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| The new nominal supply across the UK and Europe will be 230V ± 10% (an effective reduction in the UK nominal supply voltage) the initial stage was implemented in 1995 with the full implementation by January 2003. This was postponed until January 2008 and then yet again without any new set date but relying on consensus between interested parties. |
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| In 1996 the IEEE recommended equipment manufacturers to allow an additional 4% reduction taking into consideration the voltage drop across a site. This was again extended within the UK with the introduction of the new 17th edition of IEEE Wiring Regulation and it is now generally considered that 230V -15% +10% (195.5V to 253.0V) would be a more appropriate level to ensure correct operation. Manufacturers supplying into the UK and Europe markets (CE marked) will at least have to ensure their equipment will function correctly at the extremes of both sets of present day statutory limits. |
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Despite changes to the UK statutory supply level there has not been any reduction to our LV supply network levels and the average incoming voltage still stands at 242V. It is not unusual to see voltages in excess of 250V and some sites have recorded voltages in excess of 260V. There are many influences on the incoming voltage level of this typical retail site (Fig. 1) most associated with I2R losses, not just this site own operational characteristics but also those around it. The graph highlights the differences between day and night levels but also the weekend when other sites are non-operational. Another aspect worth noting is the imbalance of the phase voltages another cause of inefficiency. Now consider, a 230V rated lamp operated at 240V will consume 9% more energy than necessary but will only achieve 55% of its life. A cost paid by the consumer.
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| Figure 1 |
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