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-   -   Specification of current reading on multimeter (https://www.diybanter.com/electronics-repair/268037-specification-current-reading-multimeter.html)

nicola January 3rd 09 01:18 PM

Specification of current reading on multimeter
 
I am in the UK. I have a £20 digital multimeter and would like
some advice. The meter is a Maplin model PG10B (order code GW18U)

http://www.maplin.co.uk/Module.aspx?ModuleNo=4402

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?

(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
Current measurement?

(Q3) Isn't that figure of 200 mV rather high? I mean, if I use
the 2 mA or 20 mA scale in an electronics circuit powered by a 1.5
volt cell then a 200 mV drop in the circuit is very significant.

-----

My real need is to measure current while charging a AAA NiMH cell.

When I set my multimeter to measure DC Current and insert it in
the circuit, the charger's light fails to come on!

It's as if the prescence of the meter is disturbing the circuit
too much.

The voltage of my uncharged cell might typically be 1.1 volts and
the charger says it delivers up to about 120 mA.

(Q4) Is my multimeter simply too low-spec to measure current in
this application?

nikk

Phil Allison January 3rd 09 01:26 PM

Specification of current reading on multimeter
 

"nicola"
I am in the UK. I have a £20 digital multimeter and would like
some advice. The meter is a Maplin model PG10B (order code GW18U)

http://www.maplin.co.uk/Module.aspx?ModuleNo=4402

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?



** Yep.


(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
Current measurement?


** Yep.

(Q3) Isn't that figure of 200 mV rather high?



** Nope.


I mean, if I use
the 2 mA or 20 mA scale in an electronics circuit powered by a 1.5
volt cell then a 200 mV drop in the circuit is very significant.



** Could be.


My real need is to measure current while charging a AAA NiMH cell.

When I set my multimeter to measure DC Current and insert it in
the circuit, the charger's light fails to come on!

It's as if the prescence of the meter is disturbing the circuit
too much.



** Could very well be.


The voltage of my uncharged cell might typically be 1.1 volts and
the charger says it delivers up to about 120 mA.

(Q4) Is my multimeter simply too low-spec to measure current in
this application?



** Yep.

Maybe try using a Hall effect sensor - no voltage drop involved at all
there.

Or just be a tad smarter bear and measure the current at a point in the
circuit that is NOT so damn sensitive to small voltage drops.



..... Phil




William Sommerwerck January 3rd 09 01:55 PM

Specification of current reading on multimeter
 
(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
current measurement?


Yes, at full scale. (You didn't say what the range was.)

The current ranges are probably implemented by switching the meter to its
200mV range and shunting the meter with a resistor that will produce a 200mV
drop for that current range.

So, for example, the 10A range uses a 20 milliohm shunt, while the 2mA range
uses a 100 ohm shunt. The actual drop varies linearly with the current, of
course.

How much this disturbs the circuit depends on the circuit's impedance. If
the charging light comes on when you're not using the meter, but doesn't
come on when you are, then, by definition, you're "disturbing" the circuit.

If you charge a lot of nicad and NiMH cells, get a MAHA (Powerex) MH-C9000
charger. Not cheap, but very convenient.



Eeyore January 3rd 09 03:12 PM

Specification of current reading on multimeter
 


nicola wrote:

I am in the UK. I have a £20 digital multimeter and would like
some advice. The meter is a Maplin model PG10B (order code GW18U)

http://www.maplin.co.uk/Module.aspx?ModuleNo=4402

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?


Yes.


(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
Current measurement?


Only at full scale reading. Adjust pro-rata.


(Q3) Isn't that figure of 200 mV rather high?


Pretty average.


I mean, if I use
the 2 mA or 20 mA scale in an electronics circuit powered by a 1.5
volt cell then a 200 mV drop in the circuit is very significant.


Yes.


My real need is to measure current while charging a AAA NiMH cell.

When I set my multimeter to measure DC Current and insert it in
the circuit, the charger's light fails to come on!

It's as if the prescence of the meter is disturbing the circuit
too much.

The voltage of my uncharged cell might typically be 1.1 volts and
the charger says it delivers up to about 120 mA.

