John Towill wrote:

A word of warning, if you are using an electrical appliance on a long lead
plug the RCD into the end of the extension lead. If there is a long lead
between you and the LCD the finite time taken for it to react could give you
little or no protection.

What a load of rubbish!

The RCD will trip just as quickly whichever end of the lead it is at
(within a few nanoseconds anyway, immaterial to your safety).

What this posting *may* be referring to is the CPC (earth) conductor
resistance which *does* affect the speed at which an MCB (overload
protection device) will trip. However you'll never have an MCB at the
'user' end of the cable, it's not practical. The point of using an
RCD in this situation is that it overcomes the possible problem with
the slowness of the MCB (and offers other protection as well).

--
Chris Green )

Rick McGreal wrote:
"Dave Liquorice" wrote in
ill.network:

On Sun, 18 May 2003 15:06:57 +0100, John Towill wrote:

A word of warning, if you are using an electrical appliance on a
long lead plug the RCD into the end of the extension lead.

ARGH! NO!!

This is just plain wrong and dangerous in that you *think* you have
RCD protection but you haven't. If you damage that extension cable you
have *no* RCD protection. See you at St Peters Gates...

Don't breakers go in the wall socket and the extension goes into that?

Thats what I have been doing with my mower and stereo....

If you have no other RCD protection then that's a way to do it but if
you have a recent electrical installation it may well be that all your
sockets (or at least the downstairs ones) are RCD protected anyway so
you're wasting your time (and money!) adding a plug in one as well.

--
Chris Green )

Rick McGreal wrote:
"Dave Liquorice" wrote in
ill.network:

On Sun, 18 May 2003 15:06:57 +0100, John Towill wrote:

A word of warning, if you are using an electrical appliance on a
long lead plug the RCD into the end of the extension lead.

ARGH! NO!!

This is just plain wrong and dangerous in that you *think* you have
RCD protection but you haven't. If you damage that extension cable you
have *no* RCD protection. See you at St Peters Gates...

Don't breakers go in the wall socket and the extension goes into that?

Thats what I have been doing with my mower and stereo....

If you have no other RCD protection then that's a way to do it but if
you have a recent electrical installation it may well be that all your
sockets (or at least the downstairs ones) are RCD protected anyway so
you're wasting your time (and money!) adding a plug in one as well.

--
Chris Green )

Rick McGreal wrote:
"Dave Liquorice" wrote in
ill.network:

On Sun, 18 May 2003 15:06:57 +0100, John Towill wrote:

A word of warning, if you are using an electrical appliance on a
long lead plug the RCD into the end of the extension lead.

ARGH! NO!!

This is just plain wrong and dangerous in that you *think* you have
RCD protection but you haven't. If you damage that extension cable you
have *no* RCD protection. See you at St Peters Gates...

Don't breakers go in the wall socket and the extension goes into that?

Thats what I have been doing with my mower and stereo....

If you have no other RCD protection then that's a way to do it but if
you have a recent electrical installation it may well be that all your
sockets (or at least the downstairs ones) are RCD protected anyway so
you're wasting your time (and money!) adding a plug in one as well.

--
Chris Green )

Dave Liquorice wrote:
On Sun, 18 May 2003 20:35:05 +0100, DDEckerslyke wrote:

I knew this wasn't going to be simple. OK I've had a look on the
fuse box and what seem to be relevant are the following:

'ELCB automatically switches off when an earth fault occurs'
'Residual Current Operated Circuit Breaker'

So you do have an RCD in the fuse box, good. Now what circuits is it
protecting? The labling should tell you which circuits are RCD
protected and which aren't (if any). If the circuit (or ring) that you
use for external appliances is protected by this RCD then you are
protected. Use the test button every so often, 6 months to a year is
fine.

'404ELHNC'

Type/model number.

'I subscript n = 80A'

Capable of switching 80A.

'I with three subscripts that look like O, delta, n = 30mA'

Trips at a nominal 30mA of leakage.

Will we need an RCD?

Is this device at one end or somewhere in the middle with a bigger
switch at (normally) the right hand end?

If it's protecting the whole house it's really the wrong type, a whole
house RCD should be a 100mA time delayed device and other circuits
(such as those feeding garages, used outside etc) should have their
own 30mA non delayed devices.

Yes, but *many* older installations are protected by a single 30mA
device for the whole installation. Since this is labelled as an
"ELCB" then it seems likely to me that is is protecting the whole
isnatllation.


The big snag with a whole house RCD is if it trips the lights go out,
not nice if your up a ladder and just, stupidly, accidentally shorted
something or picked up the mains... or your doing something and some
one else causes it to trip.

