All bids must strictly conform to the entire Bid Document. BIDDERS PLEASE NOTE THAT PART II, "INSTRUCTIONS TO BIDDERS," PARAGRAPH 3.3, (IB 3.3) SETS OUT THE PROCEDURE THAT BIDDERS MUST FOLLOW TO ADDRESS ANY QUESTIONS ABOUT THE REQUIREMENTS OF THIS BID DOCUMENT. The District reserves the right to reject any and all bids. Transformer shall be delivered between March 31 and May 15 of 2026, 2027 or 2028. This Specification defines a power transformer to be furnished as specified herein. These Specifications are intended to cover the design, manufacture and shop testing of one (1) threephase, 60 hertz, Ester or Mineral fluid immersed, type KNAN/KNAF/KNAF 240/320/400 MVA, outdoor power transformer, 65o C temperature rise with ester fluid or mineral oil (ALT BID) above a maximum 40o ambient, 230,000 volts wye primary to 115,000 volts wye secondary with imbedded Delta Tertiary. Tertiary configuration including MVA rating, voltage, BIL rating, and grounding to be per manufacturers recommendation. A manual external operating handle for changing taps on the primary voltage side when transformer is de-energized to be included. The high voltage winding shall have 750 kV BIL. The low voltage winding shall have a 550 kV BIL and the neutral winding shall have 150 kV BIL. Unless specified otherwise, the power transformer to be furnished shall meet all applicable requirements of ANSI C57 latest issue. Bidder may email any question(s) to accountspayable@dcpud.org, Attention: Derek Browning. DESCRIPTION OF THE ITEMS: The Work which Contractor shall perform includes: Design, manufacture, testing and delivery of 240/320/400 MVA, 230 kV to 115 kV three-phase autotransformer with load tap changer (LTC) and Delta Tertiary. Tertiary configuration including MVA rating, voltage, BIL, and grounding to be per manufacturer's recommendation. Delivery will include: o Shipping o Setting the transformer onto the pad o Coordinate clearances with the Douglas PUD o Installation of bushings, radiators and accessories o 1-hour tank tightness tees (Hold Max Vacuum, logged at 5-min intervals) o 24-hour tank Positive Pressure test (1 psi below PRD setting) o Vacuum oil (Ester fluid) filling o Delivery of the spare bushings o Frequency Response Analysis at Switchyard o Electrical Tests: Including power factor, impedance excitation, winding resistance and TTR on all taps. Final delivery point for the power transformer will be at Douglas Switchyard located at 13245 Lincoln Rock Rd, East Wenatchee, WA 98802.