(Q4) Is my multimeter simply too low-spec to measure current in
this application?


No, but you could measure the current further 'upstream' if possible to
avoid the problem.

Graham


William Sommerwerck January 3rd 09 03:17 PM

Specification of current reading on multimeter
 
If you charge a lot of nicad and NiMH cells, get a MAHA (Powerex)
MH-C9000
charger. Not cheap, but very convenient.


It is worthless


to you...

if it will not accept C cells, which are quite readily available now.


My electronic flashes and portable CD players, etc, do not accept C cells.


Pretty sad that I did not see any features that would make it worth
3 times what others go for either. No thanks.


You weren't looking. You might not need the features, but it has features
galore, including (but not limited to) the ability to select charging
current, to measure cell capacity, to "refresh" cells, etc.

Thomas Distributing currently (ar, ar) has it on sale for $40. I'm going to
get a second one.



Salmon Egg January 3rd 09 03:46 PM

Specification of current reading on multimeter
 
In article ,
nicola wrote:

I am in the UK. I have a £20 digital multimeter and would like
some advice. The meter is a Maplin model PG10B (order code GW18U)

http://www.maplin.co.uk/Module.aspx?ModuleNo=4402

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?


This probably means that that the 200 mV corresponds to the drop across
the meter required to give a full reading. If you do not need accurate
current measurement, increasing the current range setting will reduce
the voltage drop for the same current.

(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
Current measurement?


Find the impedance of the meter by dividing the 200 mV drop by the full
scale current. Use that to cvalculate the drop for measured current.
Subtract that off of the applied voltage. That is then what is left for
the rest of the circuit.

(Q3) Isn't that figure of 200 mV rather high? I mean, if I use
the 2 mA or 20 mA scale in an electronics circuit powered by a 1.5
volt cell then a 200 mV drop in the circuit is very significant.

Not necessarily. Higher resistance may be a way to increase sensitivity
for a low cost,
-----

My real need is to measure current while charging a AAA NiMH cell.

When I set my multimeter to measure DC Current and insert it in
the circuit, the charger's light fails to come on!

It's as if the prescence of the meter is disturbing the circuit
too much.

The voltage of my uncharged cell might typically be 1.1 volts and
the charger says it delivers up to about 120 mA.

(Q4) Is my multimeter simply too low-spec to measure current in
this application?


Could be.

nikk


Because electronic meters can vary all over the place, there can be all
kinds of peculiar nonlinear behavior that MAY kick in. That is not
likely, but possible.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!

William Sommerwerck January 3rd 09 04:14 PM

Specification of current reading on multimeter
 
"Archimedes' Lever" wrote in message
...
On Sat, 3 Jan 2009 07:17:07 -0800, "William Sommerwerck"
wrote:


Pretty sad that I did not see any features that would make it
worth 3 times what others go for either. No thanks.


You weren't looking. You might not need the features, but it has
features galore, including (but not limited to) the ability to select
charging current, to measure cell capacity, to "refresh" cells, etc.


Thomas Distributing currently (ar, ar) has it on sale for $40.
I'm going to get a second one.


My search found it at $37, but it still has problems. Most today auto
select the charge rate based on the battery being charged, and yes,
they can tell.


The MAHA lets you choose the capacity. You don't have to settle for what the
charger thinks is best.

A charger has no way of knowing a cell's capacity until it's measured it.
Most chargers have separate "tiered" contacts, so that AA cells are charged
at a higher rate than AAA. But that's the limit of their "knowledge".


NiCads and nmih batteries to not get "refresh" hits, and the cell
capacity is usually declared on the cell package or the cell itself.


Some people believe it's a good idea to periodically run down the cells.

Cells vary in capacity, despite their markings, and age differently, even
when those from the same production run. One of several I bought from Thomas
did not meet its spec'd capacity, even after several break-in cycles, and
MAHA replaced it.

The ability to measure capacity makes it possible to sort out your cells so
that every cell in a device "drops out" at about the same time. This reduces
the likelihood of cell reversal.


