New Star Delta Forward Reverse

1. Three Phase Motor Connection Star/Delta (Y-Δ) Reverse and Forward with Tier Power ! Control Dia"ra  #s we have have alread$ alread$ shared shared the Startin" the  Startin" ethod o% Three Phase Motor &$ Star Delta Starter with Tier  Circ'it  Circ'it (Power and Control Circ'its). ow in the &elow dia"ras Three *hase Motor will rotate in two directions vi+ Forward and Reverse. ,'t e have controlled the direction o% rotation o% this three *hase otor &$ a Tier circ'it. Abbreviations: / 0 ver oad Rela$  0 orall$ *en C 0 orall$ Close FR 0 Forward R2 0 Reverse T 0 Tier  3 Phase Motor Connection Star/Delta (Y-Δ) Reverse / Forward with Tier Power Dia"ra Dia"ra

Power Diagram :

3 Phase Motor Connection Star/Delta (Y-Δ) Reverse / Forward with Tier ControlDia"ra

Control Diagram:

http://www.electricaltechnology.org/2014/06/Three-Phase-Motor-Star-Delta-Reverseorwar!-Ti"er-Power-Diagra".ht"l

CTR C4RC54T F # ST#R DT# R Y DT# FR#RD R2RS CTR4C MTR CTRR - # ,#S4C 4D5STR4# PRCSS #5TM#T4 CTR 6 T D 754D FR R2RS4, ST#R (Y) DT# MTR CTRR 2.

Sostenes $e%&le S&n!ay' (pril 1)' 201*

(n electrical sche"atic !iagra" +or the power circ&it o+ a reversi,le star !elta or wye !elta "otor controller was tac%le! in o&r previo&s article' where it showe! an ill&stration o+ the wiring co",inations &sing three  phase circ&it ,rea%ers' "agnetic contactors an! ther"al overloa! relay to achieve the !ierent variation o+ "otor TRM3($ connections in star an! !elta cong&ration in relation to the three  phase s&pply so&rce voltage' hence the ter" power circ&it !iag ra".

(s with all "otor controllers' the power circ&it is always acco"panie! with its associate! control circ&it which is an integral part o+ the "otor controller that provi!es operator co""an! access in or!er to control the power circ&it either in r&nning or stopping the "otor or selecting the +orwar! or reverse rotation o+ the "otor.

 The electrical !iagra" ,elow shows an sche"atic ill&stration o+ a +orwar! reverse star !elta or wye !elta control circ&it &se! in every electrical in!&stry involving in!&strial process a&to"ation control technology.

lectrical Sche"atic Diagra" +or the 5ontrol 5irc&it o+ a orwar! Reverse Star ye Delta Motor 5ontroller

Depen!ing on the choice o+ the operator' starting the circ&it is selecte! via the +orwar! or the reverse p&sh ,&tton switches. hen the +orwar! p&sh ,&tton switch is selecte!' the co""an! is trans+erre! to the relevant +orwar! +&nction o+ the circ&it which activates the +orwar! "ain coil ,l&e. The relevant a&7iliary contacts o+ the +orwar! "ain coil ,l&e wo&l! then ,e act&ate! opposite its nor"al state' that is' a nor"ally open contact wo&l! event&ally switch to a close contact whereas a nor"ally close contact wo&l! switch to an open contact.

 The +orwar! "ain contact ,l&e closes to activate the star coil ,rown together with the ti"er coil green' hence placing the "otor TRM3($

in the power circ&it

connecte! to a star cong&ration. (+ter an elapse! ti"e is reache!' the ti"er contact green will release the star coil ,rown an! trans+ers the co""an! to the +orwar! !elta "o!e as a res< o+ a co"plete! circ&it with the closing o+ the ti"er contact green along with the awaiting initially close! +orwar! "ain contact ,l&e' there,y per"itting power 8ow to the +orwar! !elta coil !ar% ,l&e. This nal stage places the "otor ter"inal in the power circ&it cong&re! to a !elta connection.

(nother +orwar! "ain contact ,l&e is connecte! in parallel across the +orwar! p&sh ,&tton switch to serve as a latching switch that %eeps the +orwar! "ain coil "aintaine! energi9e! a+ter the operator releases the +orwar! p&sh ,&tton switch.

5onversely' when the reverse p&sh ,&tton switch is presse! ,y the operator' all the relate! contacts o+ the reverse "ain coil re! is activate! which hol!s the reverse "ain coil "aintaine! activate! a+ter releasing the reverse p&sh ,&tton switch' then energi9es the star coil ,rown an! the ti"er coil green' then switches to the reverse !elta "o!e orange a+ter the specie! ti"e set on the ti"er e7pires.

 To "an&ally interr&pt the circ&it' the operator only nee!s to press the stop p&sh ,&tton switch to !eactivate any energi9e! coil in the control circ&it to instantaneo&sly isolate the power so&rce to the "otor. (nother interr&pting contact is the ther"al overloa! contact p&rple which serves as an a&to"atic sh&to switch that instantaneo&sly opens the control circ&it to sh&t !own the "otor when overloa! c&rrent greater than the rate! capacity is !etecte! +ro" the electric "otor.

nterloc% contacts are also strategically place! on the control circ&it as a protective "eas&re. (n a&7iliary contact +ro" the star contactor ,rown is connecte! in series ,e+ore the two !elta contactor coils to isolate ,oth the +orwar! !elta coil an! the reverse !elta coil when the star contactor coil is (5T . $i%ewise' a&7iliary contacts +ro" ,oth the +orwar! an! the reverse !elta coils are also place! in series ,e+ore the star coil to isolate power to the star coil sho&l! any one o+ the two !elta coils ,e active to ens&re the a,sence o+ power 8ow to the star coil when the control circ&it is actively in the !elta "o!e.

(&7iliary contacts +ro" ,oth +orwar! an! reverse coils are also place! opposite each coil so that one cannot activate witho&t the other one !eactivate! rst' "eaning' the nor"ally-close! +orwar! "ain contact ,l&e connecte! ,e+ore the reverse "ain coil re! will not per"it the(5T(T;3

o+ the reverse "ain coil re! while the +orwar!

"ain coil ,l&e is activate!' conversely' the nor"ally-close! reverse "ain contact re! connecte! ,e+ore the +orwar! "ain coil ,l&e will not also per"it the (5T(T;3   o+ the +orwar! "ain coil ,l&e while the reverse "ain coil re! is activate!.

 The sa"e con!ition applies to ,oth the +orwar! an! the reverse !elta coils. The opposing interloc% contacts place! ,e+ore the +orwar! an! the reverse !elta coils also provi!es protective action ,y preventing the si"<aneo&s activation o+ the +orwar! an! the reverse !elta coils at the sa"e ti"e' that is' the nor"ally-close! reverse "ain contact re! connecte! ,e+ore the +orwar! !elta coil !ar% ,l&e will not per"it the activation o+ the +orwar! !elta coil !ar% ,l&e while the reverse "ain coil re! is active' an! the nor"ally-close! +orwar! "ain contact ,l&e place! ,e+ore the reverse !elta coil re! will not also per"it the activation o+ the reverse !elta coil re! while the +orwar! "ain coil ,l&e is active.

 To +acilitate +or a +&rther &n!erstan!ing a,o&t the concept o+ the +orwar! reverse star !elta electric "otor control circ&it' a 8owchart !iagra" is provi!e! to serve as a sche"atic representation o+ the se