Attachment 1 - Salient Characteristics.pdf

This document is a Salient Characteristics specification for a Dual Rotary Screw Air Compressor System with Integrated Dryers configured for redundant operation.

The requirement specifies a system consisting of two identical, stand-alone, single-stage rotary screw compressors (e.g., Kaeser Model AS 25T units or equivalent) configured for redundant operation with lead-lag capability. Each compressor unit must deliver a minimum capacity of 120 cubic feet per minute (cfm) at 125 psig nominal operating/discharge pressure and be driven by a 25 horsepower motor with 208-230/460V, 3-phase, 60Hz electrical requirements. The noise level must not exceed 69 dB(A), and the system shall utilize air-cooled packages. Each compressor must feature a single-stage, fluid-injected rotary screw design with high-efficiency airend (Sigma Profile or equivalent), a Totally Enclosed Fan-Cooled (TEFC) premium-efficiency motor with Class F insulation, minimum 150% pull-up torque, automatic tensioning belt-drive system, and a Magnetic Wye-Delta reduced voltage starter in a NEMA 12-rated control panel. The integrated refrigerated air dryer must utilize R-134a refrigerant or approved equivalent, include a built-in moisture separator with automatic demand drains (Eco-Drains), and be capable of delivering a pressure dew point as low as 38°F. The air/coolant system requires a high-efficiency 1-micron intake filter with cleanable/replaceable element and an ASME-certified fluid separator tank with 3-stage separation limiting fluid carry-over to 1-3 ppm. The enclosure must be soundproofed with removable panels for maintenance access, feature a heavy-duty powder-coated finish, and include a solid steel floor base with integrated anti-vibration mounts. Each unit must have a PC-based controller (Sigma Control 2 or equivalent) with real-time operating system supporting two-unit sequencing and lead-lag operation for redundancy and balanced runtime, logging the last 100 system messages and supporting remote start/stop functionality. Safety features include an emergency stop button, ASME safety pressure relief valve, and external sight glasses for fluid levels and belt tension monitoring.