Line Voltage Control - double contactor three phase motor starter controlling a reversible three phase motor (rev 08 Aug 2006) (Note: L1 becomes T3 and L3 becomes T1 when the reverse relay is actuated.) The motor must be STOPPED before REVERSING unless the contactor allows for on-the-fly reversing. The coils are locked out via the NC contacts (M1, M2) usually contained within the mechanical interlock. When Coil #M1 is engaged, Coil #M2 is locked out and vice-versa.
Line Voltage Control three phase (3ph) motor starter controlling a single phase motor (rev 08 Aug 2006) Some 3 phase Magnetic Motor Starters require current to be seen across each of the three overloads. This may be accomplished by directing the output of second circuit back into the input of the third (previously unused) circuit and feeding the motor off of the output of the third circuit (rather than the second). Wiring then becomes: Line 1 → L1 → T1 → Motor 1 (L1-hot 240v or neutral 120v) Line 2 → L2 → T2 → L3 → T3 → Motor 2 (L2-hot 120v or 240v)
Manual Starter? Merely ignore the control wiring in RED
Recently interest has grown in the burning of garbage / domestic waste to produce electricity. This is not a new idea although in the past when waste was burned it created pollution that could even be toxic. Today, the technology exists to remove almost all the pollutants from the fumes produced during the energy production cycle. Special filters remove dangerous chemicals and particles that would normally be found in the fumes.
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1. The domestic waste is sorted usually by hand to remove materials than can be recycled. Steel is removed using electromagnets and this is stored until there is enough quantity for recycling to be economically viable. Aluminium, in the form of cans is removed by hand. Other recyclable materials are collected separately. These include, garden waste, newspapers, cardboard, bottles, waste food and even used batteries.
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2. The waste is then ‘dropped’ into the hopper of a furnace. When the doors slide open it falls into the burning chamber. Gas is normally used to start the fire which burns at a high temperature, destroying the domestic waste.
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Whilst the waste burns it heats a water tank, in turn, producing steam. The steam is used to turn turbines, producing electricity.
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Once steam has been produced, the production of electrical power is no different than that used in any other power station. The high pressure steam is used to turn electrical turbines which produce electricity. The advantage of this way of producing electricity is that the domestic waste that would normally be buried in land fill sites or even dumped far out at sea, is burned. This means that vast areas of land that would have to be used for land fill are free for agriculture or for building.
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The domestic waste is burned in the furnace. This heats water in a tank producing steam. The high pressure steam is used to turn turbines, producing electricity. The steam produced during the process condenses back to water and is recycled for heating once again. Pollutants are removed from the fumes before they are allowed into the atmosphere.
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TRANSISTORS A transistor is a semiconductor device that contains three regions separated by two distinct PN junctions. The two junctions are...
