Demolition, site work, renovation and addition to an educational facility in Chapel Hill, North Carolina. Completed plans call for the addition of a educational facility; for the demolition of a educational facility; for the renovation of a educational facility; and for site work for a educational facility.

A. Provide Variable Frequency Drives (VFD) for each pump and fan sized to accommodate motors shown on drawings or schedules. Provide all VFDs from same manufacturer. Refer to the mechanical drawings for the VFD schedule. B. VFD manufacturer shall review driven equipment and motors for VFD compatibility. Submit written statement from manufacturer of driven equipment along with VFD shop drawing submittals, indicating verification of compatibility. C. VFD shall vary speed of its respective pump, fan or other driven equipment motor in response to either 4-20 mA control signal provided by Controls Contractor. D. VFD system shall consist of the following: 1. Variable frequency drive(s). 2. UL Listed disconnect device. 3. NEC recognized disconnect device (circuit breaker). 4. Internal reactor with minimum 5% impedance or equivalent input line reactor. 5. Operator keypad and display unit. 6. All components shall be in a common enclosure with single point wiring. 7. All auxiliary power shall be derived locally from a CPT inside the enclosure. 8. Provide internal fan(s) for cooling. E. Drives shall have SCCR (short circuit current rating) of 65 kA. F. All VFD system components, including (but not limited to) input filters, drive, output filters, harmonic filters, etc. shall be located within a common enclosure, with a single point electrical connection for supply wiring and a single point electrical connection for wiring to load (motor). Enclosure shall be properly sized and equipped with fans for cooling all components. Question Deadline 08/14/2025 at 1:00 PM ET Submit Written Questions: Direct all inquiries concerning this IFB to: Marcy Moore MRO Category Manager Email: Mmrowlan@unc.edu