3 Phase Wiring in EU

[fidom]

I have been doing some rewiring of my house in Croatia and discovered that the supply from the meter is 3 phase but only one phase is currently in use. The other 2 phase wires are just hanging loose behind the board upon which the consumer unit is mounted. I think all the houses in the village were treated to a new supply and meter box quite recently so the previous supply must have been single phase.
I'm thinking perhaps I should make use of the other phases to correct the load imbalance. Will I need to observe the phase colour codes throughout the property (brown, black, grey) or can I just do all the live wires in brown? Some of the wiring in the loft is done with round, 3 core cable (the equivalent to UK T&E). For that would I need to find (for example) grey-blue-green/yellow cable or should I terminate the ends for that phase with grey sleeving?

 

[JohnD]

Have you got a three phase meter?

Have you got three service fuses connected?

 

[fidom]

As far as I know I don't have any service fuses. The meter is in a locked plastic box outside and I don't have a key. I don't know how to tell whether it's a 3 phase meter. The spare phase wires do light up the neon screwdriver though. The electric bill only gives one set of numbers but perhaps it shows the total figure for all phases?

 

[PBC_1966]

Forget about the neon screwdriver, as even with those cables completely disconnected it's liable to light up due to capactive coupling from the single live cable next to them. If the two cables are really just hanging loose behind the board (not terminated into anything) then I would really hope that they've not been left live!

I can't speak for Croatia specifically (either now or for when it was part of Yugoslavia), but in Europe in general the trend for smaller residential supplies has been more toward abandoning 3-phase systems and going to single phase, except where higher amounts of power are required. For example, in France in the past it wasn't at all unusual to find a 3-phase supply rated at just 15A per phase, whereas today a new supply of equivalent capacity would almost certainly be single phase.

I suspect, therefore, that's it's far more likely that the house used to have a 3-phase supply but is now on a single-phase supply, two of the original phase cables being abandoned in place. The bill would still show a single set of readings whether single or 3 phase, but if you look closely it may also indicate the type of service somewhere, assuming you can understand the language.