
>
> When I work on most anything other than low voltage (below 100 volts) I
> ues either my Simpson 260 analog meter  or a Fluke meter that is rated
> for cat 3 and 4.  If you have not heard of the Cat numbers, they are for
> devices used in different power circuits.

Yes I've heard of them, they're a measurement scale for pansies.

> I don't know the numbers off
> hand, but it goes something like this, Cat 1 is for low voltage items,
> Cat 2 for things like stoves and refrigerators, Cat 3 for homw
> wiring,and Cat 4 for the very high power circuits like I often worked on
> like the 480 volt AC and 300 amps.
>
> For a real scare you should see some of the safety movies that Fluke put
> out.  They show under test conditions what can hapen to inexpensive
> meters and their meters under different conditions  like having the
> meter set for amps and putting across a 480 volt circuit that has plenty
> of amps .

Safety movies designed to sell Fluke meters, and you fell for them hook line and sinker.

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#453

FromRalph Mowery <rmowery28146@earthlink.net>
Date2020-07-16 16:03 -0400
Message-ID<MPG.397a7c87fde57852989f67@news.east.earthlink.net>
In reply to#451
In article <op.0nu3kdf9wdg98l@glass>, CFKinsey@military.org.jp says...
> 
> Safety movies designed to sell Fluke meters, and you fell for them hook line and sinker.
> 
> 

No, I have actually seen a few blowups and the results of some others.

Have you ever worked at a place that has lots of 480 volt 3 phase 
equipment ?  I did before retiring.  One learns to respect what can 
hapen.  

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#454

FromMichael Terrell <terrell.michael.a@gmail.com>
Date2020-07-16 13:13 -0700
Message-ID<093fe64d-387b-4495-91ea-0b4727b2afe9o@googlegroups.com>
In reply to#453
He is just an arc flash away from making an ash of himself.

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#456

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-17 00:02 +0100
Message-ID<op.0nvd9pimwdg98l@glass>
In reply to#454
On Thu, 16 Jul 2020 21:13:11 +0100, Michael Terrell <terrell.michael.a@gmail.com> wrote:

> He is just an arc flash away from making an ash of himself.

I've done that actually, just scorched my hand for a couple of weeks.

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#459

FromRalph Mowery <rmowery28146@earthlink.net>
Date2020-07-16 23:29 -0400
Message-ID<MPG.397ae528eb38aa3b989f6c@news.east.earthlink.net>
In reply to#456
In article <op.0nvd9pimwdg98l@glass>, CFKinsey@military.org.jp says...
> 
> > He is just an arc flash away from making an ash of himself.
> 
> I've done that actually, just scorched my hand for a couple of weeks.
> 
> 

If you had respected things that probably would never hapen, you would 
not have scorched your hand.  

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#481

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-24 22:09 +0100
Message-ID<op.0n92d5rdwdg98l@glass>
In reply to#459
On Fri, 17 Jul 2020 04:29:38 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:

> In article <op.0nvd9pimwdg98l@glass>, CFKinsey@military.org.jp says...
>>
>> > He is just an arc flash away from making an ash of himself.
>>
>> I've done that actually, just scorched my hand for a couple of weeks.
>
> If you had respected things that probably would never hapen, you would
> not have scorched your hand.

You miss the point, it's not the end of the world.

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#482

FromRich <rich@example.invalid>
Date2020-07-24 22:58 +0000
Message-ID<rffp31$j02$3@dont-email.me>
In reply to#481
Commander Kinsey <CFKinsey@military.org.jp> wrote:
> On Fri, 17 Jul 2020 04:29:38 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:
> 
>> In article <op.0nvd9pimwdg98l@glass>, CFKinsey@military.org.jp says...
>>>
>>> > He is just an arc flash away from making an ash of himself.
>>>
>>> I've done that actually, just scorched my hand for a couple of weeks.
>>
>> If you had respected things that probably would never hapen, you would
>> not have scorched your hand.
> 
> You miss the point, it's not the end of the world.

A scorched hand, no, not the end of the world.