I did not see a display on it, so I do not know how your claim of
"measuring cell capacity" works.


It has an LCD that shows what's going on.

If _you_ don't need it, fine. But it's a terrific product. I'm glad I bought
mine.



Fred McKenzie January 3rd 09 07:47 PM

Specification of current reading on multimeter
 
In article ,
nicola wrote:

My real need is to measure current while charging a AAA NiMH cell.

When I set my multimeter to measure DC Current and insert it in
the circuit, the charger's light fails to come on!


Nikk-

As Bill mentioned, switching to a higher current range may lower the
meter's resistance to the point where the charger's light comes on.

Even though the charger's light fails to come on, do you read any
current at all on the meter? If not, you may have blown a fuse that
protects the meter's current ranges. If the fuse is only in the current
circuit, the meter may function normally for all other functions.

Fred

William Sommerwerck January 3rd 09 09:17 PM

Specification of current reading on multimeter
 
A charger has no way of knowing a cell's capacity until it's measured it.

Not true. It "measures it" as soon as it gets turned on (plugged in
with batteries installed). Itdetermines the battery type, and begins its
charging session based on its decision.


HOW? Explain.


Most chargers have separate "tiered" contacts, so that AA cells are
charged at a higher rate than AAA. But that's the limit of their

"knowledge".

Nope. The battery type, not form factor determine the charge rate.


You don't know what you're talking about.


The internal resistance on the two sizes is the same...


Yeah. Uh-huh.



William Sommerwerck January 3rd 09 09:18 PM

Specification of current reading on multimeter
 
The ability to measure capacity makes it possible to sort out your cells
so
that every cell in a device "drops out" at about the same time. This

reduces
the likelihood of cell reversal.


Sorry, but your charger does NOT send different voltages to each set of
cell contacts.


The thing energizes ALL the contacts at once, and the sensing takes
place on the bank as a group. As each battery is added, the only thing
that changes is the time period before the "charged" indicator lamp
lights.


Your answer has nothing whatever to do with my remark.



nicola January 3rd 09 09:47 PM

Specification of current reading on multimeter
 
On Sat 03 Jan 20:54, Archimedes' Lever
wrote

On Sat, 03 Jan 2009 14:47:01 -0500, Fred McKenzie
wrote:

In article ,
nicola wrote:

My real need is to measure current while charging a AAA NiMH
cell.

When I set my multimeter to measure DC Current and insert it
in the circuit, the charger's light fails to come on!


Nikk-

As Bill mentioned, switching to a higher current range may lower
the meter's resistance to the point where the charger's light
comes on.


Usually not True. Handheld meters current circuit usually uses
a single shunt. That is the cheap ones. It won't matter what
range he uses.

The more expensive, better made meters usually use two, and in
that case a different range will place a different value shunt
in the circuit.

I can't help thinking that he hooked it up wrong, because there
is nothing about such a small resistance that should stop the
charger's circuitry from sensing a battery in need of charge in
place.


Even though the charger's light fails to come on, do you read
any current at all on the meter? If not, you may have blown a
fuse that protects the meter's current ranges.


That is more likely. If it even has one. Again, the cheaper
meters do not, and the better ones do .

If the fuse is only in the current circuit, the meter may
function normally for all other functions.


Current metering that incorporates a fuse does so IN series with
the shunt, and it is the shunt, and other meter circuitry,
including the probe leads that the fuse 'protects' from
over-current conditions.

I can still remember a co-student back in '76, placing a meter
on the AC line with it set to current. It fried the Heathkit
totally. It was only $36, but back then that was a lot for a
student. Now, the fuse, which is nearly always incorporated in
all but the cheapest meters, would open, protecting the meter
guts.

Still, either shunt resistor should still be low enough in value
to have no effect on the charger's sense circuitry. I am
leaning toward there being a blown fuse. On the lowest setting,
and ammeter can even pick up "current" from local induction, so
even with the fuse blown, he *may* see some numbers flickering
across the display.



I will try again to get a reading and see if I did not do it
correctly the first time.

nicola January 3rd 09 09:52 PM

Specification of current reading on multimeter
 
On Sat 03 Jan 14:16, Stuart wrote

In article ,
nicola wrote:

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?


