Wiring for 240V AC in mobile accomodation
 

We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

Wiring for 240V AC in mobile accomodation
 

VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.



I once got an electric shock when i put the key in the door of my bus-
rubber tyres, me standing on the ground-
so now i hammer a spike into the ground and attach an earth wire to it..

I wonder what the experts will say?

[g]

Wiring for 240V AC in mobile accomodation
 

"george (dicegeorge)" wrote in message
...


VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers
etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

I once got an electric shock when i put the key in the door of my bus-
rubber tyres, me standing on the ground-
so now i hammer a spike into the ground and attach an earth wire to it..

I wonder what the experts will say?


Thanks George,

I need, and other users need, to avoid electric shocks but for other reasons
a ground spike is not feasible.
VaBene

Wiring for 240V AC in mobile accomodation
 

In article ,
VaBene wrote:
I need, and other users need, to avoid electric shocks but for other
reasons a ground spike is not feasible.

Make up a steel plate, connect to generator earth, and park one wheel over
it.

--
*A snooze button is a poor substitute for no alarm clock at all *

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

Wiring for 240V AC in mobile accomodation
 

In article ,
"VaBene" writes:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

Just a warning -- horses and other livestock are extremely
sensitive to electric shock (more so than humans), and it's
important that any design or changes to the wiring are made
by someone who is aware of the methods used to prevent
electrocution of livestock.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Wiring for 240V AC in mobile accomodation
 

VaBene wrote:

We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.


If you connect the generator neutral line to the vehicle chassis, your
RCD will act on any shock from the live, it will be fully effective.
Your earth connection is then also the vehicle chassis. This is an IT
system.

Connection to external ground isn't needed if the electrics are
contained wholly within the vehicle. However if leads to the ouside
are used then you do need to earth the vehicle chassis.

PS there's a chance that one side of the gen already connects to
chassis, and it might be the one you're currently treating as 'live.'
If so, grounding the neutral would pop the breaker. If this happens,
ground the other gen output line instead, and make sure your fusing
etc is in what is now the live line.

All this describes the practicalities of portable generator fault /
shock protection rather than being a statement of the full
requirements of the 17th edition, which will be more demanding in your
case.

PPS you'll want a passive RCD, not an active one. If you get the wrong
type you'll have to press the reset button every time you start the
gen to get power.


NT

Wiring for 240V AC in mobile accomodation
 

On Tue, 27 Jan 2009 23:02:08 -0000 someone who may be "VaBene"
wrote this:-

We have a horsebox with living accomodation.

The 17th Edition covers installations where animals are present and
caravans. I imagine that horses are valuable to you. If this is the
case then pay someone to give you advice, not a house electrician
but someone who understands the issues.

Large four legged animals are particularly vulnerable to voltage
gradients.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Wiring for 240V AC in mobile accomodation
 

VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.


If you ground the Neutral *before* you take it to an RCD, it should work.

Wiring for 240V AC in mobile accomodation
 

On Tue, 27 Jan 2009 23:02:08 -0000, "VaBene"
wrote:

Should both the neutral and earth be wired to the chassis of the vehicle.

A number of generators output 240V as 120V either side of earth so the
line and neutral are each 120V different from their earth.

Wiring for 240V AC in mobile accomodation
 

On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

It will certainly be worth you getting hold of a copy of BS7671 and
reading up thoroughly on the particular requirements of section 717.
Page 206 shows a diagrammatic outline for use with a generating set
within or without the unit. Also worth reading up on Agricultural
installations in the same BS

Wiring for 240V AC in mobile accomodation
 

cynic wrote:
On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

If it is, grounding one leg will simply pop the breaker each time it
starts. If this happens, whichever leg you ground, then you'll know.


NT

Wiring for 240V AC in mobile accomodation
 

On 28 Jan, 15:42, wrote:
cynic wrote:
On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

If it is, grounding one leg will simply pop the breaker each time it
starts. If this happens, whichever leg you ground, then you'll know.