A stopped heart, which *can* happen if the arc flash conducts enough 
current through the wrong part of the body, well then for the one who's 
heart just got stopped it might just be the end of the world.

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#483

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-25 00:31 +0100
Message-ID<op.0n98x1s9wdg98l@glass>
In reply to#482
On Fri, 24 Jul 2020 23:58:41 +0100, Rich <rich@example.invalid> wrote:

> Commander Kinsey <CFKinsey@military.org.jp> wrote:
>> On Fri, 17 Jul 2020 04:29:38 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:
>>
>>> In article <op.0nvd9pimwdg98l@glass>, CFKinsey@military.org.jp says...
>>>>
>>>> > He is just an arc flash away from making an ash of himself.
>>>>
>>>> I've done that actually, just scorched my hand for a couple of weeks.
>>>
>>> If you had respected things that probably would never hapen, you would
>>> not have scorched your hand.
>>
>> You miss the point, it's not the end of the world.
>
> A scorched hand, no, not the end of the world.
>
> A stopped heart, which *can* happen if the arc flash conducts enough
> current through the wrong part of the body, well then for the one who's
> heart just got stopped it might just be the end of the world.

It seldom travels that path.

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#455

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-17 00:01 +0100
Message-ID<op.0nvd83mawdg98l@glass>
In reply to#453
On Thu, 16 Jul 2020 21:03:04 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:

> In article <op.0nu3kdf9wdg98l@glass>, CFKinsey@military.org.jp says...
>>
>> Safety movies designed to sell Fluke meters, and you fell for them hook line and sinker.
>>
>>
>
> No, I have actually seen a few blowups and the results of some others.
>
> Have you ever worked at a place that has lots of 480 volt 3 phase
> equipment ?

Yes.

> I did before retiring.  One learns to respect what can hapen.

I've seen what happens when you connect two phases to one phase equipment, it's quite amusing.

And I don't respect things that will probably never happen.

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#448

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-16 18:51 +0100
Message-ID<op.0nuzwne1wdg98l@glass>
In reply to#405
On Thu, 02 Jul 2020 06:45:42 +0100, Cydrome Leader <presence@mungepanix.com> wrote:

> In sci.electronics.equipment Ralph Mowery <rmowery28146@earthlink.net> wrote:
>> In article <rdecuc$m73$1@reader1.panix.com>, presence@MUNGEpanix.com
>> says...
>>>
>>> > So should I assume the cheaper ones are lying?  Or have they just made a rough estimate adding the two errors?
>>>
>>> might be both. I dug out my first DMM, a Wavetek DM2, circa 1990s. It might
>>> have been from a raffle or something like that.
>>>
>>> The DC voltage specs range from 0.8% +1 digit (not bad really)  over to the
>>> AC ranges which are "1.2% RDG +10 Digits". If I had new leads, I'd trust it
>>> with outlet voltage, but would stay away from 208volts. The meter has 3.5
>>> digits or max display of 1999. I'm figuring a real 100volt AC reading could
>>> be 99 to 101 plus another error of +/- 1 volt for the 10 digits tolerance
>>> on the display or count. so 100volts from your Japanese outlet reference
>>> might read 98 to 102 volts. So while in the ballpark, it's better than you
>>> can read off a Simpson 260 meter in the AC voltage range. I could be wrong
>>> on this too.
>>>
>>> It's a pretty decent meter for poking at DC circuits for the tens of
>>> dollars is must have cost when new.
>>>
>>>
>>
>> It seems that maybe due to modern manufactoring the meters are more
>> accurate than they were 20 years ago.  I bought some DC voltmeters from
>> China.  They display 3 digits.  They read from 0 to 99.9 volts.  I coulg
>> get 4 of them for less than $ 15 including the shipping.  I hooked all 4
>> of them in parallel with a Fluke 87 .  Three of them tracked right along
>> with the Fluke with the last digit sometimes being one high or low from
>> 0 to 24 volts.  The fourth one was off by an average of 2 on the last
>> digit.  I found an adjustment screw on the back of the meter and tweaked
>> it and re ran the test.  It then fell in line with the other meters.
>
> Have you run this test with AC? That seems to be where the wheels come
> off. I brought up this thread to a friend and he mentioned his quest to
> repair some sort of HP true RMS meter that uses a thermocouple and heater
> to properly measure complex waveforms. I can't even guess how slow such a
> meter might be.

