Power Engineers Window

Neutral absent in two phase T hree lamps L1, L2 and L3 of 250 Volts 100 Watts are connected in star formation across three phase 433 Volts AC supply as in following diagram. Star point C of lamps is connected to neutral. Switch S1 is in phase B and Switch S2 is in Neutral as shown. Circuit Diagram   What happens when Switch S1 is ON and switch S2 is ON Switch S1 is ON and switch S2 is OFF Switch S1 is OFF and switch S2 is ON Switch S1 is OFF and switch S2 is OFF Answer Readers, Quiz is a mental exercise to enhance reasoning power in the subject. Hence personal attempt for reply is expected before jumping to answer. Answer given here is just for confirmation. Proceed When switch S1 is ON, three phase supply is available. When switch S2 is ON, neutral is also available. Normal phase voltage i.e. 433 ÷ √3 = 250 is available across each lamp and therefore each lamp glow as normal at rated voltage. When switch S1 is ON and switch S2 is OFF, three pha...

Neutral line Current  Three phase four wire supply R,Y, B & N is available. Identical Load L drawing 5Amps is connected between each phase and neutral as in diagram. Ampere meters are connected in three section of the neutral as shown. Circuit Diagram Value of current I 1 , I 2 & I 3 is to be estimated. ANSWER

Energy Saving Scope for Air Conditioners Darkness is absence of light. Similarly cool means absence of heat. So cooling is expelling heat from any space. Air conditioning systems are intended to evacuate heat from specific area called controlled area. Chill water plant, central ac plant and package units are installed for cooling big premises. For homes and offices, small units of 1 to 2 tones capacity are used. Window units used earlier are now obsolete and now split units are most common. Normally cooling area is a close room and air inside is circulated by AC. Flow of heat from higher temperature to lower temperature side is natural. But duty of air conditioner is to transfer heat from room at lower temperature to outside atmosphere at comparative higher temperature. This requires some trick to accomplish the objective.   The process required for cooling the room is similar to removing splashed water on floor of the room. This is done by spreading loose mop over t...