• Optional walk-down of the site and GSU to be held August 27th at 10:00am CT. Please contact plant engineer William Ivie wivie@ompa.com to RSVP or request a different day/time. • OMPA to de-energize and ground the high side of the transformer. OMPA to rack out and tag generation breaker and alternate feed source (low side sources). Contractor shall open L.V. terminal chamber and disconnect low side leads as needed for testing and re-attach to proper torque when complete. • Perform pre and post electrical testing to include at a minimum: o Megger core ground to 1000 volts o Winding, bushing and excitation tests o TTR o Power factor test including bushings o Arrestor watts loss • Procure and replace the remaining 2 High Side Bushings (center bushing was recently replaced) (ABB Type O 069Z0412AN or equivalent, bottom-connected) • Procure and replace 4 low side bushings. (Lapp BB1294-70 Thread 1.5-12) • Procure and replace surge arrestors on low side. (Located in L.V. terminal chamber, part # not listed on drawings) • Drain oil into a clean dry tanker. Perform a full internal inspection. Tighten blocking. Inspect and tighten all connections. Inspect DETC. Re-fill and hot vacuum process to less than 10ppm water in oil, add inhibitor (DBPC and/or DBP or approved equivalent) to at least 0.3% by total oil weight. • Replace control cabinet with a corrosion-resistant cabinet. (Please quote the following options for the control cabinet as line items) o Option 1 – Replace with a standard painted steel control cabinet o Option 2 – Replace with a stainless-steel control cabinet o Option 3 – Replace with a NEMA4X rated control cabinet • Rust treatment and painting (Please quote the following options for rust treatment and painting as line items) o Option 1 – Scrape and sand all rust and corrosion on the transformer. Treat with rust inhibitor and paint affected areas to match the transformer. o Option 2 – Remove all rust, prepare transformer for new paint, re-paint with a corrosion-resistant paint. • Replace cabinet heaters with PTC heaters, remove thermostats if equipped. • Replace PRV device and associated wiring/flex conduit. Qualitrol 208-010 01 8psi. Test alarms. • Replace rapid pressure device and associated seal in relay. (Westinghouse 8524A42G02). Test alarms. • Replace Temperature gauges and associated wiring/flex conduit. DAL-100-1 DAL-100-11. Test alarms. • Replace LLG gauge and magnetic float inside tank including any wiring/ flex conduit. Test alarms. • Replace N2 gauge on main tank including any wiring/flex conduit. Test alarms. • Add a N2 cabinet and system (SPX/Waukesha N2-1 or equivalent). Wire all N2 alarms to existing cabinet and test alarms. • Replace drain and fill valves with lockable brass ball valves with plugs installed. • Replace neutral CT. (GE JKW 6. 25kV RF=3.0 at 30C 50:5 CAT 756X50G6 SER#5566180). Test for proper operation by injecting primary current from a test set. • Regasket transformer (man holes, probe wells, bushings, etc…) • Replace fan contactors and circuit breakers. • Test all fans for proper operation in manual and auto modes. Test temperature gauge for proper operation of fan contactors. Test all alarms and wiring. • Online DGA monitor o Option 1-Install a Vaisala MHT410 with Indigo520 on drain valve. Install conduit and wiring back to the control cabinet for power and communications. o Option 2-Add a 2” drain valve (brass ball valve) at least 12” higher than the existing drain valve. Install a Vaisala MHT410 with Indigo520 on new drain valve. Install conduit and wiring back to the control cabinet for power and communications. o Option 3-Add a 2” drain valve (brass ball valve with plug installed) at least 12” higher than the existing drain valve for a future installation of a Vaisala monitor.
