- The voltage of the local LV network may be 120/208 V or 240/415 V, i.e. - the lower or upper extremes of the most common 3-phase levels in general use, or at some intermediate level, as shown in Figure C.. - Afghanistan a) 380/220 (a) 380/220 (a). - Algeria e) 380/220 (a) 10,000. - Angola a) 380/220 (a) 380/220 (a). - Argentina a) 380/220 (a). - Armenia a) 380/220 (a) 380/220 (a). - Belarus a) 380/220 (a) 380/220 (a). - Bolivia k) 400/230 (a) 400/230 (a). - Botswana k) 380/220 (a) 380/220 (a). - Chile k) 380/220 (a) 380/220 (a). - China k) 380/220 (a) 380/220 (a). - Croatia a) 400/230 (a) 400/230 (a). - Denmark a) 400/230 (a) 400/230 (a). - Djibouti a) 400/230 (a). - Egypt a) 380/220 (a) 66,000. - Estonia a) 380/220 (a) 380/220 (a). - Finland k) 400/230 (a) 690/400 (a). - 400/230 (a). - Georgia a) 380/220 (a) 380/220 (a). - Germany a) 400/230 (a) 20,000. - Hong Kong k) 380/220 (a) 11,000. - Indonesia k) 380/220 (a) 150,000. - Iran k) 380/220 (a) 20,000. - a) 380/220 (a). - Ireland k) 400/230 (a) 20,000. - Israel a) 400/230 (a) 22,000. - Italy a) 400/230 (a) 20,000. - Jordan a) 380/220 (a) 400 (a). - 400/230 (k). - Kazakhstan a) 380/220 (a) 380/220 (a). - Kirghizia a) 380/220 (a) 380/220 (a). - Laos a) 380/220 (a) 380/220 (a). - Latvia a) 380/220 (a) 380/220 (a). - Lithuania a) 380/220 (a) 380/220 (a). - Luxembourg a) 380/220 (a) 20,000. - Macedonia a) 380/220 (a) 10,000. - 380/220 (a). - Madagascar k) 380/220 (a) 35,000. - Mauritania k) 400/230 (a) 400/230 (a). - Moldavia a) 380/220 (a) 380/220 (a). - Morocco a) 380/220 (a) 225,000. - Mozambique a) 380/220 (a) 6,000. - Niger k) 380/220 (a) 15,000. - Nigeria k) 400/230 (a) 15,000. - 400/230 (a) 380/220 (a). - Paraguay k) 380/220 (a) 22,000. - Philippines (Rep of the j . - Poland k) 400/230 (a) 1,000. - 380/220 (a) 380/220 (a) 220 (k). - Russia a) 380/220 (a) 380/220 (a). - Rwanda k) 380/220 (a) 15,000. - Samoa 400/230. - 380/220 (a a). - Senegal a) 380/220 (a) 90,000. - Serbia and Montenegro a) 380/220 (a) 10,000. - Seychelles a) 400/230 (a) 11,000. - Sierra Leone k) 400/230 (a) 11,000. - Singapore a) 400/230 (a) 22,000. - Slovenia k) 380/220 (a) 10,000. - 400/230 (a . - 380/220 (a . - 400/230 (a) 380/220 (a) 380/220 (a). - Sri Lanka k) 400/230 (a) 11,000. - Swaziland k) 400/230 (a) 11,000. - Sweden a) 400/230 (a) 6,000. - Switzerland a) 400/230 (a) 20,000. - Tadzhikistan a) 380/220 (a) 380/220 (a). - Tanzania a) 400/230 (a) 11,000. - Tunisia a) 380/220 (a) 30,000. - Turkmenistan a) 380/220 (a) 380/220 (a). - Turkey a) 380/220 (a) 15,000. - a) 380/220 (a) 380/220 (a). - 380/220 (a) 415/210 (a). - United Kingdom k) 400/230 (a) 22,000. - United Kingdom k) 400/230 (a) 400/230 (a). - Vietnam k) 380/220 (a) 35,000. - Zambia k) 380/220 (a) 380 (a). - b The location along the distribution network of the proposed new load, i.e. - close to the substation, or near the remote end of the distribution network, etc. - This arrangement provides a very flexible system in which a complete substation can be taken out of service, while the area normally supplied from it is fed from link boxes of the surrounding substations.. - Figure C (next page) shows the main features of the two systems.. - The utility/consumer interface is often at the outgoing terminals of the meter(s) or, in some cases, at the outgoing terminals of the installation main circuit-breaker (depending on local practices) to which connection is made by utility staff, following a satisfactory test and inspection of the installation.. - Closing and tripping of the MCCB is freely available to the consumer, so that if the MCCB is inadvertently tripped on overload, or due to an appliance fault, supplies can be quickly restored following correction of the anomaly.. - In the field of electronic metering, techniques have developed which make their use attractive by utilities either for electricity metering and for billing purposes, the liberalisation of the electricity market having increased the needs for more data collection to be returned from the meters. - The quality of the LV network supply voltage in its widest sense implies:. - In most countries, power-supply authorities have a statutory obligation to maintain the level of voltage at the service position of consumers within the limits of ± 5% (or in some cases ± 6% or more-see table C1) of the declared nominal value.. - The voltage drops in a typical distribution system occur as follows: the voltage at the MV terminals of a MV/LV transformer is normally maintained within a ± 2% band by the action of automatic onload tapchangers of the transformers at bulk-supply substations, which feed the MV network from a higher-voltage subtransmission system.. - The voltage band at the output terminals of the fully-loaded transformer will therefore be (102 - 3.4. - As a matter of interest, the maximum rating of the cable, based on calculations derived from IEC is 290 kVA, and so the 3.6% voltage margin is not unduly restrictive, i.e. - 105% of the nominal voltage. - In principle the lowest losses in a power system are attained when all parts of the system operate at unity power factor. - b Reduction of the peak power demand, while increasing the demand at low-load periods, thereby exploiting the generating plant more fully, and minimizing plant redundancy. - Since, for a given kW loading, the minimum value of kVA occurs at unity power factor, the consumer can minimize billing costs by taking steps to improve the power factor of the load (as discussed in Chapter L). - b Certain hours during the 24-hour day b Certain periods of the year. - A contactor, operated by the same timing device, closes the circuit of the water heater, the consumption of which is then indicated on the register to which the cheaper rate applies. - In such schemes the ratio of cost per kWh during a period of peak demand for the year, and that for the lowest-load period of the year, may be as much as 10: 1.. - Instead of the dial being marked in kVAh at that point however it can be marked in units of average kVA. - At the end of the billing period, the red indicator will be at the maximum of all the average values occurring in the billing period.. - Electro- mechanical meters of the kind described are rapidly being replaced by electronic instruments
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