How well do these things work measuring dodgy waves like from a cheap UPS or invertor?

>> I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that
>> usually sell for around $ 5.  They seem to be reasonable accurate for
>> the money.  Plenty accurate for the home user to test things around the
>> house.  I do admit that the safety issue of putting them across the 120
>> or 240 volt power wires is somewhat doubtful.  I sure would not use one
>> where I worked to put across the 480 volt 3 phase system that is  fused
>> with 200 amps.
>
> I'm pretty timid with anything upstream from a plain outlet.

I've replaced outlets (240V, not the namby pamby USA stuff) without turning off the power - other outlets on the same circuit were being used in the office and I saw no point in interrupting them.

Just keep your fingers off the metal things and don't short stuff together.  Wear goggles and gloves if you want to be a girl about it.

> I had an
> edison base fuse burst in my hand once. Never seen one come apart before.
> It was just a 120v lighting circuit, but right off the service panel.
> There's way more excitement near those things.

Try shorting two phases together with 500A cables.  That causes lots of smoke, a fire alarm, 3 fire engines, and a visit from the power company.  Do not ever employ Irish electricians.

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#484

FromCydrome Leader <presence@MUNGEpanix.com>
Date2020-07-26 03:53 +0000
Message-ID<rfiun4$n7$3@reader1.panix.com>
In reply to#448
In sci.electronics.basics Commander Kinsey <CFKinsey@military.org.jp> wrote:
> On Thu, 02 Jul 2020 06:45:42 +0100, Cydrome Leader <presence@mungepanix.com> wrote:
> 
>> In sci.electronics.equipment Ralph Mowery <rmowery28146@earthlink.net> wrote:
>>> In article <rdecuc$m73$1@reader1.panix.com>, presence@MUNGEpanix.com
>>> says...
>>>>
>>>> > So should I assume the cheaper ones are lying?  Or have they just made a rough estimate adding the two errors?
>>>>
>>>> might be both. I dug out my first DMM, a Wavetek DM2, circa 1990s. It might
>>>> have been from a raffle or something like that.
>>>>
>>>> The DC voltage specs range from 0.8% +1 digit (not bad really)  over to the
>>>> AC ranges which are "1.2% RDG +10 Digits". If I had new leads, I'd trust it
>>>> with outlet voltage, but would stay away from 208volts. The meter has 3.5
>>>> digits or max display of 1999. I'm figuring a real 100volt AC reading could
>>>> be 99 to 101 plus another error of +/- 1 volt for the 10 digits tolerance
>>>> on the display or count. so 100volts from your Japanese outlet reference
>>>> might read 98 to 102 volts. So while in the ballpark, it's better than you
>>>> can read off a Simpson 260 meter in the AC voltage range. I could be wrong
>>>> on this too.
>>>>
>>>> It's a pretty decent meter for poking at DC circuits for the tens of
>>>> dollars is must have cost when new.
>>>>
>>>>
>>>
>>> It seems that maybe due to modern manufactoring the meters are more
>>> accurate than they were 20 years ago.  I bought some DC voltmeters from
>>> China.  They display 3 digits.  They read from 0 to 99.9 volts.  I coulg
>>> get 4 of them for less than $ 15 including the shipping.  I hooked all 4
>>> of them in parallel with a Fluke 87 .  Three of them tracked right along
>>> with the Fluke with the last digit sometimes being one high or low from
>>> 0 to 24 volts.  The fourth one was off by an average of 2 on the last
>>> digit.  I found an adjustment screw on the back of the meter and tweaked
>>> it and re ran the test.  It then fell in line with the other meters.
>>
>> Have you run this test with AC? That seems to be where the wheels come
>> off. I brought up this thread to a friend and he mentioned his quest to
>> repair some sort of HP true RMS meter that uses a thermocouple and heater
>> to properly measure complex waveforms. I can't even guess how slow such a
>> meter might be.
> 
> How well do these things work measuring dodgy waves like from a cheap UPS or invertor?

