Boiler for static caravan - no earth

[James Melville]

Hi, currently we have a static caravan with a generator running electric to the caravan. We also have a boiler which lately have been having alot of problems with. Had plumbers out etc but still cuts out. I have an earth stake in the ground with 10mm earth to caravan fuseboard. Testing at the board 230v between live and neutral but 120v from live to earth! Does this mean the earth stake isn't deep enough in the ground or something wrong. Have found out that the boiler Infact needs an earth for it to function properly as has an electronic ignitor. So without a proper earth into the carvan the boiler becomes faulty. I have heard somewhere that generators have a floating earth and some people have said to link neutral and earth at the generator in order to get the boiler working. What other options is there.

 

[James]

This is likely to be a problem with the N not being tied to earth.
Have you tested earth loop impedance?

 

[James Melville]

This is likely to be a problem with the N not being tied to earth.
Have you tested earth loop impedance?

Was unable to test earth loop because it is saying there is no earth at any of the socket outlets and at the fuseboard

 

[Strima]

What size generator?

 

[pc1966]

Small generators often are floating supplies. Check with it's documentation to see if it should be providing the N-E link.

 

[James Melville]

What size generator?

3800kw generator

 

[James Melville]

Small generators often are floating supplies. Check with it's documentation to see if it should be providing the N-E link.

Where would u put this n-e link

 

[suffolkspark]

Is the generator staked?

 

[James Melville]

Yes I have earth staked the generator as well as put a earth for the caravan but testing inside caravan says there isn't a earth

Is the generator stake

 

[pc1966]

Check at the generator to see if the N & E are linked. If you have the manual (or make+model to search on-line) it might say how it is configured.

If you are feeding a single load than an IT (isolated) supply has some obvious safety advantages and allows systems to continue under single fault conditions, but it is not good for more than one load unless fitted with insulation monitoring and under competent supervision (e.g. ship supply, hospital theatre supply, etc).

 

[loz2754]

The On Site Guide has a good section on earthing of generator sets. A floating earth is not to be used to supply more than one item of class 1 equipment, so a neutral to earth link will be needed I think.

 

[Strima]

3800kw generator

Is that 3800kW, 3.8kW, 3800W or 3.8kVa?

Sounds like the generator has no N-E link.

What's the make and model?

 

[James Melville]

Is that 3800kW, 3.8kW, 3800W or 3.8kVa?

Sounds like the generator has no N-E link.

What's the make and model?

Its a Chinese one I think. Senci 400i I think

 

[James Melville]

Its a Chinese one I think. Senci 400i I think

Yea 3800 Watts 3.8kw

 

[marcuswareham]

As mentioned above the generator probably doesn't have L-N linked , Iv owned a few small (under 15 KVA) generators and all of them have not had a L-N link. The earthing point on the chassis of the generator just connects to the cpc/earth pins of the outlets,

The earth in this case is basically a bonding conductor and making sure if there is a fault then the earth for each appliances is at the same potential, and the set up is normally isolated from true earth (see attached picture)

It is normally very easy to see if the generator is this configuration by just removing the cover on the part with the socket outlets, obviously with the generator off