Very true, but it's quite an expensive job to re-do everything to
split things up. (Well, it's not *that* expensive in materials but
unless you D-I-Y it can be expensive to have it done for you)

--
Chris Green )

Dave Liquorice wrote:
On Sun, 18 May 2003 20:35:05 +0100, DDEckerslyke wrote:

I knew this wasn't going to be simple. OK I've had a look on the
fuse box and what seem to be relevant are the following:

'ELCB automatically switches off when an earth fault occurs'
'Residual Current Operated Circuit Breaker'

So you do have an RCD in the fuse box, good. Now what circuits is it
protecting? The labling should tell you which circuits are RCD
protected and which aren't (if any). If the circuit (or ring) that you
use for external appliances is protected by this RCD then you are
protected. Use the test button every so often, 6 months to a year is
fine.

'404ELHNC'

Type/model number.

'I subscript n = 80A'

Capable of switching 80A.

'I with three subscripts that look like O, delta, n = 30mA'

Trips at a nominal 30mA of leakage.

Will we need an RCD?

Is this device at one end or somewhere in the middle with a bigger
switch at (normally) the right hand end?

If it's protecting the whole house it's really the wrong type, a whole
house RCD should be a 100mA time delayed device and other circuits
(such as those feeding garages, used outside etc) should have their
own 30mA non delayed devices.

Yes, but *many* older installations are protected by a single 30mA
device for the whole installation. Since this is labelled as an
"ELCB" then it seems likely to me that is is protecting the whole
isnatllation.


The big snag with a whole house RCD is if it trips the lights go out,
not nice if your up a ladder and just, stupidly, accidentally shorted
something or picked up the mains... or your doing something and some
one else causes it to trip.

Very true, but it's quite an expensive job to re-do everything to
split things up. (Well, it's not *that* expensive in materials but
unless you D-I-Y it can be expensive to have it done for you)

--
Chris Green )

Dave Liquorice wrote:
On Sun, 18 May 2003 20:35:05 +0100, DDEckerslyke wrote:

I knew this wasn't going to be simple. OK I've had a look on the
fuse box and what seem to be relevant are the following:

'ELCB automatically switches off when an earth fault occurs'
'Residual Current Operated Circuit Breaker'

So you do have an RCD in the fuse box, good. Now what circuits is it
protecting? The labling should tell you which circuits are RCD
protected and which aren't (if any). If the circuit (or ring) that you
use for external appliances is protected by this RCD then you are
protected. Use the test button every so often, 6 months to a year is
fine.

'404ELHNC'

Type/model number.

'I subscript n = 80A'

Capable of switching 80A.

'I with three subscripts that look like O, delta, n = 30mA'

Trips at a nominal 30mA of leakage.

Will we need an RCD?

Is this device at one end or somewhere in the middle with a bigger
switch at (normally) the right hand end?

If it's protecting the whole house it's really the wrong type, a whole
house RCD should be a 100mA time delayed device and other circuits
(such as those feeding garages, used outside etc) should have their
own 30mA non delayed devices.

Yes, but *many* older installations are protected by a single 30mA
device for the whole installation. Since this is labelled as an
"ELCB" then it seems likely to me that is is protecting the whole
isnatllation.


The big snag with a whole house RCD is if it trips the lights go out,
not nice if your up a ladder and just, stupidly, accidentally shorted
something or picked up the mains... or your doing something and some
one else causes it to trip.

Very true, but it's quite an expensive job to re-do everything to
split things up. (Well, it's not *that* expensive in materials but
unless you D-I-Y it can be expensive to have it done for you)

--
Chris Green )

Jon Rouse wrote:
In article , DDEckerslyke
writes

There seem to be different types of RCD - which is best for a lawnmower?
Where do you buy them from? (not necessarily on line)
How much do they cost?

I've had a qualcast one for years, and its been very good - I've used it
for all sorts of things. Unfortunately although it is rated at 3Kva I've
just melted it by running an immersion heater through it. RIP.

Why on earth would you wan't to run an immersion heater on an RCD
protected circuit!? It really doesn't do anything for you (safety
wise) for an appliance like this. Not to mention that an immersion
heater shouldn't really be connected via a plug anyway (it sounds like
this one is).

--
Chris Green )

Jon Rouse wrote:
In article , DDEckerslyke
writes

There seem to be different types of RCD - which is best for a lawnmower?
Where do you buy them from? (not necessarily on line)
How much do they cost?

I've had a qualcast one for years, and its been very good - I've used it
for all sorts of things. Unfortunately although it is rated at 3Kva I've
just melted it by running an immersion heater through it. RIP.

Why on earth would you wan't to run an immersion heater on an RCD
protected circuit!? It really doesn't do anything for you (safety
wise) for an appliance like this. Not to mention that an immersion
heater shouldn't really be connected via a plug anyway (it sounds like
this one is).

--
Chris Green )

Jon Rouse wrote:
In article , DDEckerslyke
writes

There seem to be different types of RCD - which is best for a lawnmower?
Where do you buy them from? (not necessarily on line)
How much do they cost?

I've had a qualcast one for years, and its been very good - I've used it
for all sorts of things. Unfortunately although it is rated at 3Kva I've
just melted it by running an immersion heater through it. RIP.