Probably perfectly.
 
>>> I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that
>>> usually sell for around $ 5.  They seem to be reasonable accurate for
>>> the money.  Plenty accurate for the home user to test things around the
>>> house.  I do admit that the safety issue of putting them across the 120
>>> or 240 volt power wires is somewhat doubtful.  I sure would not use one
>>> where I worked to put across the 480 volt 3 phase system that is  fused
>>> with 200 amps.
>>
>> I'm pretty timid with anything upstream from a plain outlet.
> 
> I've replaced outlets (240V, not the namby pamby USA stuff) without 
> turning off the power - other outlets on the same circuit were being 
> used in the office and I saw no point in interrupting them.

cool story.

> Just keep your fingers off the metal things and don't short stuff together.  Wear goggles and gloves if you want to be a girl about it.
> 
>> I had an
>> edison base fuse burst in my hand once. Never seen one come apart before.
>> It was just a 120v lighting circuit, but right off the service panel.
>> There's way more excitement near those things.
> 
> Try shorting two phases together with 500A cables.  That causes lots of 
> smoke, a fire alarm, 3 fire engines, and a visit from the power company.  
> Do not ever employ Irish electricians.

In America we have fuses and circuit breakers. Check youtube for a video 
about how they work.

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#446

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-16 18:45 +0100
Message-ID<op.0nuzmdi9wdg98l@glass>
In reply to#404
On Tue, 30 Jun 2020 16:09:46 +0100, Ralph Mowery <rmowery28146@earthlink.net> wrote:

> In article <rdecuc$m73$1@reader1.panix.com>, presence@MUNGEpanix.com
> says...
>>
>> > So should I assume the cheaper ones are lying?  Or have they just made a rough estimate adding the two errors?
>>
>> might be both. I dug out my first DMM, a Wavetek DM2, circa 1990s. It might
>> have been from a raffle or something like that.
>>
>> The DC voltage specs range from 0.8% +1 digit (not bad really)  over to the
>> AC ranges which are "1.2% RDG +10 Digits". If I had new leads, I'd trust it
>> with outlet voltage, but would stay away from 208volts. The meter has 3.5
>> digits or max display of 1999. I'm figuring a real 100volt AC reading could
>> be 99 to 101 plus another error of +/- 1 volt for the 10 digits tolerance
>> on the display or count. so 100volts from your Japanese outlet reference
>> might read 98 to 102 volts. So while in the ballpark, it's better than you
>> can read off a Simpson 260 meter in the AC voltage range. I could be wrong
>> on this too.
>>
>> It's a pretty decent meter for poking at DC circuits for the tens of
>> dollars is must have cost when new.
>
> It seems that maybe due to modern manufactoring the meters are more
> accurate than they were 20 years ago.  I bought some DC voltmeters from
> China.  They display 3 digits.  They read from 0 to 99.9 volts.  I coulg
> get 4 of them for less than $ 15 including the shipping.  I hooked all 4
> of them in parallel with a Fluke 87 .  Three of them tracked right along
> with the Fluke with the last digit sometimes being one high or low from
> 0 to 24 volts.  The fourth one was off by an average of 2 on the last
> digit.  I found an adjustment screw on the back of the meter and tweaked
> it and re ran the test.  It then fell in line with the other meters.
>
> I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that
> usually sell for around $ 5.  They seem to be reasonable accurate for
> the money.  Plenty accurate for the home user to test things around the
> house.  I do admit that the safety issue of putting them across the 120
> or 240 volt power wires is somewhat doubtful.  I sure would not use one
> where I worked to put across the 480 volt 3 phase system that is  fused
> with 200 amps.

Whyever not?  Even the cheap ones usually state you can use them up to 1000 volts.  I've used them on 240 and 415 just fine.  I used one on 2000 volts once, and it just failed inside, not even smoke or noise.