It is the volt drop across the meter at "full scale deflection".

If you measure 2mA on the 2mA range it will cause a 200mV drop.
If you measure 2mA on the 20mA range it will cause 20mV drop.


Oh! Now that isn't what I was expecting.

I read what others have posted about the meter being based arounf
a voltmeter which reads 200 mV at full scale.

I had inferred that the full scale deflection reading was
dependent on the range chosen.

So, for example, the full scale reading on a 20 mA range would be
20 mA. (On the 2mA range it would be 2 mA.) And I then had the
impression that when reading almost 20 mA on the 20 mA range, I
would get the 200 mV drop mentioned in the specs.

Is that understanding wrong?

nikk


nobody > January 3rd 09 10:09 PM

Specification of current reading on multimeter
 
Archimedes' Lever wrote:
On Sat, 3 Jan 2009 13:17:49 -0800, "William Sommerwerck"
wrote:

Nope. The battery type, not form factor determine the charge rate.

You don't know what you're talking about.



Bullcrap. I have both AAA, AA, and C size cells here, and the C size
cells have the same ampere hour rating that the AA batteries do. Guess
what that means to the charger, dingledorf?


Most of the supposed "C" rechargeables are nothing but an AA cell in a
plastic sleeve to bulk it out to C dimensions.

Ever wonder why they are so light?

William Sommerwerck January 3rd 09 10:34 PM

Specification of current reading on multimeter
 
I don't think Mr. Lever understands very much about batteries or their
recharging.

There's an old adage -- "An empty vessel makes the biggest noise."



Peter Bennett January 3rd 09 11:34 PM

Specification of current reading on multimeter
 
On Sat, 03 Jan 2009 21:52:52 GMT, nicola wrote:

On Sat 03 Jan 14:16, Stuart wrote

In article ,
nicola wrote:

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?


It is the volt drop across the meter at "full scale deflection".

If you measure 2mA on the 2mA range it will cause a 200mV drop.
If you measure 2mA on the 20mA range it will cause 20mV drop.


Oh! Now that isn't what I was expecting.

I read what others have posted about the meter being based arounf
a voltmeter which reads 200 mV at full scale.

I had inferred that the full scale deflection reading was
dependent on the range chosen.

So, for example, the full scale reading on a 20 mA range would be
20 mA. (On the 2mA range it would be 2 mA.) And I then had the
impression that when reading almost 20 mA on the 20 mA range, I
would get the 200 mV drop mentioned in the specs.

Is that understanding wrong?

nikk



No - it is correct.

The meter has a voltage drop of 200 mV at full scale - internally, it
is a 200 mV full scale meter.

If you measure a current of 2 mA on the 2 mA scale, the meter will
have a 200 mV voltage drop.

If you switch to the 20 mA scale, that 2 mA current will result in a
20 mV drop.

If you switch to the 200 mA scale, the 2 mA current will result in a 2
mV drop.

For any scale and current, the meter's voltage drop is:
(current/full_scale) * 200 mV


--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

krw[_5_] January 3rd 09 11:52 PM

Specification of current reading on multimeter
 
On Sat, 3 Jan 2009 14:34:45 -0800, "William Sommerwerck"
wrote:

I don't think Mr. Lever understands very much about batteries or their
recharging.


That's nothing new. DimBulb has a long history of demonstating zero
knowledge of everything. There is a long history behind his nickname,
"Always Wrong".

There's an old adage -- "An empty vessel makes the biggest noise."


DimBulb's head is *vacuum* empty.

William Sommerwerck January 4th 09 02:15 AM

Specification of current reading on multimeter
 
Why do you think that insulting me is going to get me upset or do your
reputation any good?



Eeyore January 4th 09 02:27 AM

Specification of current reading on multimeter
 


Archimedes' Lever wrote:

Bullcrap. I have both AAA, AA, and C size cells here, and the C size
cells have the same ampere hour rating that the AA batteries do. Guess
what that means to the charger, dingledorf?


Have you got NOTHING better in your life to do than aggravate people
needlessly ?

