connected secondary, the X2 terminals are connected to the X1 terminals on the adjacent transformers to form a “circle.” NOTE: Some utilities require a “corner grounded” secondary to reference secondary voltages to ground. Other utilities allow ungrounded delta secondary. It does not matter which phase is grounded, just ensure only one secondary phase is grounded and that any loads are grounded on the same phase. kVA Rating: The kVA rating for this type of transformer bank is three
times the individual transformer rating. Example. 3 – 25 kVA
CAUTION: Hazardous voltages exist between all ungrounded X2 transformer bushings, service conductors, the neutral, and/or ground. Exercise caution when working near these transformer bushings.
transformer will have a 75 kVA bank rating. Note: To minimize circulating currents, the three
transformers used for this service should have matching impedances as much a practical. Mismatched impedances may lead to overheating due to circulating current and pre-mature failure of the transformers.
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