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#452

FromRalph Mowery <rmowery28146@earthlink.net>
Date2020-07-16 15:53 -0400
Message-ID<MPG.397a7a159b6983c8989f66@news.east.earthlink.net>
In reply to#446
In article <op.0nuzmdi9wdg98l@glass>, CFKinsey@military.org.jp says...
>  I had 3 or 4 of the Harbor Freight 'free' multimeters.  The ones that
> > usually sell for around $ 5.  They seem to be reasonable accurate for
> > the money.  Plenty accurate for the home user to test things around the
> > house.  I do admit that the safety issue of putting them across the 120
> > or 240 volt power wires is somewhat doubtful.  I sure would not use one
> > where I worked to put across the 480 volt 3 phase system that is  fused
> > with 200 amps.
> 
> Whyever not?  Even the cheap ones usually state you can use them up to 1000 volts.  I've used them on 240 and 415 just fine.  I used one on 2000 volts once, and it just failed inside, not even smoke or noise.
> 
> 

Because I have seen what damage can be done with those circuits.

I have also seen some safty films that the Fluke meter company put out.  
Say you take your HF meter and by mistake have it on the ohms or amp 
range.  Normally an internal fuse would blow.  However there is enough 
power in the circuits to arc over the fuse, the meter leads instantly 
almost explode or look like an arc welder.  If you have one hand on each 
lead it is possiable the insulation will melt off and maybe into your 
hands.  You could also become part of the circuit and fry.

Look here around the 6 minuit point.

https://www.youtube.com/watch?v=OEoazQ1zuUM

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#447

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-16 18:46 +0100
Message-ID<op.0nuzn8rjwdg98l@glass>
In reply to#402
On Tue, 30 Jun 2020 04:52:44 +0100, Cydrome Leader <presence@mungepanix.com> wrote:

> In sci.electronics.equipment Commander Kinsey <CFKinsey@military.org.jp> wrote:
>> On Wed, 24 Jun 2020 21:06:04 +0100, Rich <rich@example.invalid> wrote:
>>
>>> In sci.electronics.equipment Commander Kinsey <CFKinsey@military.org.jp> wrote:
>>>> On Thu, 18 Jun 2020 15:38:46 +0100, Pimpom <nobody@nowhere.com> wrote:
>>>>
>>>>> On 6/18/2020 6:33 PM, Commander Kinsey wrote:
>>>>>> I just bought an amp clamp meter, and it states the error is "+/-
>>>>>> 1.9% + 3 digits".  What does the "3 digits" part mean?
>>>>>>
>>>>>
>>>>> If your meter should read, say 1.875 A, the correct reading could
>>>>> be anywhere from 1.872 to 1.878. This is a possible error in the
>>>>> display presented to you in the analog-digital display conversion
>>>>> process. The +/-1.9% possible error is about the measurement
>>>>> taken including - but not only - any error made by the sensor.
>>>>
>>>> Thanks, I wonder why all my other meters only list a % error.  Is it
>>>> included within it somehow, or are they just lying, or do some meters
>>>> not have this error?
>>>
>>> One generally finds the percentage plus digits error measures on more
>>> expensive equipment.  Less expensive equipment more often than not only
>>> lists a percentage and nothing more.
>>
>> So should I assume the cheaper ones are lying?  Or have they just made a rough estimate adding the two errors?
>
> might be both. I dug out my first DMM, a Wavetek DM2, circa 1990s. It might
> have been from a raffle or something like that.
>
> The DC voltage specs range from 0.8% +1 digit (not bad really)  over to the
> AC ranges which are "1.2% RDG +10 Digits".

TEN!?  Surely that's more than the number of digits it has?  In which case it has no accuracy at all.

> If I had new leads, I'd trust it
> with outlet voltage, but would stay away from 208volts.

You oughta complain about that low voltage.  Some equipment needs at least 220.

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#449

FromMichael Terrell <terrell.michael.a@gmail.com>
Date2020-07-16 10:54 -0700
Message-ID<939f3cd0-88a8-4dd5-8069-ee27fa2c8377o@googlegroups.com>
In reply to#447
208 is a standard three phase voltage. It is three 120 volt lines phased 120 degrees apart.

