BAC Custom Engineered Controls

Engineering Specifications for Equipment Controls

· Detailed Enclosed Controls Specification formatted for word processor use

· Detailed Safety Disconnect Switch Specifications formatted for word processor use

8.0 Equipment Controls (Optional)

8.1 Variable Frequency Drive(s): A variable frequency drive (VFD) shall be provided for each fan motor. The supplier of the VFD shall be the manufacturer of the evaporative cooling equipment. The VFD shall have a 3-contactor bypass, 3% input line reactor, a removable keypad, an RS232 terminal for PC connection, drive current rating of 100 kAIC, bypass rating of 36 kAIC, 500,000 hours MTBF and a circuit breaker disconnect. Fuse protection will not be accepted. Control voltage shall be 24V to minimize the size of the enclosure which should not exceed __ft x __ft x __ft and the weight of the enclosure should not exceed __lbs. VFD shall be provided in a NEMA (1) (3R) (12) enclosure. The VFD shall be compatible with a (ModBus) (LonWorks) (Johnson N2) Building Automation System.

OR

8.1 Enclosed Controls: An enclosed control panel shall be provided for each cell of the evaporative cooling equipment. The panel shall include full voltage, non-reversing (FVNR) fan motor and pump motor (if applicable) starters in a common enclosure. The panel shall use a main circuit breaker disconnect and separate circuit breakers for each motor/speed. Fuse protection will not be accepted. Panels containing basin heaters shall have an Earth Leakage Breaker containing ground fault protection. Starters above 25 A shall be NEMA rated. IEC starters will be accepted for motors 25A and below. Panel shall include a 120V/60Hz control power transformer, Hand-Off-Auto switches for each starter or contactor, and pilot lights for each component. Enclosed controls shall be provided in a NEMA (1) (3R) (4) (4X) (12) enclosure. Optional enclosed control features: (A temperature sensor shall be provided with the enclosed controls.) (A temperature controller shall be provided with the enclosed controls.) (A basin heater contactor with circuit breaker shall be provided.) (A vibration cutout switch input shall be provided.)

8.2 Safety Switch(s): A heavy-duty, non-fusible safety disconnect switch shall be provided by the manufacturer of the evaporative cooling equipment. Switch shall be single-throw, 3-pole design, rated up to 600 VAC. Switch shall have triple padlocking capability, a visible double break rotary blade mechanism, a clearly visible On/Off handle, an interlocking mechanism to prevent door from opening with handle in the On position, and a clear line shield. Safety switch shall be provided in a NEMA (1) (3R) (12) enclosure.

8.3 Universal Mounting Brackets: Mounting brackets shall be provided by the equipment manufacturer for each VFD, enclosed control panel or safety disconnect switch. The brackets will have the necessary hardware to mount the controls on the unit without penetrating the basin, handrails or platforms.