Residual current measurement

[Noodnik]

Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good first
step, but I wonder whether geometry or interwinding screening needs to be
consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from contacting
a qualified, licenced electrician?

 

[Noodnik]

"Noodnik" <Noodnik@NotHere.com> wrote in message
news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...

Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from
contacting a qualified, licenced electrician?
Nobrainer in fact. CT on the earth lead of the appliance.

 

[Phil Allison]

"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.



..... Phil

 

[Grant]

On Sun, 5 Sep 2010 09:10:11 +0800, "Noodnik" <Noodnik@NotHere.com> wrote:

Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good first
step, but I wonder whether geometry or interwinding screening needs to be
consdered to achieve the sensitivity required.

You can buy an extension lead with RCD built in, try it on appliances you
suspect.

What's new in, on the house, to cause a problem?

Grant.

 

[bristan]

"Noodnik" <Noodnik@NotHere.com> wrote in message
news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...

Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from
contacting a qualified, licenced electrician?
A fairly common problem in houses a few years old according to the

electrician who fixed mine.
A clothes drier was tripping out the device when we switched it on.
He fitted a second one to the board and divided up the circuits accordingly.
No further problems

 

[John G]

Noodnik formulated the question :

"Noodnik" <Noodnik@NotHere.com> wrote in message
news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...
Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from contacting
a qualified, licenced electrician?
Nobrainer in fact. CT on the earth lead of the appliance.

The fault current may not flow thru the earth lead.
It may flow from the frame of someting not earthed thru YOU.

Double insulated devices without an earth lead can still trip an RCD if
they are faulty.

--
JohnG

 

[kreed]

On Sep 5, 11:17 am, "Noodnik" <Nood...@NotHere.com> wrote:

"Noodnik" <Nood...@NotHere.com> wrote in message

news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...> Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done.  Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from
contacting a qualified, licenced electrician?

Nobrainer in fact. CT on the earth lead of the appliance.

Would need to measure the current on the active and neutral to the
appliance, at the same time, and calculate the difference if any.
That difference will be your leakage & that is how your ELCB works.


-Buy a "Megger" tester and test each appliance in your premises with
it. This will also help reveal any suspect device that might be
breaking down, but not enough yet to trip an ELCB.

If the ELCB is tripping because of several appliances leaking a
little, and the cumulative leakage current being enough to trip the
ELCB, this is about the only way you are going to find it.


-Buy a portable ELCB, or roll your own by building an ELCB into a
suitable enclosure with a plug and socket on it and plug it in series
with each appliance in turn until you get it tripping.
You might have to build your own anyway if you are want to test or
protect portable devices that are 15A or over, or are 3 phase as
portable consumer ELCB's are typically 10A single phase.
When it trips, than you have found the culprit device.

 

[Jasen Betts]

On 2010-09-05, Phil Allison <phil_a@tpg.com.au> wrote:

"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)

--
¡spuɐɥ ou 'ɐꟽ ʞooꞀ

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[F Murtz]

kreed wrote:

On Sep 5, 11:17 am, "Noodnik"<Nood...@NotHere.com> wrote:
"Noodnik"<Nood...@NotHere.com> wrote in message

news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...> Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done. Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from
contacting a qualified, licenced electrician?

Nobrainer in fact. CT on the earth lead of the appliance.


Would need to measure the current on the active and neutral to the
appliance, at the same time, and calculate the difference if any.
That difference will be your leakage& that is how your ELCB works.


-Buy a "Megger" tester and test each appliance in your premises with
it. This will also help reveal any suspect device that might be
breaking down, but not enough yet to trip an ELCB.

Which will promptly destroy many electrical devices.

If the ELCB is tripping because of several appliances leaking a
little, and the cumulative leakage current being enough to trip the
ELCB, this is about the only way you are going to find it.


-Buy a portable ELCB, or roll your own by building an ELCB into a
suitable enclosure with a plug and socket on it and plug it in series
with each appliance in turn until you get it tripping.
You might have to build your own anyway if you are want to test or
protect portable devices that are 15A or over, or are 3 phase as
portable consumer ELCB's are typically 10A single phase.
When it trips, than you have found the culprit device.

