Hello, I am Er. Nirav M. Madhvani Can you tell me ..How 440/230V Isolated Transformer Ratings in VA deside in Control Panels ? Means How 200 VA , 250 VA , 300 VA etc .. Select the ratings of transformer in Control Panels ???? I have attech the transformer photo shown in image file and tell me about How 440/230V Isolated Transformer Ratings in VA deside in Control Panels ?