what is the principal of star delta starter?

Answer Posted / amit vishwakarma

Star delta starter used for squirrel cage motor,utilises the principle of reducing the starting voltage.all the six terminals( each of two) of 3 phase induction motor are brought to the starter ......
             In fact start delta starter is simply a two way switch. The method is based upon the principle that with 3- winding  connect in star, the voltage across each winding is 1/√3..i.e.57.7% of the line to line voltage whereas, the same winding connected in delta will have full line to line voltage across each.
     The star delta starter connects three stator winding in star across the rate supply voltage at the starting instant. After the motor attain speed, the same winding through a change over switch are connected in delta across the same supply voltage..

Is This Answer Correct ?    7 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is voltage divider rule?

697


This is reqd for a 1MW Solar power plant..We have 2DC outputs from the solar panels Connected to 2INVERTOR panels.. Output from invertor is 3ph,280v,500kva,50hz.These are connected to individual ACB.This has to be stepped up to 11KV ,1250KVA SYSTEM.Now can I use (1) one more ACBTO GIVE A COMBINED OUTPUT OF 1000KVA,280V & STEP UP THE OUTPUT BY USING a single two winding 3 ph transformer 11kv/1250kva. or (2)use the two outputs and connect to one three winding transformer of above rating..Pls suggestwith details.

1995


Name two low frequency oscillators?

893


What is the differentional relay...what is the work of this in power Tx. how it is works..

1438


how i chosse capacitor bank if my energy meter is 48 kvr? tell me capacitor bank chossen formula?

1909






Why we use circular(Stepped) cross section in transformer core?

1749


What is the maximum and minimum rating of UPS?

990


What is cut-off rate?

757


how does the thyistor work in dc drive?

1537


What happened ,If 3 phase clearance not maintained in 33KV Line,11KV LIne etc?

1811


what is cause of static electricity? I experience shock when i touch metal equipment in a room ,furher check shows earth leakage showing 80ma at the DB near to the 400 MCCB?

1439


testing of Vector Group – YNaoD II

2440


Which capacitor is preferred for high voltage and frequency?

585


I have a situation to design sub-Distribution board/Panel meant for feeding power sockets. In the incomer CAN i Take TP MCCB with Neutral Link and All the outgoing feeders with to sockets with TP MCCB and Neutral Link? P.S : My System is IT Earthing

1306


What is effect on in zone and out zone fault if CT chosen for phase side is Vk/2<5mA and Neutral side is Vk/2<15mA on REF protection of Transformer

1892