Vrftsjtryk

I am making the delta and star connections in circuitikz. But I have some problems stylizing ...

For the Star Connection:

documentclass[border=3mm]{standalone}

usepackage{circuitikz}

begin{document}

begin{circuitikz} draw



(2.5,1.5) node[circ, scale=0.6] (circ-a1) {a}

(0,1) node[circ, scale=0.6] (circ-a2) {a}

(2.5,1) node[circ, scale=0.6] (circ-b1) {b}

(1.5,1) node[circ, scale=0.6] (circ-b2) {b}

(2.5,0) node[circ, scale=0.6] (circ-c1) {c}

(0.75,0) node[circ, scale=0.6] (circ-c2) {c}

(2.5,0.5) node[circ, scale=0.6] (circ-n1) {N}

(0.75,0.5) node[circ, scale=0.6] (circ-n2) {N}

(circ-c2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-n2)

(circ-n2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-b2)

(circ-n2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-a2)

(circ-b1) -- (circ-b2)

(circ-c1) -- (circ-c2)

(circ-n1) -- (circ-n2)

(circ-a1) -- ++ (-2.5,0) -- (circ-a2)



;end{circuitikz}

end{document}

And for the Delta:

documentclass[border=3mm]{standalone}

usepackage{circuitikz}

begin{document}

begin{circuitikz} draw



(2.5,1.5) node[circ, scale=0.6] (circ-a1) {a}

(1,1.5) node[circ, scale=0.6] (circ-a2) {a}

(2.5,0.5) node[circ, scale=0.6] (circ-b1) {b}

(2,0.5) node[circ, scale=0.6] (circ-b2) {b}

(2.5,0) node[circ, scale=0.6] (circ-c1) {c}

(0,0.5) node[circ, scale=0.6] (circ-c2) {c}

(circ-b2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-a2)

(circ-c2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-a2)

(circ-c2) to[/tikz/circuitikz/bipoles/length=0.7cm, sV, scale=0.5] (circ-b2)

(circ-a1) -- (circ-a2)

(circ-b1) -- (circ-b2)

(circ-c1) -- ++ (-2.5,0) -- (circ-c2)

;end{circuitikz}



end{document}

I would like the Indices to be observable without changing the size of the nodes. And there are some lines I would like to remove. Also I want to know if there is a way to place the polarity in the voltage sources. Something similar to these images:

with tikz is simpler than with circuitikz

documentclass{article}

usepackage{tikz}

usetikzlibrary{arrows}

tikzset{

 sV/.style = {circle, draw, fill=white,

              minimum size=6mm, inner sep=0pt, outer sep=0pt,

              node contents={Large$sim$}},

dot/.style = {circle,fill, minimum size=2mm,

              inner sep=0pt, outer sep=0pt,

              node contents={}},

cir/.style = {circle,draw, fill=white, minimum size=2mm,

              inner sep=0pt, outer sep=0pt,

              node contents={}}

        }

begin{document}

    begin{tikzpicture}

draw   (0,0) node (n) [dot,label={[text=red]above:n}]

              -- node [sV,label=right:$V_{cn}$] ++ (270:2)   node (c) [cir,label=below:$c$]

        (0,0) -- node [sV,label=above:$V_{bn}$] ++ ( 30:2)   node (b) [cir,label=above:$b$]

        (0,0) -- node [sV,label=above:$V_{an}$] ++ (150:2)   node (a) [cir,label= left:$a$];

draw[-o]   (a) |- ++ (4.5,1)         node[right,text=red] (a')  {A};

draw[-o]   (b)  -- (b -| a'.west)  node [right,text=red] {B};

draw[-o]   (n)  -- (n -| a'.west)  node [right,text=red] {N};

draw[-o]   (c)  -- (c -| a'.west)  node [right,text=red] {C};

    end{tikzpicture}



bigskip

    begin{tikzpicture}

draw   (0,0) -- node [sV] ++ (2,0)     node (b) [dot,label=below:b]

              -- node [sV] ++ (120:2)   node (c) [dot,label=above:c]

              -- node [sV] ++ (240:2)   node (a) [dot,label=below left:a];

draw[-o]   (a) |- ++ (3,-1)   node[right] (a')  {a};

draw[-o]   (b)  -- (b -| a'.west)  node [right] {b};

draw[-o]   (c)  -- (c -| a'.west)  node [right] {c};

    end{tikzpicture}



end{document}

note: alternate voltage source hasn't polarity (as far as i know), consequently i omit signs + and -.