US Department of Commerce/National Oceanic and Atmospheric Administration (NOAA), PGAS, Procurement Operations Division, 1325 East West Highway, Station 4301, Silver Spring, MD 20910-3283

N -- INTEGRATION AND INSTALLATION OF TRANSITION POWER MAINTENANCE SHELTERS SOL 52-DGNW-7-90004 DUE 081596 POC Robert R. Curtis, Contract Specialist, or John O. Thompson, Contracting Officer, (301) 713-0823 The Government intends to procure approximately 130 Transition Power Maintenance Shelters (TPMS), over a five year period under an indefinite quantity contract in support of National Weather Service (NWS)/Tri-Agency Doppler Weather Surveillance Radar -1988 (WSR-88D) systems. Each TPMS will be required to provide uninterrupted conditioned power to its WSR-88D system during cutover between commercial power and back-up generator power. The TPMS is a stand-alone facility consisting of the following: a precast concrete shelter, a Transition Power Source (TPS), an environmental control unit, an electric toilet unit, storage cabinets, and a workbench. The TPMS will provide limited storage and working space. A central component to be provided by the contractor is the high daily duty-cycle, long ride-through TPS that uses motor-driven technology compatible with the existing WSR-88D standby diesel generator. In addition to the concern for compatibility between the TPS and the existing generator, the NWS is concerned that necessary environmental conditions for energy storage batteries cannot be ensured and that routine servicing at remote locations cannot be guaranteed during the winter season. Notwithstanding these concerns, offerors are advised that all types of technologies will be considered for contract award. The Government intends to conduct two-step pre-award testing on the TPS, first, at the contractor's facility, and second, at the Norman, Oklahoma WSR-88D site. The WSR-88D radar system has a complex power load not commonly found in industry. The WSR-88D's existing power source is a commercial utility grade 75 KVA, 5.75% per unit impedance transformer supplying 208 Volt, 3-phase, 4-wire, 60 Hertz input power with backup power typically furnished by an emergency standby diesel generator, Kohler Model Number 80ROZJ81, rated for 80 KVA. The system load consists of WSR-88D support electronics requiring UPS protection, including a Westinghouse 750 KW peak power pulsed klystron transmitter, two 90 Amp DC servo drive motors moving an 8-ton antenna, and two 5-ton air conditioners. The air conditioners do not require TPS protection. The TPS must supply at least 35 KVA at 0.8 power factor for a continuous load of 208 +/- 5% Volts, 3-phase, 4-wire, 60 +/-5% hertz at an outdoor temperature of -40 degrees C to +49 degrees C, without derating, from mean sea level (MSL) to 3300 meters above MSL. Ride-through, the transition between commercial and back-up power, at continuous load, must be at least 12 seconds, for up to 40 transition events per day, with no degradation of voltage or frequency. The TPS must be capable of supplying overload currents of at least 600% of the continuous load for 16.7 milliseconds and 150% of the continuous load for 30 seconds, without the use of bypass mode. The voltage dip, during the transient period, caused by the application of a 0.4 power factor lagging load drawing 200% of the TPS's rated current, shall not exceed 5% of the TPS's rated voltage. The output voltage waveforms shall not exceed 3% THD at continuous load, with 50% of the load being nonlinear and no single harmonic more than 1% of fundamental frequency, from 60 hertz to 1 megahertz. The output direct-axis subtransient reactance must be 0.2 per unit, maximum and the direct-axis transient short-circuit ti (0177)

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