Electricity Supply wrong voltage?

The very first thing I recommend is employing a translator when dealing with important issues. It will probably cost you around €20 for the hour.

Steve 

Perhaps your builder is referring to the maximum amount of electricity you can use at any given time and is measured in kW or Kilowatts, this is sometimes referred to as Potencia in Spain and will typically be 3.45kW, 4.6kW, 5.7kW, although higher levels are available, do you know who the electricity supplier is, as they for a fee, will inform you what potencia is needed and if given the work will certify the installation.

Define "quite a number of years ago".

On the face of it it sounds like it may be a case of a property built for a now pretty obselete 3 phase supply but with only a single phase supply now available, or vice-versa.

Ultimately you need an electrician who speaks English.

Hi Ede1001 and welcome to the forum!

I agree with Darro, you need a good electrician to investigate and explain the issue to you.  I´d recommend Tony Poole from Sparks in Spain:

https://www.sparksinspain.es/

I've used him many times, he's knowledgeable, legal, and reasonably priced.  I suggest dropping him an email to explain your situation.

Kind regards,

Kim

Kind regards,

Kim

Hi Edel,

Step one, get an English speaking electrician to have a look and then explain to you what the problem is. Right now you don’t even know what the problem is. Irrespective of recommendations including mine, which are based upon quality of service provided, don’t just have one electrician have a look. No matter how nice their web site is, They will normally provide an inspection and free estimate. I was almost ripped off by a very reputable company who came to check things out when we wanted upgrading from 3.45 to 5.7 KW, wanted them to provide the boletin. (A document issued that confirms that your existing electrical installations comply with Spanish elect regs, and therefore fit for an upgrade) He charged me up front for the estimate, but could be deductible from the final cost if I used them. Then went on to explain all the wiring upgrades that were necessary, searched the whole property for any additional things he could possibly add on, and ended up with a stupid price. But even if I used him or not, he still had the money for the estimate in his pocket. Luckily I had two other companies also look at the job, both gave similar estimates to each other, no wiring upgrade required, and didn’t charge up front for the check. I chose one of them, and he arranged the boletin, no additional work required. So don’t just trust one company, irrespective of their UK qualifications, how long they have been in the business and a nice web site. Get three estimates, it makes sense. I have had both these electricians work for me, Amps electrical, [email protected] / www.amps-electrical.com. Also Marcus (English/Spanish/ Dutch speaking) 680857349, extremely professional and contacts in Iberdrola, and used by several key holders as their electrician to go to!. Both in your area, it’s true what they say, provide a good service and you will reap the benefits, just  by word of mouth. Hope this helps, Hew.

Hi Ede1001,

Absolutely agree with Hew, always get at least 3 quotes - there are a lot of cowboys out there, so personal recommendations for qualified and legal companies are important.

Also, make sure you know what is included in the price, especially if it transpires that an upgrade is required to solve the problem.  Some people may not understand that the "Boletin" (electrical safety certificate) makes the electrician who issued it responsible for the end to end installation.  If the worst should happen after an upgrade and you have an electrical fire, the house insurance won’t pay out and you'll be left having to sue the electrician.  A competent electrician must test all of the existing installation, as they will be certifying the integrity of the entirety of it.

Kind regards,

Kim

Even some extremely competent electricians will try and make as much money from you as possible. That includes quoting for, and attempting to carry out unnecessary work. Unless you have a comparison to judge it by, you could be out of pocket. Of  course you will still get the certification, which is legally valid, but it has cost you a lot more than necessary. Hence the requirement for several quotes. Irrespective of who has recommended them. 

Hi Hew,

Yes, that's why I agreed with you; although it's not just about getting more than one quote, it's also ensuring that the quotes are comparable, hence the need to ask what is included in each quote.  It never ceases to amaze me how many people are happy to commit to work based purely on a price, without a written quotation against which they can confirm that works have been correctly - and completely - carried out.

Kind regards,

Kim

Hi Kim,

Agree as far as ensuring that the quotes are comparable, but when I got a quote from a very well known electrical service provider,  I had seen them advertised and recommended many times on several forums, including this one. The quote he gave me for work to be carried out was confirmed by two other reputable companies as not required.  We are talking somewhere in the region of over three times the price. So in that instance having a few quotes, not just going by others recommendations (who may well be biased and have some connection with the service provider) was the most important factor. 
Cheers, Hew.