Using the Calculator
1. Open the calculator
2. Tap “Start Here”
3. Scroll down tap “Agree”
4. On the index page Tap “Glossary”
a. The “Glossary” explains (Line Volts, Phase Volts, Line Currents and Phase Currents in Y and Delta systems)
b. The understanding of these 4 elements is a must for using the calculator accurately.
5. On the index page select the desired calculator
6. Enter the required data
a. Line volts are the phase to phase volts and will be indicated by the upper case “E”. Phase volts are the volts across the transformer winding and will be indicated by the lower case “e”.
b. Line currents are the currents on the phases and will be indicated by the upper case “I”. Phase currents are the currents across the transformer winding and will be indicated by the lower case “i”.
c. On the answer and diagram pages the primary phases are indicated with upper case letters A, B & C. The secondary phases are indicated with lower case letters a, b & c.
d. The secondary phase indications a, b & c are not a rotation sequence. They are diagram indicators. In a 4 wire delta the high leg is indicated as the c phase. When entering field derived data be sure the high leg data is entered as phase c. If both single phase and three phase loads are present on the bank the c phase will have less current than phases a & b since phase c only carries three phase current in the 4 wire delta bank. A good rule of thumb is that the current on phase c or the high leg will always be equal to or less than the current on phases a & b in the 4 wire delta connection. With both three & single phase loads present on a 4 wire delta bank you can amp phase c or the high leg to calculate the three phase load.
7. Tap “Calculate”
8. The answer page appears with a Tap button “Diagram It” For an explanation of how the calculator works scroll down the answer page.
9. Tap “Diagram It” to access the diagram and calculations.
10. On the diagram page tap the “magnifying glass” in the upper right of the diagram to expand the diagram. Once expanded to go back collapse the diagram and tap the X. This will close the diagram expansion application and allow you to go back in the calculator.
11. Tap the “Back” button on any page to return to the previous page.