Hi All, There was some discussion a few days ago on the voltage of UK electricity supply system. If the following has been said before, then I apologize for taking the bandwidth. The UK, as from the early 1990's, has a declared nominal voltage of 230V with a tolerance of +10% and -6%. Prior to that, it was 240V +/- 6%. If you are in the UK, then your supply voltage should be somewhere between 216V and 253V. The actual values will vary depending on where you are located and the time of day. Although, in principle it was intended to eventually bring in a declared 220V, to align more closely with Europe, there are no immediate plans for this. The foregoing has been confirmed with OFFGEM, the official regulator's office. If you're in the UK, and your supply voltage is outside the limits, then in the first instance contact your electricity supplier. Many new power supply units, for computers and audio equipment etc. used switched mode techniques, and the actual operational supply voltage for any one of these units can have a very wide range, 100V to 250V for instance. However, if you have an older power supply unit incorporating an iron cored transformer, rectifier, linear regulators, etc. then be aware of the frequency requirements if purchasing a 100 to 230V step up/step down transformer. Much of the world's electricty supply systems run at 60 Hz, but the UK runs at 50 Hz. If you use a transformer designed for 60 Hz systems, then it is likely to have less iron than an equivalent transformer designed for 50 Hz. Its impedance will therefore be lower, and it will get very hot if run on 50 Hz, and its useful life may not be very long. The UK electricity supply meter measures kilowatt/hrs. The watt is 'a measure of the rate of doing work'. When I was at school we had experiments with churning paddles in tanks of water, and passing dc current through heating coils, etc. associated with this. Without going into ac electrical circuit theory for an explanation, I can assure you that you will not get any electrical power for free by using capacitors or inductors to shift the current out of phase with the voltage. Larger industrial loads, which by their nature can be highly inductive, are metered and billed on a different tariff, since the supply authority cables and other equipment have to be able to carry the proportionally heavier current that this requires, as compared with a load of the same power, but with voltage and current in-phase. Hope this helps, Best wishes, Ray ----------------------------------------------------------------- To stop getting this list send a message containing just the word "unsubscribe" to [EMAIL PROTECTED]
