Woke up this morning to find the RCD in the split load CU had tripped.
Turned out to be something on the 1st floor ring. With that MCB off, no
problems. Put it to on, and the RCD tripped again.

Unplugged everything on it. Fine. Slowly re-instate things and haven't
found the problem one(s) yet. I suspect it is a current sensing 4 way
outlet in the spare room which feeds the AC system there.

It's only when you do this sort of thing you realise just how much stuff
you have. ;-)

Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

--
*Experience is something you don't get until just after you need it.*

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

On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

In article ,
wrote:
On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

Thanks Owain. Did just wonder if there was a device you plugged the
appliance into which then gave a direct read out of leakage current.

--
*I was once a millionaire but my mom gave away my baseball cards

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

But hang on a moment, many devices have mains filters that as a transient
would fail those tests, as they have capacitors in them which have to
presumably charge and discharge on each cycle of the mains.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

Brian Gaff (Sofa 2) wrote:

But hang on a moment, many devices have mains filters that as a transient
would fail those tests, as they have capacitors in them which have to
presumably charge and discharge on each cycle of the mains.
Brian

This is best analysed as an AC current (sic) rather than as transients,
and must meet the limits set. Hence filter capacitors to earth have to
have a lower value than capacitors across live and neutral, which latter
don't contribute to earth leakage.

--

Roger Hayter

Hmm, well, that lets the ones I used to build be non starters then. grin.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Roger Hayter" wrote in message
...
Brian Gaff (Sofa 2) wrote:

But hang on a moment, many devices have mains filters that as a
transient
would fail those tests, as they have capacitors in them which have to
presumably charge and discharge on each cycle of the mains.
Brian

This is best analysed as an AC current (sic) rather than as transients,
and must meet the limits set. Hence filter capacitors to earth have to
have a lower value than capacitors across live and neutral, which latter
don't contribute to earth leakage.

--

Roger Hayter

On 23/11/2019 13:37, Dave Plowman (News) wrote:
In article ,
wrote:
On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

Thanks Owain. Did just wonder if there was a device you plugged the
appliance into which then gave a direct read out of leakage current.

You can get high sensitivity clamp meters that will (with the aid of a
short extension lead with the individual insulated wires made
accessible) allow direct measurement of leakage if its directly to the
circuit earth (obviously it won't see leakage via a parallel path to earth)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article , Dave Plowman (News)
scribeth thus
In article ,
wrote:
On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

Thanks Owain. Did just wonder if there was a device you plugged the
appliance into which then gave a direct read out of leakage current.


Don't overlook that odd Neutral to Earth leakage short which can cause
quite some fun and games as the load increases in the system!..
--
Tony Sayer


Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

On Saturday, 23 November 2019 13:37:32 UTC, Dave Plowman (News) wrote:
In article ,
wrote:
On Saturday, 23 November 2019 11:06:56 UTC, Dave Plowman (News) wrote:
Wondered if there was some form of 'leakage' tester I could buy or make?
To find out the actual fault current in each and every thing which is
plugged in to it? And what is acceptable - as I realise some things will
have some anyway.

Any megger / insulation tester and test between (L+N) and E.

15 mA may trip a 30 mA RCD and that's 16 kOhm at 240 volts.

Permitted leakage for PAT:

Class Type Max Leakage Current
1 IT, Movable, Stationary, & Fixed 3.5mA
1 Heating & Cooking 0.75mA per kW*
2 All Types 0.25mA
* to a maximum of 5mA

https://www.pat-testing-training.net...ge-current.php

Owain

Thanks Owain. Did just wonder if there was a device you plugged the
appliance into which then gave a direct read out of leakage current.

PAT tester or megger. Or you can do it at mains voltage with just a meter & protecting resistor. Or use a microwave turntable motor as a 0-1000v supply.

But a multimeter, they pick up a useful percentage of faults.


NT