WyeWye 277480 4 wire Transformer Bank 2018 Iowa

Wye/Wye 277/480 4 wire Transformer Bank © 2018 Iowa Association of Electric Cooperatives DISCLAIMER: This job hazard analysis (JHA) has been made available for informational and educational purposes only. The IAEC does not make any representation or warranty with respect to the accuracy, applicability, fitness, or completeness of the JHA. The IAEC hereby disclaims any and all liability to any party for any direct, indirect, implied, punitive, special, incidental or other consequential damages arising directly or indirectly from any use of this JHA which is provided as is.

OSHA Required Tailgate Discussion Topics • Hazards Associate with the job • Work Procedures Involved • Special Precautions • Energy Source Controls • PPE Required © 2018 Iowa Association of Electric Cooperatives

Hang the required hardware Note the side that has two cutouts is opposite the system neutral. © 2018 Iowa Association of Electric Cooperatives

Parallel all of the transformers internally. Ground all of the transformer cases as well as the transformer cluster. © 2018 Iowa Association of Electric Cooperatives

Connect the primary jumpers. Leaving the high side jumpers connected to the system H 1 H 2 neutral until the entire connection is completed. © 2018 Iowa Association of Electric Cooperatives

Connect the H 2 bushings together and connect them to the system neutral and ground. You may use single bushing transformers for this connection © 2018 Iowa Association of Electric Cooperatives

Connect all X 2’s together with a jumper of equal capacity to the secondary phase wires. Connect this to the secondary neutral X 2 Neutral © 2018 Iowa Association of Electric Cooperatives

Connect the secondary phase wires to the X 1’s. X 1 Neutral Power © 2018 Iowa Association of Electric Cooperatives Power

Connect the primary jumpers and close the cutouts. X 1 Neutral Power © 2018 Iowa Association of Electric Cooperatives Power

Check the secondary voltage and rotation. X 1 Neutral Power © 2018 Iowa Association of Electric Cooperatives Power

X 1 Neutral Power © 2018 Iowa Association of Electric Cooperatives Power