NT

If he has a generator with a centre tap connection to earth and he
then earths one output before his protective device the net result is
a short circuit of half of the output winding. Running the generator
engine will risk burning out that half winding. (Assuming the
generator will excite with a short circuit output - some do some don't)

Wiring for 240V AC in mobile accomodation
 

cynic wrote:
On 28 Jan, 15:42, wrote:
cynic wrote:
On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

If it is, grounding one leg will simply pop the breaker each time it
starts. If this happens, whichever leg you ground, then you'll know.

NT

If he has a generator with a centre tap connection to earth and he
then earths one output before his protective device the net result is
a short circuit of half of the output winding. Running the generator
engine will risk burning out that half winding. (Assuming the
generator will excite with a short circuit output - some do some don't)

I assumed the OP would be earthing the gen after its built-in breaker
rather than taking the gen apart. If it were shorted pre-breaker, and
the excitation system still functioned, the engine would simply stall.


NT

Wiring for 240V AC in mobile accomodation
 

On 29 Jan, 00:56, wrote:
cynic wrote:
On 28 Jan, 15:42, wrote:
cynic wrote:
On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

If it is, grounding one leg will simply pop the breaker each time it
starts. If this happens, whichever leg you ground, then you'll know.

NT

If he has a generator with a centre tap connection to earth and he
then earths one output before his protective device the net result is
a short circuit of half of the output winding. Running the generator
engine will risk burning out that half winding. (Assuming the
generator will excite with a short circuit output - some do some don't)

I assumed the OP would be earthing the gen after its built-in breaker
rather than taking the gen apart. If it were shorted pre-breaker, and
the excitation system still functioned, the engine would simply stall.

NT- Hide quoted text -

- Show quoted text -

I don't recall any mention of a built-in breaker and certainly my 1.5
kVA geny does not have one. The risk of burning out the winding
remains as I seriously doubt mine with its 4 stroke engine and
throttle governor would stall under the described conditions. The OP
can make his own mind up if he wants to take the risk. Not knowing
exactly what model he has I will not make assumptions.

Wiring for 240V AC in mobile accomodation
 

cynic wrote:
On 29 Jan, 00:56, wrote:
cynic wrote:
On 28 Jan, 15:42, wrote:
cynic wrote:
On 28 Jan, 09:00, The Natural Philosopher wrote:
VaBene wrote:
We have a horsebox with living accomodation.
On board 240V generator to power lights, 13A sockets, battery chargers etc.
Is there a way that an RCD, or similar device, can be incorporated to
protect any person in case they come into contact with live at any point?
Should both the neutral and earth be wired to the chassis of the vehicle.

If you ground the Neutral *before* you take it to an RCD, it should work.

There has been much useful advice already given but it is worth saying
that "some" generators deliver from a centre tapped output winding.
Make certain yours is not one of them.

If it is, grounding one leg will simply pop the breaker each time it
starts. If this happens, whichever leg you ground, then you'll know.

NT

If he has a generator with a centre tap connection to earth and he
then earths one output before his protective device the net result is
a short circuit of half of the output winding. Running the generator
engine will risk burning out that half winding. (Assuming the
generator will excite with a short circuit output - some do some don't)

I assumed the OP would be earthing the gen after its built-in breaker
rather than taking the gen apart. If it were shorted pre-breaker, and
the excitation system still functioned, the engine would simply stall.

NT- Hide quoted text -

- Show quoted text -

I don't recall any mention of a built-in breaker and certainly my 1.5
kVA geny does not have one. The risk of burning out the winding
remains as I seriously doubt mine with its 4 stroke engine and
throttle governor would stall under the described conditions. The OP
can make his own mind up if he wants to take the risk. Not knowing
exactly what model he has I will not make assumptions.

What voltage does the genny winding drop at full load? 10%? Most
likely rather less. That means even on a relatively high resistance
gen, if shorted it would supply 10x rated curent at normal run speed.
If the OP has a generator thats physically capable of doing even a
fraction of that speed under such a load, then s/he has a remarkably
badly designed gen bought from a company that must have gone out of
business very fast indeed. In short, its unrealistic.


NT