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OPERATION
Before starting up or operating the fan or control panel, check all fasteners and wires for tightness. In
particular, check the blade hardware and all safety cables. With power to the fan OFF or before connecting
the fan to power, turn the fan blades by hand to be sure it is not striking any obstacles. Re-position if
necessary.
The VFDs (Variable Frequency Drives) included in this system have been factory programmed at 55Hz
(HVLS) / 80Hz (General Ventilation Fans) for high speed and 15Hz for low speed. For HVLS fans, the
speed cannot go above 55Hz. This results in a 73% reduction in airflow when operating at low speed. The
VFDs are used to adjust the speed of 3 phase motors, and frequency is directly proportional to airflow.
Exceeding the max VFD speed can cause motors to over amp and fail. Reducing speeds below the
minimum operating speed can cause motors to overheat and fail.
There are multiple ways to control fans. All methods require VFDs for 3 phase motor speed controls. Two
methods for doing this are; Smart Controls with Control logic to control the VFDs.
Smart Control Functionality
Summary of Fan Control
The purpose of the Smart Control System is to offer intelligent control of Sensible Cooling or
Destratification fans. Smart Controls offer the ability for the fans to operate AUTOMATICALLY based on
room temperature and minimum cycle timers, MANUALLY based on user input and basic scheduling
timers, by a hard wired BUILDING MANAGEMENT SYSTEM or through a DDC (Direct Digital Control)
system. Fans can be controlled individually or assigned to groups to allow one-button control of multiple
fans. All fans assigned to a group will follow that command. Also, multiple HMIs can be used to control a
single fan or multiple fans. This allows multiple HMIs to be installed in larger buildings or manager’s offices
to control the operation of fans.
Up to 10 total fans can be controlled with one control system. Fans can be arranged in groups where fan
operation is identical. There can also be a maximum of 10 HMIs assigned to a system. This allows for
flexibility on where the fans are controlled and how they are controlled. Each HMI has a built-in
temperature sensor for room sensing. In addition to this, up to 32 remote temperature sensors can be
wired into the system. They can be assigned to one or more fan groups. In total, up to 42 sensors can be
assigned to 1 or more groups (10 from HMIs, 32 from remote sensors).
Automatic Mode
In Automatic Mode, the system is designed to automatically energize fans as the room temperature rises,
modulate them based on increasing or decreasing room temperature and shut the fans down once the
room temperature falls below set-point. This mode is designed to maximize building comfort and to save
energy.
Figure 35 - Auto Mode Display
AUTO MODE
FAN 1 - GROUP 1
TEMPERATURE: 69.8°F
FAN SPEED: 53% (29Hz)
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