Playstation broken ?



krw[_5_] January 4th 09 05:27 AM

Specification of current reading on multimeter
 
On Sat, 03 Jan 2009 17:02:22 -0800, Archimedes' Lever
wrote:

On Sat, 03 Jan 2009 17:52:10 -0600, krw wrote:

On Sat, 3 Jan 2009 14:34:45 -0800, "William Sommerjerck"
wrote:

I don't think Mr. Lever understands very much about batteries or their
recharging.


That's nothing new. DimBulb has a long history of demonstating zero
knowledge of everything. There is a long history behind his nickname,
"Always Wrong".

There's an old adage -- "An empty vessel makes the biggest noise."


DimBulb's head is *vacuum* empty.



Said the retarded **** that spent NO time actually reading the thread,
and zero time refuting anything from a technical POV.


I've read the thread. You haven't fooled anyone here, DimBulb.

You suffer the same problem as SomeJerck does. Zero capacity to refute
with facts. Good job, KeithKiethTard.


I see no need to refute *everything* you say, even though it's always
wrong, AlwaysWrong . Others have done a good job here.

IanM[_4_] January 4th 09 12:11 PM

Specification of current reading on multimeter
 
Archimedes' Lever wrote:
On Sat, 03 Jan 2009 15:34:37 -0800, Peter Bennett
wrote:

On Sat, 03 Jan 2009 21:52:52 GMT, nicola wrote:

On Sat 03 Jan 14:16, Stuart wrote

In article ,
nicola wrote:

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?
It is the volt drop across the meter at "full scale deflection".

If you measure 2mA on the 2mA range it will cause a 200mV drop.
If you measure 2mA on the 20mA range it will cause 20mV drop.
Oh! Now that isn't what I was expecting.

I read what others have posted about the meter being based arounf
a voltmeter which reads 200 mV at full scale.

I had inferred that the full scale deflection reading was
dependent on the range chosen.

So, for example, the full scale reading on a 20 mA range would be
20 mA. (On the 2mA range it would be 2 mA.) And I then had the
impression that when reading almost 20 mA on the 20 mA range, I
would get the 200 mV drop mentioned in the specs.

Is that understanding wrong?

nikk


No - it is correct.

The meter has a voltage drop of 200 mV at full scale - internally, it
is a 200 mV full scale meter.

If you measure a current of 2 mA on the 2 mA scale, the meter will
have a 200 mV voltage drop.

If you switch to the 20 mA scale, that 2 mA current will result in a
20 mV drop.

If you switch to the 200 mA scale, the 2 mA current will result in a 2
mV drop.

For any scale and current, the meter's voltage drop is:
(current/full_scale) * 200 mV



Jeez dude. You can get a cheap $12 meter that has a much higher

^^^^^^
internal resistance at Harbor Freight or your local auto parts store.

Just get a better meter for the task.

^^^^^^
So Lever thinks higher resistance is better for measuring current!

ROTFLMAO

plonk

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL:

Phil Allison January 4th 09 01:18 PM

Specification of current reading on multimeter
 

Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long criminal history.

Do NOT TOLERATE SCUM like this vile puke ****ing up a news group.




...... Phil







Phil Allison January 4th 09 01:43 PM

Specification of current reading on multimeter
 

Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!





...... Phil




Phil Allison January 4th 09 01:53 PM

Specification of current reading on multimeter
 

Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!





...... Phil





Phil Allison January 4th 09 01:53 PM

Specification of current reading on multimeter
 


Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!






...... Phil





Phil Allison January 4th 09 01:54 PM

Specification of current reading on multimeter
 


Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!





...... Phil





IanM[_4_] January 4th 09 01:59 PM

Specification of current reading on multimeter
 
Hattori Hanzo wrote:
On Sun, 04 Jan 2009 12:11:13 +0000, IanM
wrote:

So Lever thinks higher resistance is better for measuring current!

ROTFLMAO



I was not referring to the shunt, you retarded twit.

