Phasor Graphs and Correct CT Connection\
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It is critical to inspect the Phasor Graphs after a Meter Installation.\
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The most commonly used meter in PNPSCADA is the Elster A1140 and the A1700\
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It is very easy to connect a Current Transformer (CT) or Voltage Transformer (VT) incorrectly on any meter.\
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There is so many reasons on site for this to happen:\

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• The cable used to connect the S1 and S2 of a CT is the same color and get mixed-up.\
  
• ​The markings on the CT's is not clear and the proper direction cannot be determined.\
  
• The S1 and S2 cable connection can be correctly connected but the P1 and P2 direction may be swapped.\
  
• The CT can be connected to the wrong Voltage Phase, this happens when using one color for all the CT connections.\
  
• The VT S1 and S2 connection to the star-point on one or both VT's can be swapped.\
  
• The VT connections on the meter can be swapped.\
  

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1. This is a good 4 wire connection as displayed in PNPSCADA.
   ​This is a typical application with some air conditioning units and Heating-elements connected.
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   For this Example We recommend swapping all the CT's S1 and S2 Polarities at the meter,\
   then changing the Red with the Blue and then after that the Blue with the White CT meter connection.
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   Note: This is only applicable if the customer do not have a captive load (Stuck Power-Factor Correction)\
   on site nor feeding reverse power to the grid.
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   For this Example We recommend swapping all the CT's S1 and S2 Polarities at the meter.\
   
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2. This is a very good example of a 3 wire connection as displayed in PNPSCADA\
   

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