Why on earth would you wan't to run an immersion heater on an RCD
protected circuit!? It really doesn't do anything for you (safety
wise) for an appliance like this. Not to mention that an immersion
heater shouldn't really be connected via a plug anyway (it sounds like
this one is).

--
Chris Green )

John Towill wrote:

A word of warning, if you are using an electrical appliance on a long lead
plug the RCD into the end of the extension lead. If there is a long lead
between you and the LCD the finite time taken for it to react could give you
little or no protection.

What a load of rubbish!

The RCD will trip just as quickly whichever end of the lead it is at
(within a few nanoseconds anyway, immaterial to your safety).

What this posting *may* be referring to is the CPC (earth) conductor
resistance which *does* affect the speed at which an MCB (overload
protection device) will trip. However you'll never have an MCB at the
'user' end of the cable, it's not practical. The point of using an
RCD in this situation is that it overcomes the possible problem with
the slowness of the MCB (and offers other protection as well).

--
Chris Green )

Rick McGreal wrote:
"Dave Liquorice" wrote in
ill.network:

On Sun, 18 May 2003 15:06:57 +0100, John Towill wrote:

A word of warning, if you are using an electrical appliance on a
long lead plug the RCD into the end of the extension lead.

ARGH! NO!!

This is just plain wrong and dangerous in that you *think* you have
RCD protection but you haven't. If you damage that extension cable you
have *no* RCD protection. See you at St Peters Gates...

Don't breakers go in the wall socket and the extension goes into that?

Thats what I have been doing with my mower and stereo....

If you have no other RCD protection then that's a way to do it but if
you have a recent electrical installation it may well be that all your
sockets (or at least the downstairs ones) are RCD protected anyway so
you're wasting your time (and money!) adding a plug in one as well.

--
Chris Green )

Dave Liquorice wrote:
On Sun, 18 May 2003 20:35:05 +0100, DDEckerslyke wrote:

I knew this wasn't going to be simple. OK I've had a look on the
fuse box and what seem to be relevant are the following:

'ELCB automatically switches off when an earth fault occurs'
'Residual Current Operated Circuit Breaker'

So you do have an RCD in the fuse box, good. Now what circuits is it
protecting? The labling should tell you which circuits are RCD
protected and which aren't (if any). If the circuit (or ring) that you
use for external appliances is protected by this RCD then you are
protected. Use the test button every so often, 6 months to a year is
fine.

'404ELHNC'

Type/model number.

'I subscript n = 80A'

Capable of switching 80A.

'I with three subscripts that look like O, delta, n = 30mA'

Trips at a nominal 30mA of leakage.

Will we need an RCD?

Is this device at one end or somewhere in the middle with a bigger
switch at (normally) the right hand end?

If it's protecting the whole house it's really the wrong type, a whole
house RCD should be a 100mA time delayed device and other circuits
(such as those feeding garages, used outside etc) should have their
own 30mA non delayed devices.

Yes, but *many* older installations are protected by a single 30mA
device for the whole installation. Since this is labelled as an
"ELCB" then it seems likely to me that is is protecting the whole
isnatllation.


The big snag with a whole house RCD is if it trips the lights go out,
not nice if your up a ladder and just, stupidly, accidentally shorted
something or picked up the mains... or your doing something and some
one else causes it to trip.

Very true, but it's quite an expensive job to re-do everything to
split things up. (Well, it's not *that* expensive in materials but
unless you D-I-Y it can be expensive to have it done for you)

--
Chris Green )

Jon Rouse wrote:
In article , DDEckerslyke
writes

There seem to be different types of RCD - which is best for a lawnmower?
Where do you buy them from? (not necessarily on line)
How much do they cost?

I've had a qualcast one for years, and its been very good - I've used it
for all sorts of things. Unfortunately although it is rated at 3Kva I've
just melted it by running an immersion heater through it. RIP.

Why on earth would you wan't to run an immersion heater on an RCD
protected circuit!? It really doesn't do anything for you (safety
wise) for an appliance like this. Not to mention that an immersion
heater shouldn't really be connected via a plug anyway (it sounds like
this one is).

--
Chris Green )

John Towill wrote:

A word of warning, if you are using an electrical appliance on a long lead
plug the RCD into the end of the extension lead. If there is a long lead
between you and the LCD the finite time taken for it to react could give you
little or no protection.

What a load of rubbish!

The RCD will trip just as quickly whichever end of the lead it is at
(within a few nanoseconds anyway, immaterial to your safety).

What this posting *may* be referring to is the CPC (earth) conductor
resistance which *does* affect the speed at which an MCB (overload
protection device) will trip. However you'll never have an MCB at the
'user' end of the cable, it's not practical. The point of using an
RCD in this situation is that it overcomes the possible problem with
the slowness of the MCB (and offers other protection as well).

--
Chris Green )