-lol-

Thanks for revealing another nym. PLONK

If you have some more nyms handy you *could* try to explain how a higher
resistance meter movement or DVM module with the same FSD could read a
particular current at FSD with a lower resistance shunt, but then you'd
have to understand basic electrical theory. I'm not holding my breath.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL:

Dave Plowman (News) January 4th 09 02:05 PM

Specification of current reading on multimeter
 
In article ,
Phil Allison wrote:
Archimedes'= CRIMINAL PSYCHOPATH "



** Report this ****ING SCUMBAG to his ISP


NOW !!!!!!!!!!!!!!!!


Get the VILE PIG OFF usenet for ever.


The gutless POS anonymous ASSHOLE has a long criminal history.


Do NOT TOLERATE SCUM like this vile puke ****ing up a news group.


Oh the irony...

--
*Save the whale - I'll have it for my supper*

Dave Plowman London SW
To e-mail, change noise into sound.

William Sommerwerck January 4th 09 02:27 PM

Specification of current reading on multimeter
 
Oh the irony...

I hear pots and kettles banging loudly...



Lostgallifreyan January 4th 09 02:47 PM

Specification of current reading on multimeter
 
"Dave Plowman (News)" wrote in
:

In article ,
Phil Allison wrote:
Archimedes'= CRIMINAL PSYCHOPATH "



** Report this ****ING SCUMBAG to his ISP


NOW !!!!!!!!!!!!!!!!


Get the VILE PIG OFF usenet for ever.


The gutless POS anonymous ASSHOLE has a long criminal history.


Do NOT TOLERATE SCUM like this vile puke ****ing up a news group.


Oh the irony...


Yep, I'm plonking Phil too, the other guy's been plonked for months. I'm
tired of this, I don't care if someone knows useful facts if they can't focus
on applying them. As far as I'm concerned, this thread could have been done
days ago by someone dealing with what the OP wanted to DO, not how he assumed
it was to be done. I remember a tiny circuit with two ceramic caps and a 100K
resistor that would tap a phone line with negligible loading, and feed it
into a mic input ona cheap cassette recorder. Never mind the ringer or voice
signal voltage difference, it just kept the input current in safe limits and
let the inbult VGA take care of the sound. It didn't hum, or hiss. So long as
the line is correctly set up by whoever installed it, it works. Thing even
had a transistor based switch to detect the off-hook state to enable the
cassette recorder power switch. if the OP wants it I'll post, but I'm not
going to make any effort unasked for. Just writing anythign here, now, is
flamebait. Pathetic state of affairs, even before people start licking each
others areses and taking sides. Hopefully this crap stops before I feel the
need to block others who I normally take the time to listen to.

Jamie January 4th 09 03:59 PM

Specification of current reading on multimeter
 
Archimedes' Lever wrote:

On Sat, 3 Jan 2009 18:15:14 -0800, "William Sommerwerck"
wrote:


Why do you think that insulting me is going to get me upset or do your
reputation any good?


How can such an idiot actually think that he knows "what I think"?


No has to read your mind, when all you do is speak your mind.

http://webpages.charter.net/jamie_5"


Jamie January 4th 09 04:04 PM

Specification of current reading on multimeter
 
William Sommerwerck wrote:

Oh the irony...



I hear pots and kettles banging loudly...


"Shake, Rattle and Roll"
http://www.youtube.com/watch?v=20Feq_Nt3nM

http://webpages.charter.net/jamie_5"


Phil Allison January 5th 09 01:20 AM

Specification of current reading on multimeter
 

"Lostgallifreyan"


** This RETARDED ****HEAD needs kicking off usenet too.

Yep, I'm plonking Phil too, the other guy's been plonked for months. I'm
tired of this, I don't care if someone knows useful facts if they can't
focus
on applying them. As far as I'm concerned, this thread could have been
done
days ago by someone dealing with what the OP wanted to DO, not how he
assumed
it was to be done. I remember a tiny circuit with two ceramic caps and a
100K
resistor that would tap a phone line with negligible loading,



** ROTFLMAO !!!

Read the damn heading - you are in the WRONG THREAD

****WIT TROLL !!!!




...... Phil



Don Kelly[_2_] January 5th 09 01:44 AM

Specification of current reading on multimeter
 
Phil Allison wrote:
Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!