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#457

From"Commander Kinsey" <CFKinsey@military.org.jp>
Date2020-07-17 00:15 +0100
Message-ID<op.0nvevzhlwdg98l@glass>
In reply to#449
On Thu, 16 Jul 2020 18:54:08 +0100, Michael Terrell <terrell.michael.a@gmail.com> wrote:

> 208 is a standard three phase voltage. It is three 120 volt lines phased 120 degrees apart.

Ah, I didn't know that existed.  I thought you only got 120 when you centre tapped a single 240.  If you're gonna use three phase, wouldn't you want more voltage?

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#485

FromCydrome Leader <presence@MUNGEpanix.com>
Date2020-07-26 04:17 +0000
Message-ID<rfj04q$3mf$1@reader1.panix.com>
In reply to#447
In sci.electronics.basics Commander Kinsey <CFKinsey@military.org.jp> wrote:
> On Tue, 30 Jun 2020 04:52:44 +0100, Cydrome Leader <presence@mungepanix.com> wrote:
> 
>> In sci.electronics.equipment Commander Kinsey <CFKinsey@military.org.jp> wrote:
>>> On Wed, 24 Jun 2020 21:06:04 +0100, Rich <rich@example.invalid> wrote:
>>>
>>>> In sci.electronics.equipment Commander Kinsey <CFKinsey@military.org.jp> wrote:
>>>>> On Thu, 18 Jun 2020 15:38:46 +0100, Pimpom <nobody@nowhere.com> wrote:
>>>>>
>>>>>> On 6/18/2020 6:33 PM, Commander Kinsey wrote:
>>>>>>> I just bought an amp clamp meter, and it states the error is "+/-
>>>>>>> 1.9% + 3 digits".  What does the "3 digits" part mean?
>>>>>>>
>>>>>>
>>>>>> If your meter should read, say 1.875 A, the correct reading could
>>>>>> be anywhere from 1.872 to 1.878. This is a possible error in the
>>>>>> display presented to you in the analog-digital display conversion
>>>>>> process. The +/-1.9% possible error is about the measurement
>>>>>> taken including - but not only - any error made by the sensor.
>>>>>
>>>>> Thanks, I wonder why all my other meters only list a % error.  Is it
>>>>> included within it somehow, or are they just lying, or do some meters
>>>>> not have this error?
>>>>
>>>> One generally finds the percentage plus digits error measures on more
>>>> expensive equipment.  Less expensive equipment more often than not only
>>>> lists a percentage and nothing more.
>>>
>>> So should I assume the cheaper ones are lying?  Or have they just made a rough estimate adding the two errors?
>>
>> might be both. I dug out my first DMM, a Wavetek DM2, circa 1990s. It might
>> have been from a raffle or something like that.
>>
>> The DC voltage specs range from 0.8% +1 digit (not bad really)  over to the
>> AC ranges which are "1.2% RDG +10 Digits".
> 
> TEN!?  Surely that's more than the number of digits it has?  In which case it has no accuracy at all.

I'm pretty sure they mean 10 counts which could be 1 volt on a scale with 
1 decimal place. That does sound terrible if there were no decimal places 
though.
 
>> If I had new leads, I'd trust it
>> with outlet voltage, but would stay away from 208volts.
> 
> You oughta complain about that low voltage.  Some equipment needs at 
> least 220.

terribly designed equiment, maybe. 208 is standard voltage for phase to 
phase in a three wire systems, as used in a commercial setting in the US.

minilabs, for processing 35mm film fall into the stupid design category, 
usually being speced for 120 or 240 at dozens of amps.

Nobody runs a fucking minilab in their home, and it makes no sense to run 
30+amp 120volt service anyways. So, in any place that would have a 
minilab, they're going to have 208, not 120 or 240. So the result is boost 
transformer has to be installed. They're not large, being rated only for 
the KVA of the voltage boost, but it's still dumb.

It's just shitty lazy design, where maybe they can strap two heating 
elements in series for 240 and parallel them for 120, but again, nobody 
uses machines like that in their home where split phase power is available 
anyways. 

The better designed machines won't have resisitve heating elements that 
burn out at 240 and still have motors that will start and run fine on 208.

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