 

[Phil Allison]

"Jasen the Troll Fucks Dead Sheep "

"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)

** Far stupider that Noodledick's insane crapology.




..... Phil

 

[Phil Allison]

"kreed"

Would need to measure the current on the active and neutral to the
appliance, at the same time, and calculate the difference if any.
That difference will be your leakage & that is how your ELCB works.


** Totally STUPID crap.



-Buy a "Megger" tester and test each appliance in your premises with
it. This will also help reveal any suspect device that might be
breaking down, but not enough yet to trip an ELCB.

** Totally STUPID crap.



If the ELCB is tripping because of several appliances leaking a
little, and the cumulative leakage current being enough to trip the
ELCB, this is about the only way you are going to find it.

** Totally STUPID crap.

 

[kreed]

On Sep 5, 10:06 pm, F Murtz <hagg...@hotmail.com> wrote:

kreed wrote:
On Sep 5, 11:17 am, "Noodnik"<Nood...@NotHere.com>  wrote:
"Noodnik"<Nood...@NotHere.com>  wrote in message

news:fuCdnSVIb85ocB_RnZ2dnUVZ8n6dnZ2d@westnet.com.au...>  Hi, House is going out on residual current occasionally, all the obvious,
easy checks have been done.  Has anyone come across a device that measures
residual current of appliances, or built one? A CT is obviously a good
first step, but I wonder whether geometry or interwinding screening needs
to be consdered to achieve the sensitivity required.

Any other practical suggestions to sort this problem, aside from
contacting a qualified, licenced electrician?

Nobrainer in fact. CT on the earth lead of the appliance.

Would need to measure the current on the active and neutral to the
appliance, at the same time, and calculate the difference if any.
That difference will be your leakage&  that is how your ELCB works.

-Buy a "Megger" tester and test each appliance in your premises with
it. This will also help reveal any suspect device that might be
breaking down, but not enough yet to trip an ELCB.

Which will promptly destroy many electrical devices.

I would assume that it is going to be used properly ??

If the ELCB is tripping because of several appliances leaking a
little, and the cumulative leakage current being enough to trip the
ELCB, this is about the only way you are going to find it.

-Buy a portable ELCB, or roll your own by building an ELCB into a
suitable enclosure with a plug and socket on it and plug it in series
with each appliance in turn until you get it tripping.
You might have to build your own anyway if you are want to test or
protect portable devices that are 15A or over, or are 3 phase as
portable consumer ELCB's are typically 10A single phase.
When it trips, than you have found the culprit device.

 

[Grant]

On 5 Sep 2010 11:10:19 GMT, Jasen Betts <jasen@xnet.co.nz> wrote:

On 2010-09-05, Phil Allison <phil_a@tpg.com.au> wrote:

"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)

I had a problem trying to sort out why a newish switching supply trip
RCD, yet it worked fine in the shop. So far all I can guess is that it's
due to poor earthing, I'm in rear unit with long earth run, and my friend
hand problems up the back shed, also a long earth run.

More here for the curious: http://grrr.id.au/ps-earth-current/

I could stop the RCD from triggering with some extra inline filtering,
but there's not a lot one can do for conducted interference down the
earth lead? In the end the PS owner decided not to do anything, unless
it tripped on customer's site (Ouch!) embarrassing.

Grant.

 

[who where]

On Mon, 06 Sep 2010 08:16:32 +1000, Grant <omg@grrr.id.au> wrote:

I had a problem trying to sort out why a newish switching supply trip
RCD, yet it worked fine in the shop. So far all I can guess is that it's
due to poor earthing, I'm in rear unit with long earth run, and my friend
hand problems up the back shed, also a long earth run.

More here for the curious: http://grrr.id.au/ps-earth-current/

I could stop the RCD from triggering with some extra inline filtering,
but there's not a lot one can do for conducted interference down the
earth lead? In the end the PS owner decided not to do anything, unless
it tripped on customer's site (Ouch!) embarrassing.

I had a dedicated ELCB dual GPO fitted to a workbench where radio
equipment is serviced (this is *years* before RCD's became
law/popular). It used to trip when a transmitter connected to a large
DC PSU was fired up. Putting a large ferrite toroid over the DC lead
stopped the RF getting back into the ELCB core. Clipsal confirmed
that their core balance amp was conducted-RF-sensitive.