..... Phil





plonk

--
Don Kelly

remove X to reply

ian field[_2_] January 5th 09 07:11 PM

Specification of current reading on multimeter
 

"nicola" wrote in message
...
I am in the UK. I have a £20 digital multimeter and would like
some advice. The meter is a Maplin model PG10B (order code GW18U)

http://www.maplin.co.uk/Module.aspx?ModuleNo=4402

(Q1) Under "DC CURRENT" my user guide says, "voltage drop: 200
mV". Is this the disturbance in a circuit when measuring DC
current?

(Q2) If so, then does that 200 mV figure mean that the potential
difference for the rest of the circuit will be reduced by 200 mV
once I have interrupted the circuit and inserted my meter for DC
Current measurement?

(Q3) Isn't that figure of 200 mV rather high? I mean, if I use
the 2 mA or 20 mA scale in an electronics circuit powered by a 1.5
volt cell then a 200 mV drop in the circuit is very significant.


One way round this is to use a stable adjustable PSU and adjust for the
required voltage *after* the current meter. If your circuit draws large
pulses, pad the supply rails with a hefty electrolytic.



ian field[_2_] January 5th 09 07:22 PM

Specification of current reading on multimeter
 

"Capt. Cave Man" wrote in message
...
On Mon, 5 Jan 2009 00:43:10 +1100, "Phil Allison"
wrote:


Archimedes'= CRIMINAL PSYCHOPATH "


** Report this ****ING SCUMBAG to his ISP

NOW !!!!!!!!!!!!!!!!

Get the VILE PIG OFF usenet for ever.

The gutless POS anonymous ASSHOLE has a long CRIMINAL history.


Do NOT TOLERATE VILE SCUM like this puke

****ing up YOUR news group !!!!





..... Phil


What's wrong, PhilTard? Don't like it when someone sides with someone
your retarded ass disagrees with?

TOO BAD.

Anything to say that has any modicum of intelligence?


Philthy is between the point where he stopped taking his tablets and the
point where they hold him down and give him an injection.



ancient-time-traveler January 5th 09 10:03 PM

Specification of current reading on multimeter
 
On Jan 4, 9:27*am, "William Sommerwerck"
wrote:
Oh the irony...


I hear pots and kettles banging loudly...


11,000 microamps

ian field[_2_] January 5th 09 10:19 PM

Specification of current reading on multimeter
 

"nicola" wrote in message
...
I am in the UK. I have a £20 digital multimeter


Ask in store to be put on the mailing list and wait for a special offer
better spec meter to be discounted.

Better yet look elsewhere for a better quality instrument and grin & bear
the price, the last meter I bought from Maplin a couple of years ago worked
ok for a while then some of the segments in the display failed, this turned
out to be migrating flux on the LCD contact pads so I was able to fix it
reasonably easily, but this seems to be a bit of a trend with stuff I've
bought from Maplin.



Michael A. Terrell January 5th 09 10:26 PM

Specification of current reading on multimeter
 

ian field wrote:

Philthy is between the point where he stopped taking his tablets and the
point where they hold him down and give him an injection.



They need to try Cyanide this time.


--
http://improve-usenet.org/index.html

aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.

If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm


There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.

ian field[_2_] January 6th 09 05:16 PM

Specification of current reading on multimeter
 

"Michael A. Terrell" wrote in message
m...

ian field wrote:

Philthy is between the point where he stopped taking his tablets and the
point where they hold him down and give him an injection.



They need to try Cyanide this time.


Cardiac injection of Harpic.



Michael A. Terrell January 6th 09 10:12 PM

Specification of current reading on multimeter
 

ian field wrote:

"Michael A. Terrell" wrote in message
m...

ian field wrote:

Philthy is between the point where he stopped taking his tablets and the
point where they hold him down and give him an injection.



They need to try Cyanide this time.


Cardiac injection of Harpic.



Or manual insertion of large quantities of molded lead pellets.


--
http://improve-usenet.org/index.html

aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.

If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm


There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.


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