In a 7200/12470 wye/delta closed bank, what voltage would you expect after the first two cutouts are closed, if the neutral was not tied down?

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In a 7200/12470 wye/delta closed bank, the voltages are based on the configurations of the transformer windings. When a wye/delta transformer bank is set up, the primary voltage (in this case, 7200 volts and 12470 volts) is distributed in accordance with the transformer's configuration.

If the neutral is not tied down, this means that the phase relationships are not referenced to a fixed potential, which can lead to unbalanced voltages being present. When the first two cutouts are closed, the transformer will operate, but the floating neutral scenario will mean that the voltage seen at the primary side will be influenced by this lack of referencing.

Given that the primary voltage in a wye system can be calculated as the line-to-line voltage divided by the square root of three, if the line-to-line voltage is close to 12470 volts, the calculated phase voltage could yield a value around 6235 volts when correctly adjusted for system configurations. Therefore, the expected voltage after closing two cutouts, without a tied-down neutral, aligns with the value of approximately 6235 volts seen on the primary side.

The other voltage values do not correspond to the primary configuration or conditions laid out in

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