 

[Grant]

On Mon, 06 Sep 2010 08:46:04 +0800, who where <noone@home.net> wrote:

On Mon, 06 Sep 2010 08:16:32 +1000, Grant <omg@grrr.id.au> wrote:

I had a problem trying to sort out why a newish switching supply trip
RCD, yet it worked fine in the shop. So far all I can guess is that it's
due to poor earthing, I'm in rear unit with long earth run, and my friend
hand problems up the back shed, also a long earth run.

More here for the curious: http://grrr.id.au/ps-earth-current/

I could stop the RCD from triggering with some extra inline filtering,
but there's not a lot one can do for conducted interference down the
earth lead? In the end the PS owner decided not to do anything, unless
it tripped on customer's site (Ouch!) embarrassing.

I had a dedicated ELCB dual GPO fitted to a workbench where radio
equipment is serviced (this is *years* before RCD's became
law/popular). It used to trip when a transmitter connected to a large
DC PSU was fired up. Putting a large ferrite toroid over the DC lead
stopped the RF getting back into the ELCB core. Clipsal confirmed
that their core balance amp was conducted-RF-sensitive.

Wouldn't surprise me, close to 10mA of 28kHz triggered the thing

But I needed lots more than ferrite over the wire, a few turns of the
three leads through a pair of large toroids, too fugly to contemplate
as an add-on.

Grant.

 

[Noodnik]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:8ehkfnFtinU1@mid.individual.net...

"Jasen the Troll Fucks Dead Sheep "


"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)


** Far stupider that Noodledick's insane crapology.




.... Phil

Phil, You should have chosen your dramatic reentrance in a way that hides

your knowledge boundaries better. How much do you actually know about CTs?
They're universally used on earth legs higher up in the distribution system
for fault detection, and can be constructed so they pose no interruption
whatosever to the earth path. For checking the leakage on an earthed
appliance such as a fridge they're a totally safe, practical solution.

The dual live/neutral winding approach used with RCDs is there simply
because there's no single point of access to the common earth conductor for
the circuits to be monitored, and also to capture 2-wire equipment.

 

[Noodnik]

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:8ehkfnFtinU1@mid.individual.net...

"Jasen the Troll Fucks Dead Sheep "


"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)


** Far stupider that Noodledick's insane crapology.




.... Phil

Phil, You should have saved your dramatic reentry for something that hides

your knowledge boundaries better. How much do you actually know about CTs?
They're used widely in earth legs higher up the supply network for fault
detection, and can be constructed in a way that avoids any interruption
whatsoever in the earth path. For temporary measuring of earth leakage on an
earthed domestic appliance such as a fridge, they're an ideal, and totally
safe solution.

 

[John G]

Noodnik explained on 6/09/2010 :

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:8ehkfnFtinU1@mid.individual.net...

"Jasen the Troll Fucks Dead Sheep "


"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)


** Far stupider that Noodledick's insane crapology.




.... Phil

Phil, You should have saved your dramatic reentry for something that hides
your knowledge boundaries better. How much do you actually know about CTs?
They're used widely in earth legs higher up the supply network for fault
detection, and can be constructed in a way that avoids any interruption
whatsoever in the earth path. For temporary measuring of earth leakage on an
earthed domestic appliance such as a fridge, they're an ideal, and totally
safe solution.

You do not understand Earth Leakage.

There is no need for an EARTH conductor and measuring just THAT current
is not a solution.

Earth Leakage or actually Imbalance of current between the active and
the neautral can follow many paths.
Hence to measure it you need a pair of CTs and a very good resolution
method of reading the difference between the 2.
Simple solution is a portable RCD which is carefully designed to do
JUST this job.

--
JohnG

 

[Phil Allison]

"Noodle dick is Insane"

"Phil Allison"

"Jasen the Troll Fucks Dead Sheep "


"Noodle dick"

Nobrainer in fact. CT on the earth lead of the appliance.

** Someone with no brains would do that.

See guys Phil is alive and well, just noone had posted a stupid and
dangerous enough suggestion to provoke him.

(CT on the phase and neutral wires is the correct answer)


** Far stupider that Noodledick's insane crapology.


Phil,

** Go get stuffed you utterly stupid pig.



..... Phil

 

[atec77]

On 7/09/2010 12:15 AM, Phil Allison wrote:
still sucking and taking one in the arse philthy ?



no don't tell us really it's rhetorical
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