Lost in translation????

[wv62]

This is a warning sign on the outside of an inverter cubicle on a solar farm I worked at. It seems every cubicle by this company (a very well known multi national, not sure if I should name them as they employ me!) in the UK has the same sign. Do you think something was lost in translation??

 

[JohnW2]

Also, is it actually HV, in the IEC sense?

Kind Regards, John

 

[wv62]

The DC in is around 1000V and the outgoing varies depending on the DNO.

 

[JohnW2]

The DC in is around 1000V and the outgoing varies depending on the DNO.

1000V DC is obviously 'LV'. Is it likley that the output voltage would be greater than LV?

Kind Regards, John

 

[westie101]

Nice
Particularly when the wording should possibly be

"Danger of Death - Keep Off (or out)"

Solar farms will usually output to the DNO at 6.6 or 11kv. though we have just had one connected at 33kV
The control figure is the maximum load and the capacity of the local networks.
We have generation sites connected at 132kV in places

 

[JohnW2]

Nice ... Particularly when the wording should possibly be "Danger of Death - Keep Off (or out)"

Indeed - but maybe what they intended (but didn't get quite right!) was "Danger to Life" ?

Kind Regards, John

 

[westie101]

Oh I got that straight away

 

[ericmark]

Maybe written by Mary Shelley author of Frankenstein!

 

[plugwash]

The DC in is around 1000V and the outgoing varies depending on the DNO.

1000V DC is obviously 'LV'.

That depends on the earthing arrangements. A +-500V (relative to earth) system would be LV but a system with one end grounded and the other at 1000V relative to earth would be HV (by the BS7671 definition). I'm not sure about floating systems as "nominal voltage relative to earth" would be undefined in that case. I'm not sure if that means you should ignore the earth relative part of the definition or if you should assume the worst.

 

[wv62]

Maybe written by Mary Shelley author of Frankenstein!

Hmmm.....Just got an image of being chased around the field by an inverter

 

[JohnW2]

1000V DC is obviously 'LV'.

That depends on the earthing arrangements. A +-500V (relative to earth) system would be LV but a system with one end grounded and the other at 1000V relative to earth would be HV (by the BS7671 definition).

Eh? The BS7671/IEC definition of LV goes up to 1500V DC, doesn't it?

I'm not sure about floating systems as "nominal voltage relative to earth" would be undefined in that case. I'm not sure if that means you should ignore the earth relative part of the definition or if you should assume the worst.

Indeed. The BS7671 definitions really 'fail' when the supply is floating relative to earth!

Kind Regards, John

 

[plugwash]

1000V DC is obviously 'LV'.

That depends on the earthing arrangements. A +-500V (relative to earth) system would be LV but a system with one end grounded and the other at 1000V relative to earth would be HV (by the BS7671 definition).

Eh? The BS7671/IEC definition of LV goes up to 1500V DC, doesn't it?

AIUI it's 1500V between conductors but only 900V relative to earth.

 

[JohnW2]

AIUI it's 1500V between conductors but only 900V relative to earth.

Ah, yes - I forgot about the 900V

Kind Regards, John

 

[ban-all-sheds]

Here's a suggested warning notice:

It avoids all the problems with ELV/LV/HV terminology and has the added bonus of meaning electricians only need to carry one type.

 

[westie101]

Or just use the one used by the whole supply industry in Europe - yep that's right
http://www.legislation.gov.uk/uksi/2002/2665/schedule/1/made

We just add the words Keep Off or Keep Out in the size specified in the regulations